ref: fe5d1976a0b4376c955ca8423eb9005f5d035403
dir: /sys/src/games/2600/tia.c/
#include <u.h> #include <libc.h> #include "../eui.h" #include "dat.h" #include "fns.h" int ppux=1, ppuy; int col, pri; u8int p0x, p1x, m0x, m1x, blx; u16int coll; u8int disp; int p0difc; int bwmod = 1<<3; enum { SRCPF, SRCP0, SRCP1, SRCM0, SRCM1, SRCBL, }; static void pixeldraw(u8int v) { u32int c; union { u32int l; u8int c[4]; } u; u32int *p; static u32int col[] = { 0x000000, 0x404040, 0x6C6C6C, 0x909090, 0xB0B0B0, 0xC8C8C8, 0xDCDCDC, 0xECECEC, 0x444400, 0x646410, 0x848424, 0xA0A034, 0xB8B840, 0xD0D050, 0xE8E85C, 0xFCFC68, 0x702800, 0x844414, 0x985C28, 0xAC783C, 0xBC8C4C, 0xCCA05C, 0xDCB468, 0xECC878, 0x841800, 0x983418, 0xAC5030, 0xC06848, 0xD0805C, 0xE09470, 0xECA880, 0xFCBC94, 0x880000, 0x9C2020, 0xB03C3C, 0xC05858, 0xD07070, 0xE08888, 0xECA0A0, 0xFCB4B4, 0x78005C, 0x8C2074, 0xA03C88, 0xB0589C, 0xC070B0, 0xD084C0, 0xDC9CD0, 0xECB0E0, 0x480078, 0x602090, 0x783CA4, 0x8C58B8, 0xA070CC, 0xB484DC, 0xC49CEC, 0xD4B0FC, 0x140084, 0x302098, 0x4C3CAC, 0x6858C0, 0x7C70D0, 0x9488E0, 0xA8A0EC, 0xBCB4FC, 0x000088, 0x1C209C, 0x3840B0, 0x505CC0, 0x6874D0, 0x7C8CE0, 0x90A4EC, 0xA4B8FC, 0x00187C, 0x1C3890, 0x3854A8, 0x5070BC, 0x6888CC, 0x7C9CDC, 0x90B4EC, 0xA4C8FC, 0x002C5C, 0x1C4C78, 0x386890, 0x5084AC, 0x689CC0, 0x7CB4D4, 0x90CCE8, 0xA4E0FC, 0x003C2C, 0x1C5C48, 0x387C64, 0x509C80, 0x68B494, 0x7CD0AC, 0x90E4C0, 0xA4FCD4, 0x003C00, 0x205C20, 0x407C40, 0x5C9C5C, 0x74B474, 0x8CD08C, 0xA4E4A4, 0xB8FCB8, 0x143800, 0x345C1C, 0x507C38, 0x6C9850, 0x84B468, 0x9CCC7C, 0xB4E490, 0xC8FCA4, 0x2C3000, 0x4C501C, 0x687034, 0x848C4C, 0x9CA864, 0xB4C078, 0xCCD488, 0xE0EC9C, 0x442800, 0x644818, 0x846830, 0xA08444, 0xB89C58, 0xD0B46C, 0xE8CC7C, 0xFCE08C, }; c = col[v >> 1]; u.c[0] = c; u.c[1] = c >> 8; u.c[2] = c >> 16; u.c[3] = 0xff; p = (u32int *)pic + ppuy * PICW * scale + ppux * 2 * scale; switch(scale){ case 16: *p++ = u.l; *p++ = u.l; case 15: *p++ = u.l; *p++ = u.l; case 14: *p++ = u.l; *p++ = u.l; case 13: *p++ = u.l; *p++ = u.l; case 12: *p++ = u.l; *p++ = u.l; case 11: *p++ = u.l; *p++ = u.l; case 10: *p++ = u.l; *p++ = u.l; case 9: *p++ = u.l; *p++ = u.l; case 8: *p++ = u.l; *p++ = u.l; case 7: *p++ = u.l; *p++ = u.l; case 6: *p++ = u.l; *p++ = u.l; case 5: *p++ = u.l; *p++ = u.l; case 4: *p++ = u.l; *p++ = u.l; case 3: *p++ = u.l; *p++ = u.l; case 2: *p++ = u.l; *p++ = u.l; default: *p++ = u.l; *p = u.l; } } static void pixel(u8int v, int