The Graphics Engine version 1.30 Documentation
05 January 1994
The Graphics Engine software and manual are
Copyright (c) 1993-1994 by Matthew Hildebrand.
All rights reserved.
Topics covered in this document:
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INTRODUCTION
WHY USE TGE?
TERMS OF USAGE AND DISTRIBUTION
SYSTEM REQUIREMENTS
PACKING LIST
RELEASE NOTES FOR VERSION 1.30
A CRASH COURSE IN GRAPHICS PROGRAMMING
USING TGE IN A PROGRAM
TGE'S GRAPHICAL FUNCTION SET
VIEWPORTS AND CLIPPING
VIRTUAL COORDINATES
VIRTUAL SCREENS
GRAPHICAL OUTPUT MODES
USING FONTS
BITMAP MANIPULATION
PALETTE MANIPULATION
USING THE MOUSE
TGE'S MOUSE FUNCTION SET
CREATING FONTS
USING PCX2RAW AND GRAPHICS FILES
CONTACTING THE AUTHOR
OBTAINING THE NEWEST VERSION OF TGE
KNOWN PROBLEMS USING TGE
ACKNOWLEDGEMENT
LEGAL MUMBO JUMBO
INTRODUCTION
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The Graphics Engine is the result of my efforts to construct a library
of routines designed to make writing C/C++ graphics applications
easier. I have used it in my own programs with excellent results.
TGE allows the DOS programmer to easily access many graphics modes,
without having to do special coding for each; the complications
involved with supporting more than one graphics mode are removed. TGE
also provides remarkable flexibility and expandability through its
modular design.
WHY USE TGE?
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TGE provides a simple, standard interface with which programs may
access a powerful library of graphical functions. TGE supports
device-independence through the use of loadable drivers; loadable
fonts; viewports; virtual screens of definable sizes; graphics output
using COPY, AND, NOT, OR, and XOR, even to virtual screens; bitmap
scaling; interrupt-driven, definable mouse pointer services; direct
manipulation of PCX, RAW, and PAL files; and a virtual coordinate
system to make device-independence easier.
TGE's use of loadable graphics drivers means that all code and data
necessary to handle any given graphics mode is stored in a disk file.
When a program runs, this file will be loaded into memory and the code
and data it contains will be made available. Consequently:
- Support for more graphics modes may be added simply by creating
more drivers; programs need not be recompiled.
- Since the code to manage the specifics of each mode is
contained in the drivers, the main program needs not concern
itself with what mode it is operating in. The same code can
work in any graphics mode.
- Memory is saved for programs which support many graphics modes.
Instead of keeping the code and data necessary for each in
memory at all times, only the memory required for one driver is
used.
The names of the graphical functions, such as "putImage" and
"filledRect" may easily be changed to suit individual preferences.
TGE is powerful, fast, and cheap. Upgrades are free.
TERMS OF USAGE AND DISTRIBUTION
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TGE is not free; it is distributed on a "try before you buy" basis.
Permission is granted to use TGE, for evaluation purposes only, for a
trial period of up to 30 days. In order to use TGE after the trial
period, you MUST REGISTER; registration entitles you free upgrades,
technical support, a copy of TGE's source code, and royalty-free
distribution rights for all software written using TGE. Failure to
register constitutes theft and is punishable by law.
By purchasing a copy of TGE, you signify that you have read and
understood the terms of usage and distribution as laid out in this
document, and that you agree to be bound by these terms; you also
signify that you agree to release the Author (Matthew Hildebrand) from
all liability associated with the use of TGE.
In order to register a copy of TGE, send $30 US funds or $40 Canadian
funds to Matthew Hildebrand at the address listed in the CONTACTING
THE AUTHOR section of this document. Corporate users, send an
additional $100 per software package built using TGE. Payment by
money order, check, or cash is acceptable; currency must be US or
Canadian funds. Also, be sure to send a filled out copy of
REGISTER.FRM with your payment. Thank you in advance for registering
TGE; your support is what makes its continued growth possible.
Upon receipt of your registration, I will mail you a copy of the
registered version of TGE, which includes complete source code; this
copy of TGE may not be distributed in any way. Once I have mailed you
a copy of the registered version, you will be considered a registered
user. If you are interested in receiving new versions as they are
released, refer to paragraph two of the OBTAINING THE NEWEST VERSION
OF TGE section.
The privileges granted by purchasing TGE may be retracted if any of
the copyright notices in TGE's source files is modified or removed, if
any or all of the registered version of TGE is distributed in any way,
or if any or all of TGE's source code is distributed as part of a
software package.
The shareware version of TGE may be distributed freely as long as the
distributed package is complete and its contents are not modified in
any way, and the distributed package is not sold for profit.
SYSTEM REQUIREMENTS
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TGE is a C/C++ programmer's library. As such, it requires a C or C++
compiler of some sort to work with it. TGE was written and tested
with Borland C++ 2.0 and Turbo C 2.0; it should work with other C/C++
compilers as well.
The drivers that come with TGE are written using 80386 instructions;
they therefore cannot be used on a processor older than the 386 unless
they are modified first.
The font and virtual coordinate systems are written in C++, not C. In
order to use loadable fonts or VCOORD.H, a C++ compiler will be
required.
PACKING LIST
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The current version of TGE consists of the following files:
\TGE\
TGE.DOC TGE documentation.
REVISION.HST Revision history.
REGISTER.FRM Registration form (shareware version
only).
UNIVESA.DOC Universal VESA TSR documentation.
UNIVESA.EXE Universal VESA TSR executable.
README.NOW Important information.
FILE_ID.DIZ Archive description file used by some
bulletin board systems (shareware
version only).
\TGE\INCLUDE\ TGE include files.
TGE.H TGE main header file.
TGEFONT.H TGE font system header file.
TGEMOUSE.H Mouse header file.
VCOORD.H Virtual coordinate system (C++ only).
\TGE\SOURCE\ TGE's source code (registered version only).
TGE.C TGE main C file.
TGESETUP.C TGE setup file.
CLIP.C Clipping routines.
TGEFONT.CPP TGE font system (C++ only).
TGEMOUSE.ASM Various mouse routines.
MOUSEPTR.C Definable mouse pointer support.
NEWMOUSE.ASM More definable pointer support.
SCALE.C Bitmap scaling routine.
PALETTE.C Palette fading and rotation.
RAWFILE.C RAW file routines.
PCXFILE.C PCX file routines.
320X200.ASM 320x200x256 source.
320X240.ASM 320x240x256 source.
320X400.ASM 320x400x256 source.
360X480.ASM 360x480x256 source.
640X480.ASM 640x480x256 source.
800X600.ASM 800x600x256 source.
1024X768.ASM 1024x768x256 source.
SHELL.ASM Skeleton driver source; use this file
as a basis in making custom drivers.
CDRV.BAT Batch file to make a .DRV from .ASM.
\TGE\LIB\ Library directory.
BCL.MAK Makefile for Borland C++ large model
library.
BCH.MAK Makefile for Borland C++ huge model
library.
TGELIB.LST Listfile used by library makefiles.
BCL.LIB Borland C++ large model library.
BCH.LIB Borland C++ huge model library.
\TGE\UTIL\ PCX2RAW and MAKEFONT utilitites.
PCX2RAW.C Source for PCX2RAW.
PCX2RAW.EXE Convert PCX files to RAW and PAL files.
MAKEFONT.C Source for MAKEFONT.
MAKEFONT.EXE Make a font from individual bitmaps.
\TGE\DRIVERS\ Loadable drivers.
320X200.DRV Driver for VGA 320x200x256.
320X240.DRV Driver for VGA 320x240x256.
320X400.DRV Driver for VGA 320x400x256.
360X480.DRV Driver for VGA 360x480x256.
640X480.DRV Driver for SuperVGA 640x480x256.
800X600.DRV Driver for SuperVGA 800x600x256.
1024X768.DRV Driver for SuperVGA 1024x768x256.
\TGE\FONTS\ Loadable fonts.
BIGTEXT.FNT Big letters (variable-sized).
8X8.FNT 8x8 font (fixed-size).
8X14.FNT 8x14 font (fixed-size).
8X16.FNT 8x16 font (fixed-size).
\TGE\DEMO\ Demo programs.
TGEDEMO.DOC Documentation for demo program.
TGEDEMO.CPP Source code for demo program.
MAKEFILE Makefile for the demo program.
TGEDEMO.EXE TGE demo program executable.
TGELOGO.RAW Data file used by the TGE demo program.
SIMPLE.CPP A skeleton TGE program showing interface
basics.
If you did not receive all of these files, you have an illegal copy of
The Graphics Engine.
RELEASE NOTES FOR VERSION 1.30
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**IMPORTANT** Changes follow:
- TGE will no longer save and restore the palette during
text/graphics switches.
- For clarity, some of the member functions of the Font class have
been renamed; the changes are listed below, with the old names
on the left and the new names on the right. The Font class
itself has been renamed to FixedFont.
wide width
maxWide maxWidth
deep height
maxDeep maxHeight
- setBlockPalette() and getBlockPalette() now have a slightly
different argument list; refer to these functions' documentation
for details.
- MAKELIB.BAT and TGE.LIB have been replaced by BCL.LIB (Borland
C++ large model), BCL.MAK (makefile for BCL.LIB), BCH.LIB
(Borland C++ huge model), and BCH.MAK (makefile for BCH.LIB).
Rather than using MAKELIB.BAT, these libraries may now be
generated by running 'MAKE -fbcl.mak' or 'MAKE -fbch.mak'.
Now for all the nifty new stuff since 1.20:
- Added support for virtual screens of varying sizes.
- Added a virtual coordinate system to ease the task of dealing
with multiple resolutions.
- TGE can now output using COPY, AND, NOT, OR, and XOR (even to
virtual screens).
- There is now an input viewport and an output viewport, which
operate independently; ie. the input viewport is used for input
operations such as getImage(), while the output viewport is used
for output operations such as drawRect().
- The functions imageSizeDim(), putLineInv(), and vertLine() have
been added.
- There is now a bitmap scaling feature, via scaleBitmap().
- The PCX2RAW utility and the fixed-size monochrome font file
structure are now documented. (Oops...)
- TGE now supports 256-colour fonts with variable-sized characters.
The MAKEFONT utility is included to create a font file from
individual character bitmap files.
- Drivers now use 32-bit assembler code for extra speed.
- Reduced memory requirements for fixed-size monochrome fonts.
- Added support for palette fading and rotation.
- Added native support for RAW, PAL, and PCX files.
- Many optimizations, bug fixes, and documentation touch-ups.
- Added the UNIVESA TSR to the TGE package so that more SVGAs can
be supported.
- The demo program has been updated.
For a complete list of changes since TGE 1.20, refer to the
REVISION.HST file.
The drivers used with this release are not compatible with those from
version 1.20 or older, since many changes have been made to the driver
structure in order to allow for these new features.
A CRASH COURSE IN GRAPHICS PROGRAMMING
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A graphics screen is composed of thousands or even hundreds of
thousands of coloured dots called "pixels". Each pixel is referenced
according to its offset, in coordinate form, from the upper-left of
the screen: (0,0), or the "origin". The 'x' of a pixel's (x,y)
location signifies the column number, and the 'y' signifies the row
number; for example, a 640x480 screen would have (0,0) in the upper-
left and (639,479) in the lower-right.
Each of these pixels has a colour which is recorded as a number,
ranging from 0..255 in 256-colour modes. Each of these numbers is an
index into a table of colours which the video card maintains: the
"palette". The palette is what determines which colour is represented
by certain numbers; for instance, what colour is colour number 196?
