ref: 3a83bca01f54db3fdbde78658787664968b04aab
dir: /d_scan.c/
#include "quakedef.h"
#include "r_fog.h"
int *r_turb_turb;
/*
=============
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.viewbuffer + (r_refdef.vrect.y * dvars.width) + (dvars.width * (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 inline void
dospan_solid(pixel_t *pdest, pixel_t *pbase, int s, int t, int sstep, int tstep, int spancount, int width, uzint *pz, uzint izi, int izistep)
{
pixel_t pix;
do{
*pz++ = izi;
pix = pbase[(s >> 16) + (t >> 16) * width];
s += sstep;
t += tstep;
izi += izistep;
*pdest++ = pix;
}while(--spancount);
}
static inline void
dospan_solid_f1(pixel_t *pdest, pixel_t *pbase, int s, int t, int sstep, int tstep, int spancount, int width, uzint *pz, uzint izi, int izistep, fog_t *fog)
{
pixel_t pix;
do{
*pz++ = izi;
izi += izistep;
pix = pbase[(s >> 16) + (t >> 16) * width];
s += sstep;
t += tstep;
*pdest++ = blendfog(pix, *fog);
fogstep(*fog);
}while(--spancount);
}
static inline void
dospan_blend(pixel_t *pdest, pixel_t *pbase, int s, int t, int sstep, int tstep, int spancount, int width, byte alpha, uzint *pz, uzint izi, int izistep)
{
pixel_t pix;
do{
pix = pbase[(s >> 16) + (t >> 16) * width];
s += sstep;
t += tstep;
if(opaque(pix) && *pz <= izi)
*pdest = blendalpha(pix, *pdest, alpha);
izi += izistep;
pdest++;
pz++;
}while(--spancount);
}
static inline void
dospan_blend_f1(pixel_t *pdest, pixel_t *pbase, int s, int t, int sstep, int tstep, int spancount, int width, byte alpha, uzint *pz, uzint izi, int izistep, fog_t *fog)
{
pixel_t pix;
do{
pix = pbase[(s >> 16) + (t >> 16) * width];
s += sstep;
t += tstep;
if(opaque(pix) && *pz <= izi)
*pdest = blendalpha(blendfog(pix, *fog), *pdest, alpha);
izi += izistep;
pdest++;
pz++;
fogstep(*fog);
}while(--spancount);
}
static inline void
dospan_fence(pixel_t *pdest, pixel_t *pbase, int s, int t, int sstep, int tstep, int spancount, int width, uzint *pz, uzint izi, int izistep)
{
pixel_t pix;
do{
pix = pbase[(s >> 16) + (t >> 16) * width];
s += sstep;
t += tstep;
if(opaque(pix) && *pz <= izi){
*pdest = pix;
*pz = izi;
}
izi += izistep;
pdest++;
pz++;
}while(--spancount);
}
static inline void
dospan_fence_f1(pixel_t *pdest, pixel_t *pbase, int s, int t, int sstep, int tstep, int spancount, int width, uzint *pz, uzint izi, int izistep, fog_t *fog)
{
pixel_t pix;
do{
pix = pbase[(s >> 16) + (t >> 16) * width];
s += sstep;
t += tstep;
if(opaque(pix) && *pz <= izi){
*pdest = blendfog(pix, *fog);
*pz = izi;
}
izi += izistep;
pdest++;
pz++;
fogstep(*fog);
}while(--spancount);
}
static void
dospan_turb(pixel_t *pdest, pixel_t *pbase, int s, int t, int sstep, int tstep, int spancount, byte alpha, uzint *pz, uzint izi, int izistep)
{
int sturb, tturb;
bool noblend;
noblend = (r_drawflags & DRAW_BLEND) == 0;
s &= (CYCLE<<16)-1;
t &= (CYCLE<<16)-1;
do{
if(noblend || *pz <= izi){
sturb = ((s + r_turb_turb[(t>>16)&(CYCLE-1)])>>16)&63;
tturb = ((t + r_turb_turb[(s>>16)&(CYCLE-1)])>>16)&63;
*pdest = blendalpha(*(pbase + (tturb<<6) + sturb), *pdest, alpha);
*pz = izi; // FIXME(sigrid): can always update this one?