p, int s) { if(p > pri){ col = v; pri = p; } disp |= 1<<s; } static void playfield(void) { int x, p; u8int c; x = ppux / 4; if(x >= 20) if((reg[CTRLPF] & 1) != 0) x = 39 - x; else x = x - 20; if(x < 4){ if((reg[PF0] & 0x10<<x) == 0) return; }else if(x < 12){ if((reg[PF1] & 0x800>>x) == 0) return; }else if((reg[PF2] & 1<<x-12) == 0) return; if((reg[CTRLPF] & 6) == 2) if(ppux < 80){ c = reg[COLUP0]; p = 3; }else{ c = reg[COLUP1]; p = 2; } else{ c = reg[COLUPF]; p = (reg[CTRLPF] & 4) + 1; } pixel(c, p, SRCPF); } static void player(int n) { u8int c; int x; c = reg[GRP0 + n]; x = ppux - (n ? p1x : p0x); if(x < 0) return; switch(reg[NUSIZ0 + n] & 7){ default: if(x >= 8) return; break; case 1: if(x >= 8 && (x < 16 || x >= 24)) return; break; case 2: if(x >= 8 && (x < 32 || x >= 40)) return; break; case 3: if(x >= 40 || ((x & 15) >= 8)) return; break; case 4: if(x >= 8 && (x < 64 || x >= 72)) return; break; case 5: if(x >= 16) return; x >>= 1; break; case 6: if(x >= 72 || ((x & 31) >= 8)) return; break; case 7: if(x >= 32) return; x >>= 2; break; } x &= 7; if((reg[REFP0 + n] & 8) == 0) x ^= 7; if((c & 1<<x) == 0) return; c = reg[COLUP0 + n]; pixel(c, 3 - n, SRCP0 + n); } static void missile(int n) { int x; x = ppux - (n ? m1x : m0x); if((reg[RESMP0 + n] & 2) != 0){ if(n) m1x = p1x; else m0x = p0x; return; } if(x < 0 || x >= 1<<(reg[NUSIZ0] >> 4 & 3) || (reg[ENAM0 + n] & 2) == 0) return; pixel(reg[COLUP0 + n], 3 - n, SRCM0 + n); } static void ball(void) { int x; x = ppux - blx; if(x < 0 || x >= 1<<(reg[CTRLPF] >> 4 & 3) || (reg[ENABL] & 2) == 0) return; pixel(reg[COLUPF], (reg[CTRLPF] & 4) + 1, SRCBL); } void tiastep(void) { static u16int colltab[64] = { 0x0000, 0x0000, 0x0000, 0x0020, 0x0000, 0x0080, 0x8000, 0x80a0, 0x0000, 0x0200, 0x0001, 0x0221, 0x0002, 0x0282, 0x8003, 0x82a3, 0x0000, 0x0800, 0x0008, 0x0828, 0x0004, 0x0884, 0x800c, 0x88ac, 0x4000, 0x4a00, 0x4009, 0x4a29, 0x4006, 0x4a86, 0xc00f, 0xcaaf, 0x0000, 0x2000, 0x0010, 0x2030, 0x0040, 0x20c0, 0x8050, 0xa0f0, 0x0100, 0x2300, 0x0111, 0x2331, 0x0142, 0x23c2, 0x8153, 0xa3f3, 0x0400, 0x2c00, 0x0418, 0x2c38, 0x0444, 0x2cc4, 0x845c, 0xacfc, 0x4500, 0x6f00, 0x4519, 0x6f39, 0x4546, 0x6fc6, 0xc55f, 0xefff, }; if(ppuy < PICH && ppux < 160){ col = reg[COLUBK]; pri = 0; disp = 0; playfield(); player(0); player(1); missile(0); missile(1); ball(); coll |= colltab[disp]; pixeldraw(col); } if(ppux == 160) nrdy = 0; if(++ppux == 228){ ppuy++; ppux = 0; } }