Blue? Green? Purple? It depends on the current setting of the
palette register for colour number 196.
Each of these palette registers consists of three components: the
red, green, and blue values, each of which is in the range 0..255.
All the displayable colours are composed of these three primary
colours in some proportion. For instance, a purple would have lots of
red and blue, but little or no green.
The palette can be a powerful tool, as changing palette register, say,
48, causes all pixels on-screen with the value of 48 to instantly
change to the new colour. It is important to keep in mind that the
palette is a global palette; ie. it affects the entire screen.
That's all there is to it!
USING TGE IN A PROGRAM
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TGE now uses two environment variables: TGEDRIVERS and TGEFONTS.
Though these environement variables are not necessary, it is
recommended that you add the following lines to your AUTOEXEC.BAT
file:
set TGEDRIVERS=drive:\tge\drivers\
set TGEFONTS=drive:\tge\fonts\
where 'drive:' is the drive on which you installed TGE. The trailing
backslash is required.
Incorporating TGE into a program is an easy process involving three
simple steps. First, you must be sure that TGE is recognized by the
program; to do so, #include the header file TGE.H into any source file
which accesses any of TGE's routines; you may also need to #include
other header files, such as TGEMOUSE.H if you use TGE's mouse code.
Also, ensure that the appropriate library file is linked in with the
program's OBJ files to make the EXE file; available library files are
BCL.LIB (Borland C++ large model) and BCH.LIB (Borland C++ huge
model).
Second, a graphics driver MUST be loaded before any code or data
contained in the driver is accessed; results are undefined (though
almost certainly bad) if this step is not taken. Code to load a
driver might look like this:
if (loadGraphDriver(drvFileName) != TGE_SUCCESS)
{
printf("Error loading driver %s; aborting.\n\n", drvFileName);
exit(EXIT_FAILURE);
}
else
atexit(unloadGraphDriver);
The function loadGraphDriver() must be called. As its only parameter,
it takes a string consisting of the file name (which may include any
valid DOS path) of the driver to be loaded; note that if the specified
filename cannot be found, TGE will attempt to load it from the
directory specified by the TGEDRIVERS environment variable.
loadGraphDriver() returns the success code TGE_SUCCESS if the loading
was successful, or one of TGE_OPEN_ERR (file not found),
TGE_FORMAT_ERR (file is not a valid TGE driver), TGE_ALLOC_ERR (out of
memory), and TGE_FILE_ERR (general file I/O error) if an error
occurred. These macros are defined in TGE.H.
Third, after TGE's graphical functions are no longer needed (usually
just before a program exit), the function unloadGraphDriver() should
be called. It takes no parameters, and returns nothing. It simply
frees the memory taken up by a driver after it has been loaded. (With
some compilers it is not necessary to call this function, but it's
safer to call it just to be sure.) It is generally a good idea to
place unloadGraphDriver() in the atexit() queue, as was done in the
above code fragment.
Note that the initGraphics() function must be called to enter graphics
mode; for more information, see the next section. For more
information on how to use any particular feature, refer to the
appropriate section of this document.
TGE'S GRAPHICAL FUNCTION SET
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After a driver has been loaded, all of TGE's graphical functions can
be accessed. To call a function, simply execute
functionName(parameter_list);
where "functionName" is the name of the desired function (eg.
"ellipse" or "filledRect") and "parameter_list" is all parameters to
that function, if any.
A complete list of TGE's graphical functions follows.
*** Function: initGraphics()
Syntax: void initGraphics(void);
Purpose: Initialize graphics mode.
Parameters: None.
Return value: 1 on success or 0 on error.
Remarks: None.
See also: deInitGraphics()
*** Function: deInitGraphics()
Syntax: void deInitGraphics(void);
Purpose: Revert to 80x25 colour text mode.
Parameters: None.
Return value: None.
Remarks: None.
See also: initGraphics()
*** Function: putImage()
Syntax: void huge putImage(int x, int y, void far *image);
Purpose: Place a bitmap, or image, onto the screen.
Parameters: The bitmap contained in 'image' will be placed onto the
screen with its upper-left coordinate at ('x','y').
Return value: None.
Remarks: Clipping is performed; the image may be placed
entirely on-screen, partially on-screen, or entirely
off-screen.
This function is declared as huge so that it will
work properly when called from within an interrupt
service routine.
See also: putImageInv(), getImage(), imageSize(), imageSizeDim(),
putLine(), putLineInv(), getLine()
*** Function: putImageInv()
Syntax: void huge putImageInv(int x, int y, void far *image);
Purpose: Place a bitmap, or image, on the screen.
Parameters: The bitmap contained in 'image' will be placed onto the
screen with its upper-left coordinate at ('x','y').
Return value: None.
Remarks: Clipping is performed; the image may be placed
entirely on-screen, partially on-screen, or entirely
off-screen. putImageInv() differs from putImage()
only in that it allows for transparent, or invisible,
colours. If any pixel in the image buffer has a value
of zero, the corresponding pixel on-screen will not be
modified. Using putImageInv() can avoid having black
borders around non-rectangular shapes.
This function is declared as huge so that it will
work properly when called from within an interrupt
service routine.
See also: putImage(), getImage(), imageSize(), imageSizeDim(),
putLineInv(), putLine(), getLine()
*** Function: getImage()
Syntax: void huge getImage(int ulx, int uly, int lrx, int lry,
void far *image);
Purpose: Copy the specified rectangular portion of the screen to
memory.
Parameters: The portion of the screen with its upper-left
coordinate at ('ulx','uly') and its lower-left
coordinate at ('lrx','lry') will be copied into the
previously allocated memory region at 'image' (see
imageSize()).
Return value: None.
Remarks: Clipping is performed. Note that only the portion
of the specified region which lies within the current
viewport will be placed in the image buffer by
getImage(). Be careful not to assume that a getImage()
image has off-screen data in it.
This function is declared as huge so that it will
work properly when called from within an interrupt
service routine.
See also: putImage(), putImageInv(), imageSize(), imageSizeDim(),
getLine(), putLine(), putLineInv()
*** Function: imageSize()
Syntax: unsigned long imageSize(int ulx, int uly, int lrx, int
lry);
Purpose: Determine the amount of memory required to hold a
rectangular portion of the screen.
Parameters: imageSize() will calculate the amount of memory
required to hold the porion of the screen whose upper-
left coordinate is ('ulx','uly') and whose lower-left
coordinate is ('lrx','lry').
Return value: imageSize returns an unsigned long containing the size
of the area in bytes.
Remarks: Clipping is performed.
imageSize() is designed for use with putImage(),
putImageInv(), and getImage(). To use it with
putLine() and getLine(), subtract 4 from the value it
returns. (Image buffers have four bytes of dimension
information in them; line buffers do not.)
See also: imageSizeDim(), putImage(), putImageInv(), getImage(),
putLine(), getLine()
*** Function: imageSizeDim()
Syntax: unsigned long imageSizeDim(unsigned wide, unsigned
deep);
Purpose: Determine the amount of memory required to hold a
rectangular portion of the screen.
Parameters: imageSize() will calculate the amount of memory
required to hold the porion of the screen with width
'wide' and depth 'deep'.
Return value: imageSize returns an unsigned long containing the size
of the area in bytes.
Remarks: Clipping is not performed.
imageSizeDim() is designed for use with
putImage(), putImageInv(), and getImage(). To use it
with putLine() and getLine(), subtract 4 from the value
it returns. (Image buffers have four bytes of
dimension information in them; line buffers do not.)
See also: imageSize(), putImage(), putImageInv(), getImage(),
putLine(), getLine()
*** Function: putLine()
Syntax: void putLine(int lineNum, int xOff, int lineLen, void
far *buf);
Purpose: Place one horizontal line of image data on the screen.
Parameters: The one-line bitmap contained in 'buf', of 'lineLen'
pixels, will be placed on-screen starting at
('xOff','lineNum').
Return value: None.
Remarks: No clipping is performed. Results are undefined if any
coordinate on the line is off-screen.
See also: putLineInv(), getLine(), putImage(), putImageInv(),
getImage()
*** Function: putLineInv()
Syntax: void putLineInv(int lineNum, int xOff, int lineLen,
void far *buf);
Purpose: Place one horizontal line of image data on the screen,
leaving a pixel unchanged if the corresponding pixel in
the source buffer has a value of zero. This function
is the single-line equivalent to putImageInv().
Parameters: The one-line bitmap contained in 'buf', of 'lineLen'
pixels, will be placed on-screen starting at
('xOff','lineNum').
Return value: None.
Remarks: No clipping is performed. Results are undefined if any
coordinate on the line is off-screen.
See also: putLine(), getLine(), putImage(), putImageInv(),
getImage()
*** Function: getLine()
Syntax: void getLine(int lineNum, int xOff, int lineLen, void
far *buf);
Purpose: Copy one horizontal line from the screen to memory.
Parameters: The horizontal line whose left coordinate is
('xOff','lineNum') and whose length is 'lineLen' pixels
will be copied into the previously allocated memory
region at 'buf'.
Return value: None.
Remarks: No clipping is performed. Results are undefined if any
coordinate on the line is off-screen.
See also: putLine(), putLineInv(), putImage(), putImageInv(),
getImage()
*** Function: putPixel()
Syntax: void putPixel(int x, int y, unsigned colour);
Purpose: Place a single pixel on-screen.
Parameters: The pixel located at ('x','y') will be set to the
colour 'colour'.
Return value: None.
Remarks: Clipping is not performed; see clipPoint() and
pointOnScreen() for details on clipping pixels.
See also: getPixel()
*** Function: getPixel()
Syntax: unsigned getPixel(int x, int y);
Purpose: Return the value of a pixel.
Parameters: The value of the pixel at ('x','y') is returned.
Return value: The value of the pixel at ('x','y') is returned.
Remarks: Clipping is not performed; see clipPoint() and
pointOnScreen() for details on clipping pixels.
See also: putPixel()
*** Function: line()
Syntax: void line(int x1, int y1, int x2, int y2, unsigned
colour);
Purpose: Draw a line between two points.
Parameters: The line will be drawn joining ('x1','y1') and
('x2','y2') in the colour 'colour'.
Return value: None.
Remarks: Clipping is not performed; see clipLine() for details
on clipping lines.
See also: horizLine(), vertLine()
*** Function: horizLine()
Syntax: void horizLine(int y, int x1, int x2, unsigned colour);
Purpose: Draw a horizontal line between two points.
Parameters: The line will be drawn between ('x1','y') and
('x2','y') in the colour contained in colour.
Return value: None.
Remarks: Clipping is not performed.
'x1' must be less than or equal to 'x2'.
See also: vertLine(), line()
*** Function: vertLine()
Syntax: void vertLine(int x, int y1, int y2, unsigned colour);
Purpose: Draw a vertical line between two points.
Parameters: The line will be drawn between ('x','y1') and
('x','y2') in the colour contained in colour.
Return value: None.
Remarks: Clipping is not performed.
'y1' must be less than or equal to 'y2'.
See also: horizLine(), line()
*** Function: drawRect()
Syntax: void drawRect(int ulx, int uly, int lrx, int lry,
unsigned colour);
Purpose: Draw a rectangle.
Parameters: The rectangle will be drawn with its upper-left
coordinates at ('ulx','uly') and its lower-left
coordinates at ('lrx','lry'), in the colour 'colour'.
Return value: None.
Remarks: Clipping is performed.
See also: filledRect()
*** Function: filledRect()
Syntax: void filledRect(int ulx, int uly, int lrx, int lry,
unsigned colour);
Purpose: Draw a filled rectangle.
