29 lines
715 B
C
29 lines
715 B
C
/* VGA mode 13h pixel-drawing and mode set functions.
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* Tested with Borland C++ in C compilation mode and the small model.
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*/
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#include <dos.h>
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/* Screen dimension globals, used in main program to scale. */
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int ScreenWidthInPixels = 320;
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int ScreenHeightInPixels = 200;
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/* Mode 13h draw pixel function. */
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void DrawPixel(int X, int Y, int Color)
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{
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#define SCREEN_SEGMENT 0xA000
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unsigned char far *ScreenPtr;
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FP_SEG(ScreenPtr) = SCREEN_SEGMENT;
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FP_OFF(ScreenPtr) = (unsigned int) Y * ScreenWidthInPixels + X;
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*ScreenPtr = Color;
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}
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/* Mode 13h mode-set function. */
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void SetMode()
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{
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union REGS regset;
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/* Set to 320x200 256-color graphics mode */
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regset.x.ax = 0x0013;
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int86(0x10, ®set, ®set);
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}
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