ref: 4175b19c94ed66fda62dddf1df57cd142963d7a9
dir: /sys/src/games/c64/vic.c/
#include <u.h> #include <libc.h> #include <thread.h> #include "dat.h" #include "fns.h" int region, picidx; u16int ppux, ppuy, lastx, wrapx, maxy, lvis, rvis, uvis, dvis, picw, pich, lbord, rbord, ubord, dbord, spr0; u16int vc, vcbase, vmli; u8int badln, rc, displ, fract, visreg, hbord, vbord, rbord0, lbord0; u16int chrp[40]; u8int pic[420*263*4*3]; u64int pxs, npxs, npxs0, opxs; u8int fg; typedef struct spr spr; enum { SPRFDMA = 1, SPRFYEX = 2, SPRFDISP = 4, }; struct spr { u8int flags; u32int data; u8int mc, mcbase, dp; u16int x; } sp[8]; void bordset(void) { int r, c; r = (reg[CTRL1] & RSEL) != 0; c = (reg[CTRL2] & CSEL) != 0; lbord = c ? 0x14 : 0x1c; lbord0 = c ? 0xf0 : 0xe0; rbord = c ? 0x154 : 0x14c; rbord0 = c ? 0x0f : 0x3f; ubord = r ? 0x33 : 0x37; dbord = r ? 0xfb : 0xf7; if((reg[CTRL1] & DEN) == 0) ubord = -1; } void vicreset(void) { switch(region){ case NTSC0: lastx = 0x1fc; wrapx = 0x19c; maxy = 262; picw = 412; pich = 234; spr0 = 0x16c; lvis = 0x1e4; rvis = 0x184; uvis = 41; dvis = 13; break; case NTSC: lastx = 0x1fc; wrapx = 0x19c; maxy = 263; picw = 419; pich = 235; spr0 = 0x174; lvis = 0x1e4; rvis = 0x18c; uvis = 41; dvis = 13; break; case PAL: lastx = 0x1f4; wrapx = 0x194; maxy = 312; picw = 404; pich = 284; spr0 = 0x164; lvis = 0x1dc; rvis = 0x17c; uvis = 16; dvis = 300; break; } ppux = 4; ppuy = 0; bordset(); } void pixeldraw(u64int p, int n) { int i, j; static u8int cr[] = {0, 255, 136, 170, 204, 0, 0, 238, 221, 102, 255, 51, 119, 170, 0, 187}; static u8int cg[] = {0, 255, 0, 255, 68, 204, 0, 238, 136, 68, 119, 51, 119, 255, 136, 187}; static u8int cb[] = {0, 255, 0, 238, 204, 85, 170, 119, 85, 0, 119, 51, 119, 102, 255, 187}; u8int *q, c; q = pic + picidx * 4 * scale; for(i = 0; i < n; i++){ c = p >> 56; p <<= 8; j = scale; do{ *q++ = cb[c]; *q++ = cg[c]; *q++ = cr[c]; q++; }while(--j); } picidx += n; } void pixels(u8int d, u16int c) { u8int c0, c1, c2, n; int i; npxs0 = npxs; npxs = 0; switch((reg[CTRL1] & (ECM|BMM) | reg[CTRL2] & MCM) >> 4){ case 0: c0 = c >> 8; normal: fg = d; for(i = 0; i < 8; i++){ npxs = npxs << 8 | ((d & 0x80) != 0 ? c0 : reg[BG0]); d <<= 1; } break; case 1: c0 = c >> 8 & 7; if((c & 0x800) == 0) goto normal; fg = d & 0xaa | d >> 1 & 0x55; for(i = 0; i < 8; i += 2){ n = d >> 6; npxs = npxs << 16 | (n == 3 ? c0 : reg[BG0 + n]) * 0x101; d <<= 2; } break; case 2: c0 = c & 15; c1 = c >> 4 & 15; fg = d; for(i = 0; i < 8; i++){ npxs = npxs << 8 | ((d & 0x80) != 0 ? c1 : c0); d <<= 1; } break; case 3: c0 = c & 15; c1 = c >> 4 & 15; c2 = c >> 8; fg = d & 0xaa | d >> 1 & 0x55; for(i = 0; i < 8; i += 2){ n = d >> 6; switch(n){ default: n = reg[BG0]; break; case 1: n = c1; break; case 2: n = c0; break; case 3: n = c2; } npxs = npxs << 16 | n * 0x101; d <<= 2; } break; case 4: c0 = c >> 8; fg = d; for(i = 0; i < 8; i++){ npxs = npxs << 8 | ((d & 0x80) != 0 ? c0 : reg[BG0 + (d >> 6 & 3)]); d <<= 1; } break; default: fg = 0; break; } } void bgpixels(void) { int i, j, x; u8int h; u8int spract, s, o; h = hbord; opxs = 0; for(i = 0; i < 8; i++){ if((reg[CTRL2] + 4 & 7) == i) pxs = i >= 4 ? npxs : npxs0; o = pxs >> 56; pxs <<= 8; x = ppux + i; spract = 0; for(j = 0; j < 8; j++) if((sp[j].flags & SPRFDISP) != 0 && (u16int)(x-sp[j].x) < 48 && (sp[j].data & ((reg[SPRMC]&1<<j)?3:2)<<22) != 0) spract |= 1<<j; if((spract & spract - 1) != 0 && vbord == 0){ reg[SPRSPR] |= spract; irq |= IRQSPRCOLL; } if(fg != 0 && spract != 0 && vbord == 0){ reg[SPRBG] |= spract; irq |= IRQBGCOLL; } s = spract & ~(reg[SPRDP] & ((s8int)fg) >> 7); if(s != 0) for(j = 0; j < 8; j++) if((s & 1<<j) != 0){ if((reg[SPRMC] & 1<<j) != 0) switch(sp[j].data >> 22 & 3){ case 1: o = reg[SPRMC0]; break; case 2: o = reg[SPRCOL+j]; break; case 3: o = reg[SPRMC1]; break; } else o = reg[SPRCOL+j]; break; } if((h & 0x80) != 0) o = reg[EC]; opxs = opxs << 8 | o; h <<= 1; fg <<= 1; for(j = 0; j < 8; j++) if((u16int)(x-sp[j].x) < 48 && ((reg[SPRXE] & 1<<j) == 0 || (x-sp[j].x & 1) != 0)) if((reg[SPRMC] & 1<<j) != 0){ if((x-sp[j].x & 1) != 0) sp[j].data <<= 2; }else sp[j].data <<= 1; } } void vicstep(void) { u16int gaddr; int i; if(ppuy == 0x30 && (reg[CTRL1] & DEN) != 0) fract = 1; badln = ((ppuy ^ reg[CTRL1]) & 7) == 0 && fract; hbord = ((s8int)(hbord << 7)) >> 7; if(ppux == rbord && hbord == 0) hbord = rbord0; else if(ppux == lbord){ if(ppuy == dbord) vbord = 1; if(ppuy == ubord) vbord = 0; if(!vbord) hbord = lbord0; } if(badln) displ = 1; if(ppux == 4){ vc = vcbase; vmli = 0; if(badln) rc = 0; } if(ppux == 12) for(i = 0; i < 8; i++){ if((sp[i].flags & SPRFDISP) == 0 || (reg[SPRYE] & 1<<i) != 0 && (sp[i].flags & SPRFYEX) == 0) continue; sp[i].mcbase += 3; if(sp[i].mcbase == 63) sp[i].flags &= ~(SPRFDMA|SPRFDISP); } if(ppux >= 0x14 && ppux <= 0x14c){ if((reg[CTRL1] & BMM) != 0) gaddr = (reg[MEMP] & 0x08) << 10 | vc << 3 | rc; else gaddr = (reg[MEMP] & 0x0e) << 10 | (chrp[vmli] & 0xff) << 3 | rc; if(!displ) gaddr = 0x3fff; if((reg[CTRL1] & ECM) != 0) gaddr &= ~0x600; pixels(vmemread(gaddr) & -displ, chrp[vmli] & -displ); vmli++; vc = vc + 1 & 0x3ff; } if(visreg && (ppux >= lvis || ppux < rvis)){ bgpixels(); pixeldraw(opxs, ppux == lvis ? region == NTSC ? 3 : 4 : 8); } if(ppux == 0x14c){ for(i = 0; i < 8; i++){ if((reg[SPRYE] & 1<<i) != 0) sp[i].flags ^= SPRFYEX; if((reg[SPREN] & 1<<i) == 0 || reg[2*i+1] != (u8int)ppuy) continue; sp[i].flags |= SPRFDMA; sp[i].mcbase = 0; if((reg[SPRYE] & 1<<i) != 0) sp[i].flags &= ~SPRFYEX; } }else if(ppux == 0x154) npxs = reg[BG0] * 0x0101010101010101ULL; if(badln){ if(ppux == lastx - 8) nrdy = 1; else if(ppux >= 0xc && ppux <= 0x144) chrp[vmli] = vmemread(vc | (reg[MEMP] & 0xf0) << 6) | cram[vc] << 8; else if(ppux == 0x154) nrdy = 0; } if(ppux == 0x164){ if(displ && rc == 7){ displ = badln; vcbase = vc; } if(displ) rc = rc + 1 & 7; for(i = 0; i < 8; i++){ sp[i].mc = sp[i].mcbase; if((sp[i].flags & SPRFDMA) != 0 && reg[2*i+1] == (u8int)ppuy) sp[i].flags |= SPRFDISP; } } if((u16int)(ppux - spr0) < 128){ i = ppux - spr0 >> 4; nrdy = (sp[i].flags & SPRFDMA) != 0; if((ppux & 8) == 0){ sp[i].dp = vmemread((reg[MEMP] & 0xf0) << 6 | 0x3f8 | i); sp[i].x = nrdy ? reg[2 * i] | reg[MSBX] << 8 - i & 0x100 : -1; if(nrdy) sp[i].data = vmemread(sp[i].dp << 6 | sp[i].mc++) << 16; }else if(nrdy){ sp[i].data = sp[i].data & 0xff00ff | vmemread(sp[i].dp << 6 | sp[i].mc++) << 8; sp[i].data = sp[i].data & 0xffff00 | vmemread(sp[i].dp << 6 | sp[i].mc++); } }else if(ppux - spr0 == 128) nrdy = 0; if(ppux == wrapx){ ppuy++; if(ppuy == maxy){ flush(); ppuy = 0; vcbase = 0; } if((ppuy & 0xff) == reg[RASTER] && ((ppuy ^ reg[CTRL1] << 1) & 0x100) == 0) irq |= IRQRASTER; if(ppuy == dbord) vbord = 1; else if(ppuy == ubord) vbord = 0; else if(ppuy == dvis) visreg = 0; if(ppuy == uvis){ picidx = 0; visreg = 1; } if(ppuy == 0xf7) fract = 0; } if(ppux == lastx) ppux = 4; else ppux += 8; }