Parameters: The rectangle will be drawn with its upper-left
coordinates at ('ulx','uly') and its lower-left
coordinates at ('lrx','lry'), in the colour 'colour'.
Return value: None.
Remarks: Clipping is not performed; see clipFilledRect() for
details on clipping filledRects.
See also: drawRect()
*** Function: setPaletteReg()
Syntax: void setPaletteReg(unsigned palReg, unsigned char red,
unsigned char green, unsigned char blue);
Purpose: Set a palette register.
Parameters: The red, green, and blue components of the palette
register palReg will be set to 'red', 'green', and
'blue' respectively.
Return value: None.
Remarks: Each of the colour components ('red', 'green', 'blue')
should be in the range 0..255, not 0..63 as would be
the case using a stock VGA. The drivers will take care
of converting 8-bit to 6-bit palette resolution if
necessary.
See also: getPaletteReg(), setBlockPalette(), getBlockPalette()
*** Function: getPaletteReg()
Syntax: void getPaletteReg(unsigned palReg, unsigned char far
*red, unsigned char far *green, unsigned char far
*blue);
Purpose: Return the current settings of a palette register.
Parameters: The red, green, and blue contents of the palette
register palReg will be stored in 'red', 'green', and
'blue' respectively.
Return value: The red, green, and blue components of the palette
register are returned in 'red', 'green', and 'blue'.
Remarks: Each of the colour components ('red', 'green', 'blue')
are in the range 0..255, not 0..63 as would be the case
using a stock VGA card. The drivers will take care of
converting 8-bit to 6-bit palette resolution if
necessary.
See also: setPaletteReg(), setBlockPalette(), getBlockPalette()
*** Function: setBlockPalette()
Syntax: void setBlockPalette(unsigned firstReg, unsigned
lastReg, void far *data);
Purpose: Set a block of palette registers.
Parameters: The palette registers starting at 'firstReg' and ending
at 'lastReg' will be set to the values contained in
'data'.
Return value: None.
Remarks: The memory region at 'data' is organised in groups
of three bytes; each group corresponds to one palette
register, and each group is made up of, in order, the
red, green, and blue components. The first group is
for the first register, the second for the second, and
so on.
Each of the colour components (red, green, blue)
should be in the range 0..255, not 0..63 as would be
the case using a stock VGA. The drivers will take care
of converting 8-bit to 6-bit palette resolution if
necessary.
Results are undefined if 'lastReg' is less than
'firstReg'.
See also: getBlockPalette(), setPaletteReg(), getPaletteReg()
*** Function: getBlockPalette()
Syntax: void getBlockPalette(unsigned firstReg, unsigned
lastReg, void far *data);
Purpose: Get the values of a block of palette registers.
Parameters: The values of the palette registers starting at
'firstReg' and ending at 'lastReg' will be stored in
the previously allocated 'data'.
Return value: The values are returned in 'data'.
Remarks: The memory region at 'data' is organised in groups
of three bytes; each group corresponds to one palette
register, and each group is made up of, in order, the
red, green, and blue components. The first group is
for the first register, the second for the second, and
so on.
Each of the colour components (red, green, blue)
is in the range 0..255, not 0..63 as would be the case
using a stock VGA. The drivers will take care of
converting 8-bit to 6-bit palette resolution if
necessary.
Results are undefined if 'lastReg' is less than
'firstReg'.
See also: setBlockPalette(), setPaletteReg(), getPaletteReg()
*** Function: clearGraphics()
Syntax: void clearGraphics(unsigned colour);
Purpose: Clear the screen.
Parameters: The screen will be cleared to the colour 'colour'.
Return value: None.
Remarks: This function clears the entire screen, not just the
current viewport.
See also: filledRect()
*** Function: ellipse()
Syntax: void ellipse(int x, int y, int wide, int deep, unsigned
colour);
Purpose: Draw the outline of an ellipse.
Parameters: An ellipse centered at ('x','y') and having width
'wide' and depth 'deep' will be drawn in the colour
'colour'.
Return value: None.
Remarks: Clipping is performed.
See also: filledEllipse(), circle(), filledCircle()
*** Function: filledEllipse()
Syntax: void filledEllipse(x, int y, int wide, int deep,
unsigned colour);
Purpose: Draw a filled ellipse.
Parameters: An ellipse centered at ('x','y') and having width
'wide' and depth 'deep' will be drawn in the colour
'colour'.
Return value: None.
Remarks: Clipping is performed.
See also: ellipse(), filledCircle(), circle()
*** Function: circle()
Syntax: void circle(int x, int y, int radius, unsigned colour);
Purpose: Draw the outline of a circle.
Parameters: A circle centered at ('x','y') and having radius
'radius' will be drawn in the colour 'colour'.
Return value: None.
Remarks: Clipping is performed.
The 'radius' parameter is the radius in pixels
measured horizontally. Although there will be no
difference in modes with square pixels, it will make a
difference in other modes; to ensure accurate drawing
of the circle with the given radius, make certain that
the radius is measured horizontally.
TGE uses an all-integer approach to coordinate
scaling to ensure that the drawn shape will be circular
in modes without square pixels.
See also: filledCircle(), filledEllipse(), ellipse()
*** Function: filledCircle()
Syntax: void filledCircle(int x, int y, int radius, unsigned
colour);
Purpose: Draw a filled circle.
Parameters: A circle centered at ('x','y') and having radius
'radius' will be drawn in the colour 'colour'.
Return value: None.
Remarks: Clipping is performed.
The 'radius' parameter is the radius in pixels
measured horizontally. Although there will be no
difference in modes with square pixels, it will make a
difference in other modes; to ensure accurate drawing
of the circle with the given radius, make certain that
the radius is measured horizontally.
TGE uses an all-integer approach to coordinate
scaling to ensure that the drawn shape will be circular
in modes without square pixels.
See also: circle(), ellipse(), filledEllipse()
*** Function: fillRegion()
Syntax: void fillRegion(int x, int y, unsigned colour);
Purpose: Floods a region of the screen with the specified
colour.
Parameters: The fill will begin at the seed point ('x','y'), and
will fill with the colour 'colour'.
Return value: None.
Remarks: The region to be filled is bounded by any colour
not equal to the colour at ('x','y'); ie., the region
to be filled consists of one colour only.
Clipping is performed.
See also: None.
*** Function: colourCloseTo()
Syntax: unsigned colourCloseTo(unsigned char red, unsigned char
green, unsigned char blue);
Purpose: Given a 24-bit colour, find the colour from the current
palette which most closely matches it.
Parameters: The 24-bit colour is defined by the 'red', 'green', and
'blue' parameters.
Return value: Returns the colour which most closely matches the
specified 24-bit colour.
Remarks: None.
See also: colourCloseToX()
*** Function: colourCloseToX()
Syntax: unsigned colourCloseToX(unsigned char red, unsigned
char green, unsigned char blue, unsigned
colourExclude);
Purpose: Given a 24-bit colour, find the colour from the current
palette which most closely matches it, with the
specified colour disallowed from the search.
Parameters: The 24-bit colour is defined by the 'red', 'green', and
'blue' parameters. The colour 'colourExclude' is
excluded from the search, and so will never be
returned.
Return value: Returns the colour which most closely matches the
specified 24-bit colour.
Remarks: Excluding zero from a search will ensure that the
returned colour will be visible when it is used as part
of a bitmap displayed using putImageInv().
See also: colourCloseTo()
Note that since these function names are actually macros, they may
easily be changed to suit individual preferences by editing TGE.H.
VIEWPORTS AND CLIPPING
ßßßßßßßßßßßßßßßßßßßßßß
A viewport is a rectangular region on the screen to which output is
clipped, so that graphics output will appear only within that region.
By default, this region is the entire screen; however, it can be set
to any rectangular portion of the screen. (Note that when a viewport
is in use, coordinates are absolute, not relative to the viewport.)
TGE now supports two viewports simultaneously: an input viewport and
an output viewport. This feature was added primarily so that virtual
screens (see the VIRTUAL SCREENS section) and the real screen could be
used simultaneously, though it may have other uses as well. The
following functions are used to get and set the current input and
output viewports:
*** Function: setInputViewport()
Syntax: void setInputViewport(int ulx, int uly, int lrx, int lry);
Purpose: Set the defining coordinates of the current input
viewport.
Parameters: The upper-left corner of the input viewport will be set to
('ulx','uly'), and the lower-right corner to
('lrx','lry').
Return value: None.
Remarks: It is assumed that 'ulx'<'lrx' and that 'uly'<'lry'.
See also: setOutputViewport(), setViewport(), getInputViewport(),
getOutputViewport()
*** Function: setOutputViewport()
Syntax: void setOutputViewport(int ulx, int uly, int lrx, int lry);
Purpose: Set the defining coordinates of the current output
viewport.
Parameters: The upper-left corner of the output viewport will be set
to ('ulx','uly'), and the lower-right corner to
('lrx','lry').
Return value: None.
Remarks: It is assumed that 'ulx'<'lrx' and that 'uly'<'lry'.
See also: setInputViewport(), setViewport(), getOutputViewport(),
getInputViewport()
*** Function: setViewport()
Syntax: void setViewport(int ulx, int uly, int lrx, int lry);
Purpose: Set the defining coordinates of the current input and
output viewports.
Parameters: The upper-left corner of the viewports will be set to
('ulx','uly'), and the lower-right corner to
('lrx','lry').
Return value: None.
Remarks: It is assumed that 'ulx'<'lrx' and that 'uly'<'lry'.
See also: setInputViewport(), setOutputViewport(),
getInputViewport(), getOutputViewport()
*** Function: getInputViewport()
Syntax: void getInputViewport(int *ulx, int *uly, int *lrx, int
*lry);
Purpose: Get the defining coordinates of the current input
viewport.
Parameters: The upper-left corner of the input viewport will be stored
in ('ulx','uly'), and the lower-right corner in
('lrx','lry').
Return value: None.
Remarks: It is assumed that 'ulx'<'lrx' and that 'uly'<'lry'.
See also: getOutputViewport(), getViewport(), setInputViewport(),
setOutputViewport()
*** Function: getOutputViewport()
Syntax: void getOutputViewport(int *ulx, int *uly, int *lrx, int
*lry);
Purpose: Get the defining coordinates of the current output
viewport.
Parameters: The upper-left corner of the output viewport will be
stored in ('ulx','uly'), and the lower-right corner in
('lrx','lry').
Return value: None.
Remarks: It is assumed that 'ulx'<'lrx' and that 'uly'<'lry'.
See also: setOutputViewport(), getViewport(), getInputViewport(),
getOutputViewport()
Note that not all of TGE's functions will clip to within the current
output viewport. Some of the time-critical graphics primitives, such
as putPixel() and line(), do not clip in order to improve execution
time. If it is necessary for such functions to have their output
clipped, the following routines may be used:
*** Function: clipFilledRect()
Syntax: int clipFilledRect(int *x1, int *y1, int *x2, int *y2);
Purpose: Clip the given filled rectangle to within the current
output viewport.
Parameters: The upper-left and lower-right corners of the rectangle
are passed in ('x1','y1') and ('x2','y2'). If clipping
is done, these points will be modified.
Return value: Returns true if the rectangle lies entirely or
partially within the current output viewport, or false
if it is entirely outside the current output viewport.
Remarks: It does not matter which of the corner coordinates
is passed first; they will be swapped if necessary.
This function is contained in CLIP.C.
*** Function: clipLine()
Syntax: int clipLine(int *x1, int *y1, int *x2, int *y2);
Purpose: Clip the given line to within the current output
viewport.
