ref: 79050578c7fb0a2efc4c4d9c04ba63738fb5f660
dir: /d_scan.c/
#include "quakedef.h" #include "r_fog.h" int *r_turb_turb; #include "d_scan.h" /* ============= D_WarpScreen // this performs a slight compression of the screen at the same time as // the sine warp, to keep the edges from wrapping ============= */ void D_WarpScreen (void) { static pixel_t *rowptr[MAXHEIGHT+(AMP2*2)]; static int column[MAXWIDTH+(AMP2*2)]; int w, h, u, v, *turb, *col; pixel_t *dest, **row; float wratio, hratio; w = r_refdef.vrect.width; h = r_refdef.vrect.height; wratio = w / (float)scr_vrect.width; hratio = h / (float)scr_vrect.height; for(v = 0; v < scr_vrect.height+AMP2*2; v++) rowptr[v] = dvars.fb + (r_refdef.vrect.y * dvars.w) + (dvars.w * (int)((float)v * hratio * h / (h + AMP2 * 2))); for(u = 0; u < scr_vrect.width+AMP2*2; u++) column[u] = r_refdef.vrect.x + (int)((float)u * wratio * w / (w + AMP2 * 2)); turb = intsintable + ((int)(cl.time*SPEED)&(CYCLE-1)); dest = vid.buffer + scr_vrect.y * vid.width + scr_vrect.x; for(v = 0; v < scr_vrect.height; v++, dest += vid.width){ col = &column[turb[v]]; row = &rowptr[v]; for(u = 0; u < scr_vrect.width; u += 4){ dest[u+0] = row[turb[u+0]][col[u+0]]; dest[u+1] = row[turb[u+1]][col[u+1]]; dest[u+2] = row[turb[u+2]][col[u+2]]; dest[u+3] = row[turb[u+3]][col[u+3]]; } } } static int D_DrawSpanGetMax(float u, float v) { int s, m; float us, vs; s = 4; us = u * (1<<16); vs = v * (1<<16); do{ m = 1 << (s+1); if((int)(us*m) != 0 || (int)(vs*m) != 0) return s; s++; }while(m < (int)dvars.w); return s; } void D_DrawSpans(espan_t *pspan, texvars_t *tv, byte alpha, int spanfunc) { int count, spancount, izistep, spancountminus1, spanshift, spanmax; pixel_t *pdest; uzint *pz, izi; fixed16_t s, t, snext, tnext, sstep, tstep; float sdivz, tdivz, zi, z, du, dv; float sdivzstepu, tdivzstepu, zistepu; fog_t fog; bool fogged, fogenabled; sstep = 0; // keep compiler happy tstep = 0; // ditto memset(&fog, 0, sizeof(fog)); spanshift = D_DrawSpanGetMax(tv->z.stepu, tv->z.stepv); spanmax = 1 << spanshift; sdivzstepu = tv->s.divz.stepu * spanmax; tdivzstepu = tv->t.divz.stepu * spanmax; zistepu = tv->z.stepu * spanmax; izistep = (int)(tv->z.stepu * 0x8000 * 0x10000); fogenabled = isfogged(); do{ pdest = dvars.fb + pspan->v*dvars.w + pspan->u; pz = dvars.zb + pspan->v*dvars.w + pspan->u; zi = tv->z.origin + pspan->v*tv->z.stepv + pspan->u*tv->z.stepu; izi = zi * 0x8000 * 0x10000; count = pspan->count; // calculate the initial s/z, t/z, 1/z, s, and t and clamp du = pspan->u; dv = pspan->v; sdivz = tv->s.divz.origin + dv*tv->s.divz.stepv + du*tv->s.divz.stepu; tdivz = tv->t.divz.origin + dv*tv->t.divz.stepv + du*tv->t.divz.stepu; z = (float)(1<<16) / zi; // prescale to 16.16 fixed-point s = (int)(sdivz * z) + tv->s.adjust; s = clamp(s, 0, tv->s.bbextent); t = (int)(tdivz * z) + tv->t.adjust; t = clamp(t, 0, tv->t.bbextent); do{ // calculate s and t at the far end of the