32 lines
603 B
C
32 lines
603 B
C
#include <string.h>
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typedef unsigned char byte;
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typedef signed char sbyte;
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typedef unsigned short word;
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byte __at (0x2400) vidmem[224][32]; // 256x224x1 video memory
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void clrscr() {
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memset(vidmem, 0, sizeof(vidmem));
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}
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void xor_pixel(byte x, byte y) {
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byte* dest = &vidmem[x][y>>3];
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*dest ^= 0x1 << (y&7);
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}
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byte xor_sprite(const byte* src, byte x, byte y) {
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byte i,j;
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byte result = 0;
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byte* dest = &vidmem[x][y];
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byte w = *src++;
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byte h = *src++;
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for (j=0; j<h; j++) {
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for (i=0; i<w; i++) {
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result |= (*dest++ ^= *src++);
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}
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dest += 32-w;
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}
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return result;
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}
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