Parameters: The endpoints of the line are passed in ('x1','y1') and
('x2','y2'). If clipping is done, these endpoints will
be modified.
Return value: Returns true if the line lies entirely or partially
within the current output viewport, or false if it is
entirely outside the current output viewport.
Remarks: This function is contained in CLIP.C.
See also: None.
*** Function: clipPoint()
Syntax: int clipPoint(int x, int y);
Purpose: Return a flag indicating whether or not the specified
coordinates lie within the current viewport.
Parameters: The point ('x','y') is tested.
Return value: Returns true if ('x','y') is within the current
viewport, or 0 if it isn't.
Remarks: This function is really a macro defined in TGE.H.
See also: None.
*** Function: clipInputPoint()
Syntax: int clipInputPoint(int x, int y);
Purpose: Return a flag indicating whether or not the specified
coordinates lie within the current input viewport.
Parameters: The point ('x','y') is tested.
Return value: Returns true if ('x','y') is within the current
input viewport, or 0 if it isn't.
Remarks: This function is really a macro defined in TGE.H.
See also: None.
*** Function: clipOutputPoint()
Syntax: int clipOutputPoint(int x, int y);
Purpose: Return a flag indicating whether or not the specified
coordinates lie within the current output viewport.
Parameters: The point ('x','y') is tested.
Return value: Returns true if ('x','y') is within the current
output viewport, or 0 if it isn't.
Remarks: This function is really a macro defined in TGE.H.
See also: None.
*** Function: pointOnScreen()
Syntax: int pointOnScreen(int x, int y);
Purpose: Return a flag indicating whether or not the specified
coordinates lie on-screen.
Parameters: The point ('x','y') is tested.
Return value: Returns true if ('x','y') is on-screen, or 0 if it is
off-screen.
Remarks: This function is really a macro defined in TGE.H.
See also: None.
Note that since these function names are actually macros, they may
easily be changed to suit individual preferences by editing TGE.H.
VIRTUAL COORDINATES
ßßßßßßßßßßßßßßßßßßß
One of the problems associated with device-independence is that
different display modes have different resolutions. TGE provides a
simple way to ease this problem, simply by #including VCOORD.H. Doing
so provides access to a simple yet powerful object-oriented virtual
coordinate system.
For the sake of illustration, assume that you are writing an
application which ideally will be run in resolutions as high as
1024x768, but can also be run in 320x200. You want a way to have
objects (eg., windows) retain the same sizes and positions on-screen
in any graphics mode. TGE's virtual coordinate system makes it easy.
First, create an instance of the virtual coordinate object (I'll call
the object virtScreen):
VirtualCoord virtScreen;
Then, virtScreen must be configured; I'll assume that the virtual
screen is to be 1024x768, and that OUTMAXX and OUTMAXY have been
initialized by loading a driver. (Note that these parameters may be
set during the class instantiation by using a different constructor.)
virtScreen.virtParams(1023, 767);
virtScreen.realParams(OUTMAXX, OUTMAXY);
As an example, assume that you want to draw a light gray rectangle
with upper-left coordinate (50,50) and lower-right coordinate
(600,600) on the virtual screen. On, say, a 360x480 screen these
values will be quite different; to keep the proportion the same,
execute a line like the following:
drawRect(virtScreen.realX(50), virtScreen.realY(50),
virtScreen.realX(600), virtScreen.realY(600),
colourCloseTo(200,200,200));
That's all there is to it! Keep in mind that there are other
applications of the VirtualCoord class, aside from a virtual screen;
it can also be useful when dealing with portions of the screen, scaled
bitmaps, etc..
A complete list of the VirtualCoord member functions follows.
*** Function: VirtualCoord::VirtualCoord()
Syntax: VirtualCoord::VirtualCoord(void);
Purpose: Create an instance of the VirtualCoord class.
Parameters: None.
Return value: None.
Remarks: After an instantiation of a VirtualCoord using this
constructor, ensure that the screen dimensions, both
virtual and real, are initialized using the method
illustrated above.
See also: VirtualCoord::VirtualCoord(unsigned, unsigned,
unsigned, unsigned), VirtualCoord::virtParams(unsigned,
unsigned), VirtualCoord::realParams(unsigned, unsigned)
*** Function: VirtualCoord::VirtualCoord(unsigned, unsigned,
unsigned, unsigned)
Syntax: VirtualCoord::VirtualCoord(unsigned virtMaxX, unsigned
virtMaxY, unsigned realMaxX, unsigned realMaxY);
Purpose: Create an instance of the VirtualCoord class, and
initialize it.
Parameters: The maximum virtual x-coordinate is set to 'virtMaxX',
and the y-coordinate to 'virtMaxY'. The maximum real
x-coordinate is set to 'realMaxX', and the y-coordinate
to 'realMaxY'.
Return value: None.
Remarks: Be sure that a driver has been loaded before passing
OUTMAXX and OUTMAXY to this constructor.
See also: VirtualCoord::VirtualCoord(unsigned, unsigned,
unsigned, unsigned), VirtualCoord::virtParams(unsigned,
unsigned), VirtualCoord::realParams(unsigned, unsigned)
*** Function: VirtualCoord::virtParams(unsigned, unsigned)
Syntax: void VirtualCoord::virtParams(unsigned virtMaxX,
unsigned virtMaxY);
Purpose: Set the maximum virtual x- and y-coordinates.
Parameters: The maximum virtual x-coordinate is set to 'virtMaxX',
and the maximum y-coordinate to 'virtMaxY'.
Return value: None.
Remarks: None.
See also: VirtualCoord::realParams(unsigned, unsigned),
VirtualCoord::virtParams(unsigned*, unsigned*),
VirtualCoord::realParams(unsigned*, unsigned*)
*** Function: VirtualCoord::realParams(unsigned, unsigned)
Syntax: void VirtualCoord::realParams(unsigned virtMaxX,
unsigned virtMaxY);
Purpose: Set the maximum real x- and y-coordinates.
Parameters: The maximum real x-coordinate is set to 'realMaxX', and
the maximum y-coordinate to 'realMaxY'.
Return value: None.
Remarks: None.
See also: VirtualCoord::virtParams(unsigned, unsigned),
VirtualCoord::realParams(unsigned*, unsigned*),
VirtualCoord::virtParams(unsigned*, unsigned*)
*** Function: VirtualCoord::virtParams(unsigned*, unsigned*)
Syntax: void VirtualCoord::virtParams(unsigned *virtMaxX,
unsigned *virtMaxY);
Purpose: Get the maximum virtual x- and y-coordinates.
Parameters: The maximum virtual x-coordinate is stored in
'virtMaxX', and the maximum y-coordinate in 'virtMaxY'.
Return value: None.
Remarks: None.
See also: VirtualCoord::realParams(unsigned*, unsigned*),
VirtualCoord::virtParams(unsigned, unsigned),
VirtualCoord::realParams(unsigned, unsigned)
*** Function: VirtualCoord::realParams(unsigned*, unsigned*)
Syntax: void VirtualCoord::realParams(unsigned *virtMaxX,
unsigned *virtMaxY);
Purpose: Get the maximum real x- and y-coordinates.
Parameters: The maximum real x-coordinate is stored in 'realMaxX',
and the maximum y-coordinate in 'realMaxY'.
Return value: None.
Remarks: None.
See also: VirtualCoord::virtParams(unsigned*, unsigned*),
VirtualCoord::realParams(unsigned, unsigned),
VirtualCoord::virtParams(unsigned, unsigned)
*** Function: VirtualCoord::realCoords()
Syntax: void VirtualCoord::realCoords(unsigned virtX, unsigned
virtY, unsigned *realX, unsigned *realY);
Purpose: Calculate the real (x,y) coordinates given the virtual
coordinates.
Parameters: The real (x,y) coordinates are returned in
('realX','realY'), and are calculated based on the
virtual (x,y) coordinates ('virtX','virtY').
Return value: None.
Remarks: None.
See also: VirtualCoord::realX(), VirtualCoord::realY(),
VirtualCoord::virtCoords(), VirtualCoord::virtX(),
VirtualCoord::virtY()
*** Function: VirtualCoord::realX()
Syntax: unsigned VirtualCoord::realX(unsigned virtX);
Purpose: Calculate the real x-coordinate given the virtual x-
coordinate.
Parameters: The real x-coordinate is returned, calculated based on
the virtual x-coordinate 'virtX'.
Return value: Returns the real x-coordinate.
Remarks: None.
See also: VirtualCoord::realY(), VirtualCoord::realCoords(),
VirtualCoord::virtX(), VirtualCoord::virtY(),
VirtualCoord::virtCoords()
*** Function: VirtualCoord::realY()
Syntax: unsigned VirtualCoord::realY(unsigned virtY);
Purpose: Calculate the real y-coordinate given the virtual y-
coordinate.
Parameters: The real y-coordinate is returned, calculated based on
the virtual y-coordinate 'virtY'.
Return value: Returns the real y-coordinate.
Remarks: None.
See also: VirtualCoord::realX(), VirtualCoord::realCoords(),
VirtualCoord::virtY(), VirtualCoord::virtX(),
VirtualCoord::virtCoords()
*** Function: VirtualCoord::virtCoords()
Syntax: void VirtualCoord::virtCoords(unsigned realX, unsigned
realY, unsigned *virtX, unsigned *virtY);
Purpose: Calculate the virtual (x,y) coordinates given the real
coordinates.
Parameters: The virtual (x,y) coordinates are returned in
('virtX','virtY'), and are calculated based on the real
(x,y) coordinate ('realX','realY').
Return value: None.
Remarks: None.
See also: VirtualCoord::virtX(), VirtualCoord::virtY(),
VirtualCoord::realCoords(), VirtualCoord::realX(),
VirtualCoord::realY()
*** Function: VirtualCoord::virtX()
Syntax: unsigned VirtualCoord::virtX(unsigned realX);
Purpose: Calculate the virtual x-coordinate given the real x-
coordinate.
Parameters: The virtual x-coordinate is returned, calculated based
on the real x-coordinate 'realX'.
Return value: Returns the virtual x-coordinate.
Remarks: None.
See also: VirtualCoord::virtY(), VirtualCoord::virtCoords(),
VirtualCoord::realX(), VirtualCoord::realY(),
VirtualCoord::realCoords()
*** Function: VirtualCoord::virtY()
Syntax: unsigned VirtualCoord::virtY(unsigned realY);
Purpose: Calculate the virtual y-coordinate given the real y-
coordinate.
Parameters: The virtual y-coordinate is returned, calculated based
on the real y-coordinate 'realY'.
Return value: Returns the virtual y-coordinate.
Remarks: None.
See also: VirtualCoord::virtX(), VirtualCoord::virtCoords(),
VirtualCoord::realY(), VirtualCoord::realX(),
VirtualCoord::realCoords()
VIRTUAL SCREENS
ßßßßßßßßßßßßßßß
In early releases of TGE, all graphics input and output operations
were done on the screen. Now four different I/O arrangements are
available:
- Input and output on the real screen.
- Input and output on a virtual screen (ie. in memory).
- Input from the real screen, and output to a virtual screen.
- Input from a virtual screen, and output to the real screen.
As well, it is possible to switch between these four I/O modes at any
time with one or two simple function calls.
Virtual screens are useful for such tasks as building complex images
off-screen, then displaying them quickly. Since a virtual screen has
exactly the same format as the images used by getImage() and its
associated functions, they can be displayed using a putImage() or
putImageInv() call, simply by passing the address of the virtual
screen as the address of the image to be displayed.