span spancount = min(count, spanmax); count -= spancount; fogged = fogenabled && fogcalc(izi, izi + izistep*spancount, spancount, &fog); if(count){ // calculate s/z, t/z, zi->fixed s and t at far end of span, // calculate s and t steps across span by shifting sdivz += sdivzstepu; tdivz += tdivzstepu; // prescale to 16.16 fixed-point z = (float)(1<<16) / (zi + zistepu); snext = (int)(sdivz * z) + tv->s.adjust; // prevent round-off error on <0 steps from // causing overstepping & running off the // edge of the texture snext = clamp(snext, spanmax, tv->s.bbextent); tnext = (int)(tdivz * z) + tv->t.adjust; // guard against round-off error on <0 steps tnext = clamp(tnext, spanmax, tv->t.bbextent); sstep = (snext - s) >> spanshift; tstep = (tnext - t) >> spanshift; }else{ // calculate s/z, t/z, zi->fixed s and t at last pixel in span (so // can't step off polygon), clamp, calculate s and t steps across // span by division, biasing steps low so we don't run off the // texture spancountminus1 = spancount - 1; sdivz += tv->s.divz.stepu * spancountminus1; tdivz += tv->t.divz.stepu * spancountminus1; // prescale to 16.16 fixed-point z = (float)(1<<16) / (zi + tv->z.stepu * spancountminus1); snext = (int)(sdivz * z) + tv->s.adjust; // prevent round-off error on <0 steps from // from causing overstepping & running off the // edge of the texture snext = clamp(snext, spanmax, tv->s.bbextent); tnext = (int)(tdivz * z) + tv->t.adjust; // guard against round-off error on <0 steps tnext = clamp(tnext, spanmax, tv->t.bbextent); if(spancount > 1){ sstep = (snext - s) / spancountminus1; tstep = (tnext - t) / spancountminus1; } } pixel_t *pdest_ = pdest, *pbase = tv->p; uzint *pz_ = pz; fog_t *fog_ = &fog; int spancount_ = spancount, izi_ = izi; if(fogged){ switch(spanfunc){ case SPAN_SOLID: dospan_solid_f1(pdest_, pbase, s, t, sstep, tstep, spancount_, tv->w, pz_, izi_, izistep, fog_); break; case SPAN_TURB: dospan_turb_f1(pdest_, pbase, s, t, sstep, tstep, spancount_, alpha, pz_, izi_, izistep, fog_); break; case SPAN_BLEND: dospan_blend_f1(pdest_, pbase, s, t, sstep, tstep, spancount_, tv->w, alpha, pz_, izi_, izistep, fog_); break; case SPAN_FENCE: dospan_fence_f1(pdest_, pbase, s, t, sstep, tstep, spancount_, tv->w, pz_, izi_, izistep, fog_); break; } }else{ switch(spanfunc){ case SPAN_SOLID: dospan_solid(pdest_, pbase, s, t, sstep, tstep, spancount_, tv->w, pz_, izi_, izistep); break; case SPAN_TURB: dospan_turb(pdest_, pbase, s, t, sstep, tstep, spancount_, alpha, pz_, izi_, izistep); break; case SPAN_BLEND: dospan_blend(pdest_, pbase, s, t, sstep, tstep, spancount_, tv->w, alpha, pz_, izi_, izistep); break; case SPAN_FENCE: dospan_fence(pdest_, pbase, s, t, sstep, tstep, spancount_, tv->w, pz_, izi_, izistep); break; } } pdest += spancount; pz += spancount; izi += izistep*spancount; zi += zistepu; s = snext; t = tnext; }while(count > 0); }while((pspan = pspan->pnext) != nil); }