A virtual screen (or any bitmap, for that matter) may be created using
the following function:
*** Function: makeVirtScreen()
Syntax: void far *makeVirtScreen(unsigned wide, unsigned deep);
Purpose: Allocate enough RAM to store a virtual screen with the
specified dimensions, then initialize it.
Parameters: A virtual screen with width 'wide' and depth 'deep' (in
pixels) will be created.
Return value: Returns the address of the newly allocated virtual
screen, or NULL if there is not enough memory to create
it.
Remarks: Memory for the virtual screen is alloated from
available conventional memory; don't forget to
de-allocate (using farfree()) the memory occupied by a
virtual screen when the screen is no longer needed.
After it is allocated, a virtual screen will
likely be filled with random pixels. Clearing it using
clearGraphics() is often a good idea (after graphics
output has been set to the virtual screen).
See also: None.
The functions used to establish input and output to and from real and
virtual screens are:
*** Function: setGraphicsAddr()
Syntax: void setGraphicsAddr(void far *addr);
Purpose: Set the location upon which graphics input and output
will both be performed.
Parameters: If 'addr' is equal to NULL, input and output will be
performed on the real screen; if 'addr' is non-NULL,
input and output will be performed on the virtual
screen pointed to by 'addr'.
Return value: None.
Remarks: This function sets the currently active input and
output viewports to cover the entirety of the virtual
screen. INMAXX, INMAXY, OUTMAXX, and OUTMAXY are also
changed appropriately.
See also: setGraphicsInputAddr(), setGraphicsOutputAddr()
*** Function: setGraphicsInputAddr()
Syntax: void setGraphicsInputAddr(void far *addr);
Purpose: Set the location upon which graphics input will be
performed.
Parameters: If 'addr' is equal to NULL, input will be performed on
the real screen; if 'addr' is non-NULL, input will be
performed on the virtual screen pointed to by 'addr'.
Return value: None.
Remarks: This function sets the currently active input viewport
to cover the entirety of the virtual screen. INMAXX
and INMAXY are also changed appropriately.
See also: setGraphicsOutputAddr(), setGraphicsAddr()
*** Function: setGraphicsOutputAddr()
Syntax: void setGraphicsOutputAddr(void far *addr);
Purpose: Set the location upon which graphics output will be
performed.
Parameters: If 'addr' is equal to NULL, output will be performed on
the real screen; if 'addr' is non-NULL, output will be
performed on the virtual screen pointed to by 'addr'.
Return value: None.
Remarks: This function sets the currently active output viewport
to cover the entirety of the virtual screen. OUTMAXX
and OUTMAXY are also changed appropriately.
See also: setGraphicsInputAddr(), setGraphicsAddr()
*** Function: getGraphicsInputAddr()
Syntax: void far *getGraphicsInputAddr(void);
Purpose: Get the location upon which graphics input is currently
being performed.
Parameters: None.
Return value: Returns NULL if graphics input is currently being
performed on the physical screen, or the address of the
virtual screen upon which input is being performed
otherwise.
Remarks: None.
See also: getGraphicsOutputAddr()
*** Function: getGraphicsOutputAddr()
Syntax: void far *getGraphicsOutputAddr(void);
Purpose: Get the location upon which graphics output is currently
being performed.
Parameters: None.
Return value: Returns NULL if graphics output is currently being
performed on the physical screen, or the address of the
virtual screen upon which output is being performed
otherwise.
Remarks: None.
See also: getGraphicsInputAddr()
GRAPHICAL OUTPUT MODES
ßßßßßßßßßßßßßßßßßßßßßß
In early releases of TGE, all graphics output was copied to the
screen. Now output can be copied, ANDed, NOTed, ORed, or XORed, even
to virtual screens. A description of each of these output modes
follows:
- COPY: This mode is the one which will likely be used most
frequently. In this mode, any output is copied directly,
overwriting anything which was previously there.
- AND: In this mode, each pixel output is ANDed with the pixel
already at the same location.
- NOT: In this mode, each pixel output is NOTed before being
output.
- OR: In this mode, each pixel output is ORed with the pixel
already at the same location.
- XOR: In this mode, each pixel output is XORed with the pixel
already at the same location.
The following function allows selection of the output mode:
*** Function: setGraphicsOutputMode()
Syntax: void setGraphicsOutputMode(int mode);
Purpose: Select the currently used output mode.
Parameters: The output mode will be set to COPY if 'mode' is
TGE_COPY_PUT, AND if it is TGE_AND_PUT, NOT if it is
TGE_NOT_PUT, OR if it is TGE_OR_PUT, or XOR if it is
TGE_XOR_PUT. These macros are defined in TGE.H.
Return value: None.
Remarks: These output modes affect output to physical and
virtual screens.
See also: None.
USING FONTS
ßßßßßßßßßßß
TGE supports two types of loadable fonts: fixed-size monochrome fonts
(implemented with the FixedFont class), and variable-size 256-colour
fonts (implemented with the VariableFont class). Both high- and
low-ASCII characters are supported. As well, multiple fonts may be
resident in memory simultaneously.
For variable-size 256-colour fonts:
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
In order to use a variable-size 256-colour font, an instance of
the VariableFont class is necessary. Font initialization will
look something like this:
VariableFont systemFont;
char systemFontName[] = "BIGTEXT";
.
.
.
if (!systemFont.load(systemFontName))
{
printf("Error loading %s; aborting.\n\n", systemFontName);
exit(1);
}
Once a font has been loaded, it may be manipulated via its
VariableFont class instance. A complete list of the VariableFont
member functions follows.
*** Function: VariableFont::VariableFont()
Syntax: VariableFont::VariableFont(void);
Purpose: Initialize a VariableFont class for use with a
font before loading.
Parameters: None.
Return value: None.
Remarks: None.
See also: VariableFont::~VariableFont()
*** Function: VariableFont::~VariableFont()
Syntax: VariableFont::~VariableFont(void);
Purpose: Unload a font from memory.
Parameters: None.
Return value: None.
Remarks: None.
See also: VariableFont::VariableFont()
*** Function: VariableFont::load()
Syntax: int VariableFont::load(char *filename);
Purpose: Load a font from disk.
Parameters: The font file 'filename' will be loaded.
Return value: Returns 0 on error.
Remarks: None.
See also: None.
*** Function: VariableFont::put()
Syntax: void VariableFont::put(int x, int y, char
ch);
Purpose: Write a character on screen.
Parameters: The character 'ch' will be displayed with its
upper-left corner at ('x','y').
Return value: None.
Remarks: None.
See also: VariableFont::put(int, int, char*)
*** Function: VariableFont::put()
Syntax: void VariableFont::put(int x, int y, char
*string);
Purpose: Write a string on screen.
Parameters: The string 'string' will be displayed with its
upper-left corner at ('x','y').
Return value: None.
Remarks: None.
See also: VariableFont::put(int, int, char)
*** Function: VariableFont::width()
Syntax: unsigned VariableFont::width(char *string);
Purpose: Determine the width of a string.
Parameters: The width of the string 'string' will be
determined.
Return value: The width of the string, in pixels, will be
returned.
Remarks: None.
See also: VariableFont::width(char),
VariableFont::height(char*),
VariableFont::height(char)
*** Function: VariableFont::height()
Syntax: unsigned VariableFont::height(char *string);
Purpose: Determine the height of a string.
Parameters: The height of the string 'string' will be
determined.
Return value: The height of the string, in pixels, will be
returned.
Remarks: None.
See also: VariableFont::height(char),
VariableFont::width(char*),
VariableFont::width(char),
VariableFont::maxHeight()
*** Function: VariableFont::width()
Syntax: unsigned short VariableFont::width(char ch);
Purpose: Determine the width of a character.
Parameters: The width of the character 'ch' will be
determined.
Return value: The width of the string, in pixels, will be
returned.
Remarks: None.
See also: VariableFont::width(char*),
VariableFont::height(char),
VariableFont::width(char*)
*** Function: VariableFont::height()
Syntax: unsigned short VariableFont::height(char ch);
Purpose: Determine the height of a character.
Parameters: The height of the character 'ch' will be
determined.
Return value: The height of the string, in pixels, will be
returned.
Remarks: None.
See also: VariableFont::height(char*),
VariableFont::width(char),
VariableFont::height(char*),
VariableFont::maxHeight()
*** Function: VariableFont::maxHeight()
Syntax: unsigned short VariableFont::maxHeight(void);
Purpose: Determine the height of the tallest character.
Parameters: None.
Return value: The height of the tallest character, in pixels,
will be returned.
Remarks: None.
See also: VariableFont::height(char*),
VariableFont::height(char)
*** Function: VariableFont::matchColours()
Syntax: void VariableFont::matchColours(void);
Purpose: Match the font colours as closely as possible to
the currently selected font palette.
Parameters: None.
Return value: None.
Remarks: This function is really only useful after the
colour palette has been changed.
See also: VariableFont::palette(void*)
*** Function: VariableFont::palette(void*)
Syntax: void VariableFont::palette(void *palette);
Purpose: Change the currently active font palette.
Parameters: The currently active font palette will be set to
the palette at 'palette'.
Return value: None.
Remarks: VariableFont::matchColours() is autmatically
called by this function.
See also: VariableFont::palette(void),
VariableFont::palette(unsigned char, unsigned
char, unsigned char, unsigned char),
VariableFont::matchColours()
*** Function: VariableFont::palette(void)
Syntax: void *VariableFont::palette(void);
Purpose: Get the address of the currently active font
palette.
Parameters: None.
Return value: Returns the address of the font palette.
Remarks: If a change is made to this data directly, you
must call VariableFont::palette(void*) if the
changes are to take effect.
See also: VariableFont::palette(void),
VariableFont::palette(unsigned char, unsigned
char*, unsigned char*, unsigned char*)
*** Function: VariableFont::palette(unsigned char, unsigned
char, unsigned char, unsigned char)
Syntax: void *VariableFont::palette(unsigned char palReg,
unsigned char red, unsigned char green, unsigned
char blue);
Purpose: Change one of the colours of the font palette.
Parameters: Colour number 'palReg' of the font palette will be
set to match the values passed in 'red', 'green',
and 'blue'.
Return value: None.
Remarks: The change will take effect immediately; there is
no need to explicitly update the palette.
See also: VariableFont::palette(void*)
*** Function: VariableFont::palette(unsigned char, unsigned
char*, unsigned char*, unsigned char*)
Syntax: void *VariableFont::palette(unsigned char palReg,
unsigned char *red, unsigned char *green, unsigned
char *blue);
Purpose: Determine the contents of one of the colours of
the font palette.
Parameters: Colour number 'palReg' of the font palette will be
passed to the caller in 'red', 'green', and
'blue'.
Return value: None. On return, however, the colour's components
will be present at the 'red', 'green', and 'blue'
buffers.
Remarks: None.
See also: VariableFont::palette(void)
*** Function: VariableFont::spacing()
Syntax: void VariableFont::spacing(unsigned numPixels);
Purpose: Change the spacing between characters.
Parameters: After calling this function, the number of pixels
left between characters output with
VariableFont::put(char*) will be set to
'numPixels'.
Return value: None.
Remarks: The spacing defaults to one pixel between each
character.
See also: None.
For fixed-size monochrome fonts:
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In order to use a fixed-size monochrome font, an instance of the
FixedFont class is necessary. Assuming instantiation of a
FixedFont pointer, font initialization will look something like
this:
FixedFont *fixedFont;
char fixedFontName[] = "8X16";
.
.
.
fixedFont = new Font(fixedFontName); // load font
if (fixedFont==NULL || !fixedFont->status())
{
printf("Error loading %s; aborting.\n\n", fixedFontName);
exit(1);
}
Once a font has been loaded, it may be manipulated via its
FixedFont class instance. A complete list of the FixedFont
member functions follows.
*** Function: FixedFont::FixedFont()
Syntax: FixedFont::FixedFont(char *filename, unsigned char
fg=1, unsigned char bg=0);
Purpose: Load a font, and initiate a FixedFont class for
use with it.
Parameters: 'filename' is the name of the font data file. 'fg'
(which defaults to 1) is the colour to be used as
the foreground colour. 'bg' (which defaults to 0)
is the colour to be used as the background colour.
Return value: None.
Remarks: After an instantiation of a FixedFont, ensure that
the loading and initialization was successful
using the method illustrated above.
See also: FixedFont::~FixedFont()
*** Function: FixedFont::~FixedFont()
Syntax: FixedFont::~FixedFont()
Purpose: Free the memory used by a font, and perform any
other clean-up actions when a FixedFont is no
longer needed.
Parameters: None.
Return value: None.
Remarks: None.
See also: FixedFont::FixedFont()
*** Function: FixedFont::status()
Syntax: inline int FixedFont::status(void);
Purpose: Return a flag indicating whether or not the font
loading and initialization were successful.
Parameters: None.
Return value: Returns 1 if the initialization was successful, or
0 if it wasn't.
Remarks: None.
See also: None.
*** Function: FixedFont::width(char*)
Syntax: unsigned FixedFont::width(char *str);
Purpose: Return the width, in pixels, of a string.
Parameters: The string 'str' is analyzed.
Return value: Returns the width of 'str', in pixels.
Remarks: None.
See also: FixedFont::width(char), FixedFont::height(char*),
FixedFont::height(char), FixedFont::maxWidth(),
FixedFont::maxHeight()
*** Function: FixedFont::width(char)
Syntax: inline unsigned FixedFont::width(char ch);
Purpose: Return the width, in pixels, of a single
character.
Parameters: The character 'ch' is analyzed.
Return value: Returns the width of 'ch', in pixels.
Remarks: None.
See also: FixedFont::width(char*), FixedFont::height(char),
FixedFont::height(char*), FixedFont::maxWidth(),
FixedFont::maxHeight()
*** Function: FixedFont::maxWidth()
Syntax: inline unsigned maxWidth(void);
Purpose: Return the width of the widest character.
Parameters: None.
Return value: Returns the width of the widest character.
Remarks: None.
See also: FixedFont::maxHeight(void),
FixedFont::width(char*), FixedFont::width(char),
FixedFont::height(char*), FixedFont::height(char)
*** Function: FixedFont::height(char*)
Syntax: unsigned FixedFont::height(char *str);
Purpose: Return the height, in pixels, of a string.
Parameters: The string 'str' is analyzed.
Return value: Returns the depth of 'str', in pixels.
Remarks: None.
See also: FixedFont::height(char), FixedFont::width(char*),
FixedFont::height(char), FixedFont::maxHeight(),
FixedFont::maxWidth()
*** Function: FixedFont::height(char)
Syntax: unsigned FixedFont::height(char ch);
Purpose: Return the height, in pixels, of a single
character.
Parameters: The character 'ch' is analyzed.
Return value: Returns the height of 'ch', in pixels.
Remarks: None.
See also: FixedFont::height(char*), FixedFont::width(char),
FixedFont::width(char*), FixedFont::maxWidth(),
FixedFont::maxHeight()
*** Function: FixedFont::maxHeight()
Syntax: inline unsigned maxHeight(void);
Purpose: Return the height of the tallest character.
Parameters: None.
Return value: Returns the height of the tallest character.
Remarks: None.
See also: FixedFont::maxWidth(void),
FixedFont::height(char*), FixedFont::height(char),
FixedFont::width(char*), FixedFont::width(char)
*** Function: FixedFont::put(int, int, char*)
Syntax: void FixedFont::put(int x, int y, char *str);
Purpose: Write a string to the screen.
Parameters: The string 'str' will be written starting at
('x','y').
Return value: None.
Remarks: The coordinate passed to this function specifies
the upper-left coordinate of the string.
See also: FixedFont::put(char);
*** Function: FixedFont::put(int, int, char)
Syntax: void FixedFont::put(int x, int y, char ch);
Purpose: Write a single character to the screen.
Parameters: The character 'ch' will be written at
('x','y').
Return value: None.
Remarks: The coordinate passed to this function specifies
the upper-left coordinate of the character.
See also: FixedFont::put(char*);
*** Function: FixedFont::foreground(unsigned)
Syntax: inline void FixedFont::foreground(unsigned
colour);
Purpose: Set the current foreground colour.
Parameters: The foreground colour will be set to 'colour'.
Return value: None.
Remarks: None.
See also: FixedFont::background(unsigned),
FixedFont::foreground(void),
FixedFont::background(void)
*** Function: FixedFont::foreground(void)
Syntax: inline unsigned FixedFont::foreground(void);
Purpose: Return the current foreground colour.
Parameters: None.
Return value: Returns the current foreground colour.
Remarks: None.
See also: FixedFont::background(void),
FixedFont::foreground(unsigned),
FixedFont::foreground(unsigned)
*** Function: FixedFont::background(unsigned)
Syntax: inline void FixedFont::background(unsigned
colour);
Purpose: Set the current background colour.
Parameters: The background colour will be set to 'colour'.
Return value: None.
Remarks: None.
See also: FixedFont::foreground(unsigned),
FixedFont::background(void),
FixedFont::foreground(void)
*** Function: FixedFont::background(void)
Syntax: inline unsigned FixedFont::background(void);
Purpose: Return the current background colour.
Parameters: None.
Return value: Returns the current background colour.
Remarks: None.
See also: FixedFont::foreground(void),
FixedFont::background(unsigned),
FixedFont::foreground(unsigned)
Note that, at present, TGE's fonts are designed for use in 256-colour
modes only.
BITMAP MANIPULATION
ßßßßßßßßßßßßßßßßßßß
Bitmaps can get boring when all you can do is display them. TGE can
scale bitmaps to different sizes, using the following function:
*** Function: scaleBitmap()
Syntax: void far *scaleBitmap(void *srcImage, unsigned newWide,
unsigned newDeep, void *destImage)
Purpose: Scale the given bitmap to the specified size
Parameters: The image in 'srcImage' will be scaled to 'newWide'
pixels wide and 'newDeep' pixels deep. The resulting
scaled image will be placed in 'destImage' if
'destImage' is non-NULL, or in a newly allocated block
of memory if 'destImage' is NULL.
Return value: Returns the address of the scaled image on success, or
NULL on error. Note that NULL will never be returned
if 'destImage' is non-NULL.
Remarks: Results are undefined if either 'newWide' or 'newDeep'
is equal to zero.
See also: None.
TGE also provides routines for determining an image's dimensions given
its address:
*** Function: imageWidth
Syntax: unsigned imageWidth(void *image);
Purpose: Determine an image's width.
Parameters: This routine will determine the width of 'image'.
Return value: Returns the width, in pixels, of 'image'.
Remarks: This routine is implemented as a macro in TGE.H.
See also: imageHeight
*** Function: imageHeight
Syntax: unsigned imageHeight(void *image);
Purpose: Determine an image's height.
Parameters: This routine will determine the height of 'image'.
Return value: Returns the height, in pixels, of 'image'.
Remarks: This routine is implemented as a macro in TGE.H.
See also: imageWidth
PALETTE MANIPULATION
ßßßßßßßßßßßßßßßßßßßß
TGE provides some palette manipulation routines, described below:
*** Function: fadePalette
Syntax: int fadePalette(unsigned step, void *inPal, void
*outPal, void *targetPal);
Purpose: Fade one palette into another.
Parameters: The palette at 'inPal' will be faded closer to the
palette at 'targetPal'. The resulting palette will be
stored at 'outPal'. Each of the colour components
which compose a palette colour will be incremented or
decremented by no more than the value in 'step'; thus,
higher 'step' values produce more rapid fading.
Return value: Returns 0 if fading is complete, or 1 if it isn't.
Remarks: Note that this function does not always complete the
fading with one call. Code like this could be used:
while (fadePalette(1, in, out, target))
{
delay(10);
setBlockPalette(0, 255, out);
swap(in, out);
doSomeOtherProcessing();
}
See also: None.
*** Function: greyPalette
Syntax: void TGE_greyPalette(void *inPal, void *outPal);
Purpose: Produce a greyscale version of a palette.
Parameters: A greyscale version of the palette at 'inPal' will be
calculated, and stored at 'outPal'.
Return value: None, but the calculated greyscale palette will be at
'outPal' on return.
Remarks: Images designed with the input palette in mind will
look the same under the output greyscale palette,
except that they will be composed entirely of greys,
black, and white.
See also: None.
*** Function: rotatePalette
Syntax: void TGE_rotatePalette(int howMuch, void *inPal, void
*outPal)
Purpose: Rotate a palette.
Parameters: The palette at 'inPal' will be rotated by the value
'howMuch', and the resulting palette will be placed at
'outPal'. 'howMuch' can be negative or positive,
depending on which direction rotation will be
performed; for instance, a 'howMuch' value of 1 would
cause the value of colour 0 to move to colour 1, while
a 'howMuch' value of -1 would have the opposite effect.
Return value: None, but the rotated palette will be at 'outPal' on
return.
Remarks: This function will still operate correctly with
'howMuch' values which are greater than 255 or less
than -255.
See also: None.
USING THE MOUSE
ßßßßßßßßßßßßßßß
TGE now provides support for interrupt-driven, definable mouse
pointers. In order to make use of this feature, some simple steps
must be taken.
The new mouse handler is designed to work in tandem with TGE's
graphical functions. Programs using the new mouse handler must first
have successfully initialized graphics mode using TGE. Both TGE.H and
TGEMOUSE.H must be #included into a program using the mouse services.
The mouse handler has to be initialized. To do so, one function call
is required:
initNewMouse();
For more information on initNewMouse(), refer to the mouse functions
reference section.
Next, the mouse driver must be informed of the screen dimensions, like
this:
setHorizLimitsMouse(0, OUTMAXX);
setVertLimitsMouse(0, OUTMAXY);
If desired, the pointer may then be positioned. To center it on the
screen, do this:
setPosMouse(OUTMAXX/2, OUTMAXY/2);
A pointer shape must then be selected. TGE, as shipped, includes two
arrow pointers and two target pointers; the file MOUSEPTR.C may easily
be modified to allow more. To select, for instance, the big arrow
pointer, do this:
setupMousePointer(BIG_ARROW_POINTER);
The macro BIG_ARROW_POINTER is defined in TGEMOUSE.H; it expands to a
number which is used by MOUSEPTR.C to identify which bitmap to use.
Note that if exceptionally large (ie. larger than 512 bytes) pointers
are used, a change must be made in NEWMOUSE.ASM; see that file for
details. If you would like to directly set a bitmap as the mouse
pointer, you may use the setPointerShapeMouse() routine, described
in the next section.
Once things have been initialized, the use of the new mouse handler
over the standard mouse driver can essentially be ignored; mouse
driver services are obtained in exactly the same way. The mouse
interface functions are prototyped in TGEMOUSE.H, also using the macro
method which allows function names to be changed simply by editing
TGEMOUSE.H.
Before exiting the program, the function deInitNewMouse() _must_ be
called. It is usually a very good idea to place deInitNewMouse() in
the atexit() queue immediately after calling initNewMouse().
Note that, since the pointer is drawn using TGE's putImageInv()
function, the pointer will only appear when it is within the current
viewport.
TGE'S MOUSE FUNCTION SET
ßßßßßßßßßßßßßßßßßßßßßßßß
*** Function: initNewMouse()
Syntax: void initNewMouse(void);
Purpose: Initializes the new mouse handler.
Parameters: The new mouse handler will be configured for use with
TGE.
Return value: None.
Remarks: A graphics driver must have been loaded prior to a
call to initNewMouse().
The new mouse handler requires that a Microsoft or
compatible mouse driver already be resident. It
assumes that a mouse driver's presence will have been
tested beforehand.
initNewMouse() is really a simple macro; refer to
TGEMOUSE.H for the expansion of initNewMouse(void);
See also: deInitNewMouse(), enableNewMouse(), disableNewMouse()
*** Function: deInitNewMouse()
Syntax: void deInitNewMouse(void);
Purpose: Deactivate the new mouse handler, and leave all the
work up to the old driver.
Parameters: None.
Return value: None.
Remarks: This function must be called prior to program exit if
initNewMouse() had previously been called.
See also: initNewMouse(), enableNewMouse(), disableNewMouse()
*** Function: enableNewMouse()
Syntax: void enableNewMouse(void);
Purpose: Reactivate the new mouse handler following a call to
disableNewMouse().
Parameters: None.
Return value: None.
Remarks: None.
See also: disableNewMouse(), initNewMouse(), deInitNewMouse()
*** Function: disableNewMouse()
Syntax: void disableNewMouse(void);
Purpose: Temporarily deactivate the new mouse handler, to be
reactivated later by a call to enableNewMouse().
Parameters: None.
Return value: None.
Remarks: Following a call to this function, the new mouse
handler will cease trapping mouse driver interrupts and
moving the pointer.
See also: enableNewMouse(), initNewMouse(), deInitNewMouse()
*** Function: resetMouse()
Syntax: int resetMouse(void);
Purpose: Reset the mouse driver and hardware.
Parameters: None.
Return value: 1 if mouse driver available, 0 otherwise.
Remarks: Following a call to this function, the mouse pointer is
hidden and positioned at the center of the screen.
See also: softResetMouse(), initNewMouse()
*** Function: getButtonsMouse()
Syntax: int getButtonsMouse(void);
Purpose: Return the number of buttons on the mouse.
Parameters: None.
Return value: Returns the number of buttons on the mouse.
Remarks: This function calls resetMouse(), and so the mouse
driver and hardware are re-initialized.
See also: resetMouse()
*** Function: showMouse()
Syntax: void showMouse(void);
Purpose: Show the mouse pointer.
Parameters: None.
Return value: None.
Remarks: Calls to showMouse() and hideMouse() are cumulative;
ie., if showMouse() is called twice, hideMouse() must
be called twice to hide the pointer again.
See also: hideMouse()
*** Function: hideMouse()
Syntax: void hideMouse(void);
Purpose: Hide the mouse pointer.
Parameters: None.
Return value: None.
Remarks: Calls to showMouse() and hideMouse() are cumulative;
ie., if showMouse() is called twice, hideMouse() must
be called twice to hide the pointer again.
See also: showMouse()
*** Function: getPosMouse()
Syntax: void getPosMouse(int far *x, int far *y);
Purpose: Get the current pointer coordinates.
Parameters: The current pointer x- and y-coordinates will be stored
in 'x' and 'y', respectively.
Return value: None.
Remarks: None.
See also: setPosMouse()
*** Function: setPosMouse()
Syntax: void setPosMouse(unsigned x, unsigned y);
Purpose: Set the current pointer coordinates.
Parameters: The pointer will be positioned at ('x','y').
Return value: None.
Remarks: None.
See also: getPosMouse()
*** Function: buttonMouse()
Syntax: int buttonMouse(void);
Purpose: Return whether or not any of the mouse buttons is down.
Parameters: None.
Return value: Returns true if at least one button is down, or zero if
none of them is down.
Remarks: None.
See also: leftButtonMouse(), rightButtonMouse(),
centerButtonMouse(), waitReleaseMouse()
*** Function: leftButtonMouse()
Syntax: int leftButtonMouse(void);
Purpose: Return the status of the left mouse button.
Parameters: None.
Return value: Returns true if the button is down, or zero if it is
up.
Remarks: None.
See also: buttonMouse(), rightButtonMouse(), centerButtonMouse(),
waitReleaseMouse()
*** Function: rightButtonMouse()
Syntax: int rightButtonMouse(void);
Purpose: Return the status of the right mouse button.
Parameters: None.
Return value: Returns true if the button is down, or zero if it is
up.
Remarks: None.
See also: buttonMouse(), leftButtonMouse(), centerButtonMouse(),
waitReleaseMouse()
*** Function: centerButtonMouse()
Syntax: int centerButtonMouse(void);
Purpose: Return the status of the center mouse button.
Parameters: None.
Return value: Returns true if the button is down, or zero if it is
up.
Remarks: None.
See also: buttonMouse(), leftButtonMouse(), rightButtonMouse(),
waitReleaseMouse()
*** Function: buttonPressMouse()
Syntax: unsigned buttonPressMouse(unsigned button, int far *x,
int far *y);
Purpose: Return the number of times the specified button has
been pressed since the last call to this function (with
the same button parameter), and store the coordinates
of the last press.
Parameters: The button 'button' is checked, and may be any of
LEFTBUTTON, RIGHTBUTTON, and CENTERBUTTON, which are
defined in TGEMOUSE.H. The position of the last press
will be stored in ('x','y').
Return value: Returns the number of times the specified button has
been pressed since the last call to this function (with
the same button parameter).
Remarks: None.
See also: buttonReleaseMouse()
*** Function: buttonReleaseMouse()
Syntax: unsigned buttonReleaseMouse(unsigned button, int far
*x, int far *y);
Purpose: Return the number of times the specified button has
been released since the last call to this function
(with the same button parameter), and store the
coordinates of the last press.
Parameters: The button 'button' is checked, and may be any of
LEFTBUTTON, RIGHTBUTTON, and CENTERBUTTON, which are
defined in TGEMOUSE.H. The position of the last
release will be stored in ('x','y').
Return value: Returns the number of times the specified button has
been released since the last call to this function
(with the same button parameter).
Remarks: None.
See also: buttonPressMouse()
*** Function: setHorizLimitsMouse()
Syntax: void setHorizLimitsMouse(unsigned min, unsigned max);
Purpose: Set the minimum and maximum horizontal coordinates for
the pointer.
Parameters: The minimum horizontal coordinate will be set to 'min',
and the maximum to 'max'.
Return value: None.
Remarks: None.
See also: setVertLimitsMouse()
*** Function: setVertLimitsMouse()
Syntax: void setVertLimitsMouse(unsigned min, unsigned max);
Purpose: Set the minimum and maximum vertical coordinates for
the pointer.
Parameters: The minimum vertical coordinate will be set to 'min',
and the maximum to 'max'.
Return value: None.
Remarks: None.
See also: setHorizLimitsMouse()
*** Function: setPointerMouse()
Syntax: void setPointerMouse(int xOff, int yOff, void far *p);
Purpose: Set the shape of the pointer.
Parameters: The image pointed to by 'p' will be the pointer bitmap.
('xOff','yOff') is the offset, relative to the upper-
left corner of the bitmap, of the "hot spot" -- the
pixel where the pointer is actually registered as
being. (For instance, the standard arrow pointer has
its hot spot in the upper-left, while a crosshairs
pointer would have it towards the middle.)
Return value: None.
Remarks: The mouse pointer should be hidden when a call to this
function is made.
See also: None.
*** Function: getSaveSizeMouse()
Syntax: unsigned getSaveSizeMouse(void);
Purpose: Return the size of the buffer necessary to store the
state of the mouse driver.
Parameters: None.
Return value: Returns the size of the buffer.
Remarks: If a program using TGE and the new mouse handling
routines is to run another program, for instance
shelling to DOS, the ensuing procedure should be
followed: call disableNewMouse(), call
getSaveSizeMouse(), allocate a block of memory with the
size returned by getSaveSizeMouse(), call
saveStateMouse(), run the program, call
restoreStateMouse(), free the block of memory, then
call enableNewMouse().
See also: saveStateMouse(), restoreStateMouse()
*** Function: saveStateMouse()
Syntax: void saveStateMouse(void far *buf);
Purpose: Save the current state of the mouse driver.
Parameters: The block of memory pointed to by 'buf' will be used to
store the state data. Its length should be obtained by
calling getSaveSizeMouse().
Return value: None.
Remarks: If a program using TGE and the new mouse handling
routines is to run another program, for instance
shelling to DOS, the ensuing procedure should be
followed: call disableNewMouse(), call
getSaveSizeMouse(), allocate a block of memory with the
size returned by getSaveSizeMouse(), call
saveStateMouse(), run the program, call
restoreStateMouse(), free the block of memory, then
call enableNewMouse().
See also: getSaveSizeMouse(), restoreStateMouse()
*** Function: restoreStateMouse()
Syntax: void restoreStateMouse(void far *buf);
Purpose: Restore the state of the mouse driver from a buffer
previously filled by saveStateMouse().
Parameters: The block of memory pointed to by 'buf' stores the
state data.
Return value: None.
Remarks: If a program using TGE and the new mouse handling
routines is to run another program, for instance
shelling to DOS, the ensuing procedure should be
followed: call disableNewMouse(), call
getSaveSizeMouse(), allocate a block of memory with the
size returned by getSaveSizeMouse(), call
saveStateMouse(), run the program, call
restoreStateMouse(), free the block of memory, then
call enableNewMouse().
See also: getSaveSizeMouse, saveStateMouse
*** Function: setRatioMouse()
Syntax: void setRatioMouse(unsigned horiz, unsigned vert);
Purpose: Set the mouse sensitivity, in units of mickeys per 8
pixels of pointer movement. (A mickey is the unit used
to measure mouse movement.)
Parameters: The horizontal mickeys to pixels ratio will be set to
'horiz', and the vertical to 'vert'.
Return value: None.
Remarks: None.
See also: getSensitivityMouse()
*** Function: getSensitivityMouse()
Syntax: void getSensitivityMouse(unsigned *horiz, unsigned
*vert, unsigned *doubleSpeed);
Purpose: Get the mouse sensitivity, in units of mickeys per 8
pixels of pointer movement. (A mickey is the unit used
to measure mouse movement.) The mouse double speed
threshold (the minimum number of mickeys per second of
motion before pointer movement is doubled) is retrieved
as well.
Parameters: The horizontal mickeys to pixels ratio will be stored
in 'horiz', the vertical in 'vert', and the double
speed threshold in 'doubleSpeed'.
Return value: None.
Remarks: None.
See also: setRatioMouse()
*** Function: softResetMouse()
Syntax: void softResetMouse(void);
Purpose: Reset the mouse driver, but not the hardware.
Parameters: None.
Return value: None.
Remarks: This function is equivalent to resetMouse(), except in
that it performs no initialization of the mouse
hardware.
See also: resetMouse()
*** Function: waitReleaseMouse()
Syntax: void waitReleaseMouse(int button);
Purpose: If the specified button is not already up, wait until
it is released, then return.
Parameters: The button 'button' is checked, and may be any of
LEFTBUTTON, RIGHTBUTTON, and CENTERBUTTON, which are
defined in TGEMOUSE.H.
Return value: None.
Remarks: None.
See also: buttonMouse(), leftButtonMouse(), rightButtonMouse(),
centerButtonMouse()
Note that since these function names are actually macros, they may
easily be changed to suit individual preferences by editing
TGEMOUSE.H.
CREATING FONTS
ßßßßßßßßßßßßßß
Creating fonts is by no means easy, but the necessary information is
outlined below.
For variable-size 256-colour fonts:
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First, you should make a working directory for your font's data
files. For the sake of example, I will assume that you are
trying to create MYFONT.FNT.
Second, draw a bitmap for each of the 256 ASCII characters which
you would like to exist in the font; if you won't be using a
character, feel free to not bother drawing a bitmap for it. Each
bitmap should be as small as possible, so be sure not to leave
any extra space around the character. Use colour zero as the
background colour, or some other colour if you would like the
font to have a coloured background. Save each of these bitmaps
as a PCX file in the working directory. Note that all character
bitmaps must use the same colour palette.
Third, convert the PCX files to RAW files by using PCX2RAW; to do
so, type 'PCX2RAW *'.
Fourth, you must rename one of the PAL files produced by PCX2RAW
to MYFONT.PAL (remember MYFONT.FNT is the font you're creating).
If you wish, you may delete all the other PAL files, so long as
you leave MYFONT.PAL intact.
Fifth, you must create MYFONT.OFF, the character offset
description file. This text file consists of 256 lines, each
containing a single integer (either positive or zero), followed
by a newline. Each line contains its corresponding character's
"offset from top" value; the first line is for character 0, the
second is for character 1, and so on. Given the (x,y)
coordinates at which to put a character from the font, the
"offset from top" is the value to add to the y coordinate before
putImageInv() is called to display the character's bitmap. The
"offset from top" is used to make character bitmaps be written
lower down on the screen than other bitmaps; for instance, the
period character's offset would be greater than an asterisk's
offset, because a period is lower down than an asterisk.
Finally, you must create the font file MYFONT.FNT; to do so, type
'MAKEFONT myfont'.
For fixed-size monochrome fonts:
ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ
TGE's font definition files must have a certain format which will
be outlined below. (Note that a fixed font consists of 256
monochrome characters, each with the same dimensions.)
The font file header consists of three fields of defined length.
The first of these fields is the eight-byte font definition file
signature string, which must be "TGEFONT1", without quotes or
terminating null character. The next field is a two-byte
unsigned integer which holds the width of a character in pixels.
The last field is also a two-byte integer, holding the height of
a character in pixels.
The remainder of the file consists of font data. (If you have
done advanced text programming before, you may recognize this
data organization as the format used by the video BIOS.) The
characters are stored starting at character 0, all the way up to
255. Each of the characters is stored starting with the
uppermost row, all the way down to the bottom row. Each row is
stored left to right, with the leftmost pixel in the most
significant bit of the first byte in the row, and the rightmost
pixel in the least significant bit of the last byte in the row.
A 1 bit represents a foreground pixel, while a 0 bit represents a
background pixel. Note that, at present, font row widths must be
evenly divisible by 8; pad with 0 bits if necessary.
Image data for all 256 of the ASCII characters must be present in
the file; if you won't be needing some of them, feel free to
store zero bytes (or random bytes, if you're imaginative) as
their image data.
USING PCX2RAW AND GRAPHICS FILES
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The PCX2RAW utility provides a simple way to convert 256-colour images
in PCX format into a format usable by TGE. It is used like this:
pcx2raw filename[.pcx]
Given the PCX file FILENAME.PCX, PCX2RAW will create two new files in
the same directory as FILENAME.PCX: FILENAME.PAL which contains the
colour palette from FILENAME.PCX, and FILENAME.RAW which is a TGE
format bitmap of the image in FILENAME.PCX. Following is a discussion
of the PAL and RAW file formats, and how to use TGE's functions to
access them.
The PAL file is organized like this:
Element size Element description
------------ -------------------
3 bytes colour 0
3 bytes colour 1
.
.
.
3 bytes colour 254
3 bytes colour 255
Each 3-byte element consists of the red, green, and blue colour
components, in that order. Each of these components is an unsigned
char. Code to load a PAL file is included in RAWFILE.C; the function
description follows:
*** Function: loadPalFile()
Syntax: void far *loadPalFile(char *filename, void far *addr);
Purpose: Load a 768-byte palette file into memory.
Parameters: The palette data file 'filename' will be loaded into
the memory block at 'addr' (if 'addr' != NULL), or into
a newly allocated memory block (if 'addr' == NULL).
Return value: Returns the address of the loaded palette on success,
or NULL on error.
Remarks: If 'addr' is NULL, be sure to free() the allocated
memory block when the palette information is no longer
needed.
See also: loadPcxFilePal(), loadRawFile(), displayRawFile(),
loadPcxFile(), displayPcxFile()
The RAW file is organized in exactly the same way as the bitmaps used
by putImage() and its associated functions:
Element size Element description
------------ -------------------
2 bytes image width
2 bytes image depth
variable raw pixel information
The image dimension fields are both unsigned ints, and are measured in
pixels. Code to load a RAW file is included in RAWFILE.C; the
function descriptions follow:
*** Function: loadRawFile()
Syntax: void far *loadRawFile(char *filename);
Purpose: Load a RAW image file into memory.
Parameters: The RAW image file 'filename' will be loaded into a
newly allocated memory block.
Return value: Returns the address of the loaded image on success, or
NULL on error.
Remarks: Be sure to free() the allocated memory block when the
image information is no longer needed.
See also: displayRawFile(), loadPcxFile(), displayPcxFile(),
loadPalFile(), loadPcxFilePal()
*** Function: displayRawFile()
Syntax: int displayRawFile(int x, int y, char *filename);
Purpose: Display a RAW image file.
Parameters: The RAW image file 'filename' will be displayed with
its upper-left corner at ('x','y'). Clipping is
performed.
Return value: Returns the 1 on success, or 0 on error.
Remarks: Since this function uses standard TGE output routines,
it can display to virtual screens as well as the real
screen.
See also: loadRawFile(), displayPcxFile(), loadPcxFile(),
loadPalFile(), loadPcxFilePal()
TGE also includes routines to deal directly with PCX files:
*** Function: loadPcxFilePal()
Syntax: void far *loadPcxFilePal(char *filename, void far *addr);
Purpose: Load a 768-byte palette from a PCX file into memory.
Parameters: The palette data 'filename' will be loaded into the
memory block at 'addr' (if 'addr' != NULL), or into a
newly allocated memory block (if 'addr' == NULL).
Return value: Returns the address of the loaded palette on success,
or NULL on error.
Remarks: If 'addr' is NULL, be sure to free() the allocated
memory block when the palette information is no longer
needed.
See also: loadPalFile(), loadPcxFile(), displayPcxFile(),
loadRawFile(), displayRawFile()
*** Function: loadPcxFile()
Syntax: void far *loadPalFile(char *filename, void *palette);
Purpose: Load a PCX image file, and its palette if requested,
into memory.
Parameters: The PCX image file 'filename' will be loaded into a
newly allocated memory block. If 'palette' is
non-NULL, the 768 bytes of palette data from the PCX
file will be loaded into the memory area at 'palette'.
Return value: Returns the address of the loaded image on success, or
NULL on error. If 'palette' was non-NULL, a copy of
the palette will be at the memory area pointed to by
'palette' on return.
Remarks: Be sure to free() the allocated memory block when the
image information is no longer needed.
See also: displayPcxFile(), loadPcxFilePal(), loadRawFile(),
displayRawFile(), loadPalFile()
*** Function: displayPcxFile()
Syntax: int displayPcxFile(int x, int y, char *filename);
Purpose: Display a PCX image file.
Parameters: The PCX image file 'filename' will be displayed with
its upper-left corner at ('x','y'). Clipping is
performed.
Return value: Returns the 1 on success, or 0 on error.
Remarks: Since this function uses standard TGE output routines,
it can display to virtual screens as well as the real
screen.
See also: loadPcxFile(), displayRawFile(), loadRawFile()
CONTACTING THE AUTHOR
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I would appreciate hearing any questions, comments, bug reports, or
suggestions for improvement. If you have any, feel free to contact
me; I can be reached at any of the addresses below. When reporting
bugs, please be sure to mention the version of TGE to which you are
referring; also, if possible, please include detailed descriptions of
the problem and of your video hardware configuration. If you have a
video card which is not directly supported by TGE, I would appreciate
it if you would send me programming information about your card and/or
code to deal with it.
Snail mail: Matthew Hildebrand
4 College St.
St. Catharines, ON
Canada
L2R 2W7
Fidonet mail: 1:247/128.2
Please do not post personal messages to me in any of the
Fidonet echos, such as C_ECHO or C_PLUSPLUS; such messages
are off-topic and liable to annoy the moderator and other
echo participants. Use netmail instead. If I find any such
personal messages in Fidonet programming echos, I reply by
netmail only. If the matter being discussed is of interest
to other echo participants, I will reply in that echo.
Internet mail: Matthew.Hildebrand@p2.f128.n247.z1.fidonet.org
Internet-Fidonet mail routing sometimes goes awry; if you
don't get a reply from me after a reasonable amount of time,
send the message again. If you still don't receive a reply,
either persist until you do or contact me via snail mail or
Fidonet mail.
OBTAINING THE NEWEST VERSION OF TGE
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The most recent distributed copy of TGE is available via first-call
download from (905)-935-6628 (14400 bps V.32bis), or via file request
from Fidonet node 1:247/128 (14400 bps V.32bis) using the magic file
name "TGE"; unlisted nodes and points are welcome. TGE is also
distributed through the Fidonet file echo PDNCEE.
If, after you have registered, you are interested in receiving new
versions of TGE as they are released, an easy method is now available.
For $3 per mailing (to cover the disk, envelope, and postage), I will
mail copies of new versions as they are released, on either a 3.5" or
a 5.25" disk. The $3 per mailing may be included with the initial
registration fee, with instructions to mail newer versions as they are
released, or mailed later with a request for a copy of the newest
version. Please ensure that the $3 is paid in either US or Canadian
funds; payment by check, cash, or money order is acceptable.
KNOWN PROBLEMS USING TGE
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At present, the following problems may be experienced when using TGE:
1. (Registered users only.) When TGE.C is compiled by Turbo
C++ 3.0, putImage() and putImageInv() do not work correctly.
When informed of this bug, I stepped through the offending
code at the assembly level, and discovered that this problem
is caused by a bug in TC++, not TGE. The miscompiled lines
of TGE.C are perfectly legal C statements; when TGE.C is
compiled by my compiler (Borland C++ 2.0), TGE works
beautifully. Using one of the TGE library files included in
the TGE package, rather than OBJ files compiled by Turbo C++
3.0, should solve the problem.
2. A very small number of users may experience an odd pattern
of blue lines when TGE is run in an SVGA mode on some older
ATI cards. I have been informed that this problem is caused
by a bug in the video card itself. ATI has confirmed the
presence of this bug, and has implemented a software patch
in its Windows 3.1 SVGA driver, but ATI has not released
information on how this bug was squashed.
ACKNOWLEDGEMENT
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There are many people whom I would like to thank for their
suggestions, beta-testing, patience, registrations, and help with
distribution. You know who you are.
LEGAL MUMBO JUMBO
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The Graphics Engine and its documentation are Copyright (c) 1993-1994
by Matthew Hildebrand.
All software and documentation associated with The Graphics Engine is
provided "as is": ie., it is provided without warranty of any kind,
not even an implied warranty of merchantability or fitness for any
purpose. The Author (Matthew Hildebrand) disclaims all warranties,
both express and implied, including but not limited to warranties
regarding The Graphics Engine's merchantability or fitness for any
particular purpose.
The author may not be held liable for any damage or misfortune related
to the use of this software. The usage of any or all of The Graphics
Engine is done entirely at the user's risk.
All registered trademarks in this document belong to whomever it is
that owns them.
End of document.