}
s += sstep;
t += tstep;
izi += izistep;
pdest++;
pz++;
}while(--spancount > 0);
}
static void
dospan_turb_f1(pixel_t *pdest, pixel_t *pbase, int s, int t, int sstep, int tstep, int spancount, byte alpha, uzint *pz, uzint izi, int izistep, fog_t *fog)
{
int sturb, tturb;
bool noblend;
noblend = (r_drawflags & DRAW_BLEND) == 0;
s &= (CYCLE<<16)-1;
t &= (CYCLE<<16)-1;
do{
if(noblend || *pz <= izi){
sturb = ((s + r_turb_turb[(t>>16)&(CYCLE-1)])>>16)&63;
tturb = ((t + r_turb_turb[(s>>16)&(CYCLE-1)])>>16)&63;
*pdest = blendalpha(blendfog(*(pbase + (tturb<<6) + sturb), *fog), *pdest, alpha);
*pz = izi; // FIXME(sigrid): can always update this one?
}
s += sstep;
t += tstep;
izi += izistep;
pdest++;
pz++;
fogstep(*fog);
}while(--spancount > 0);
}
void
D_DrawSpans16(espan_t *pspan, pixel_t *pbase, int width, byte alpha, int spanfunc)
{
int count, spancount, izistep, spancountminus1;
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;
sstep = 0; // keep compiler happy
tstep = 0; // ditto
memset(&fog, 0, sizeof(fog));
sdivzstepu = dvars.sdivzstepu * 16;
tdivzstepu = dvars.tdivzstepu * 16;
zistepu = dvars.zistepu * 16;
izistep = (int)(dvars.zistepu * 0x8000 * 0x10000);
do{
pdest = dvars.viewbuffer + pspan->v*dvars.width + pspan->u;
pz = dvars.zbuffer + pspan->v*dvars.width + pspan->u;
zi = dvars.ziorigin + pspan->v*dvars.zistepv + pspan->u*dvars.zistepu;
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 = dvars.sdivzorigin + dv*dvars.sdivzstepv + du*dvars.sdivzstepu;
tdivz = dvars.tdivzorigin + dv*dvars.tdivzstepv + du*dvars.tdivzstepu;
z = (float)0x10000 / zi; // prescale to 16.16 fixed-point
s = (int)(sdivz * z) + dvars.sadjust;
s = clamp(s, 0, dvars.bbextents);
t = (int)(tdivz * z) + dvars.tadjust;
t = clamp(t, 0, dvars.bbextentt);
do{
// calculate s and t at the far end of the span
spancount = min(count, 16);
count -= spancount;
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)0x10000 / (zi + zistepu);
snext = (int)(sdivz * z) + dvars.sadjust;
// prevent round-off error on <0 steps from
// from causing overstepping & running off the
// edge of the texture
snext = clamp(snext, 16, dvars.bbextents);
tnext = (int)(tdivz * z) + dvars.tadjust;
// guard against round-off error on <0 steps
tnext = clamp(tnext, 16, dvars.bbextentt);
sstep = (snext - s) >> 4;
tstep = (tnext - t) >> 4;
}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 += dvars.sdivzstepu * spancountminus1;
tdivz += dvars.tdivzstepu * spancountminus1;
// prescale to 16.16 fixed-point
z = (float)0x10000 / (zi + dvars.zistepu * spancountminus1);
snext = (int)(sdivz * z) + dvars.sadjust;
// prevent round-off error on <0 steps from
// from causing overstepping & running off the
// edge of the texture
snext = clamp(snext, 16, dvars.bbextents);
tnext = (int)(tdivz * z) + dvars.tadjust;
// guard against round-off error on <0 steps
tnext = clamp(tnext, 16, dvars.bbextentt);
if(spancount > 1){
sstep = (snext - s) / spancountminus1;
tstep = (tnext - t) / spancountminus1;
}
}
fogged = isfogged() ? fogcalc(izi, izi + izistep*spancount, spancount, &fog) : false;
if(fogged){
switch(spanfunc){
case SPAN_SOLID:
dospan_solid_f1(pdest, pbase, s, t, sstep, tstep, spancount, width, 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, width, alpha, pz, izi, izistep, &fog);
break;
case SPAN_FENCE:
dospan_fence_f1(pdest, pbase, s, t, sstep, tstep, spancount, width, pz, izi, izistep, &fog);
break;
}
}else{
switch(spanfunc){
case SPAN_SOLID:
dospan_solid(pdest, pbase, s, t, sstep, tstep, spancount, width, 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, width, alpha, pz, izi, izistep);
break;
case SPAN_FENCE:
dospan_fence(pdest, pbase, s, t, sstep, tstep, spancount, width, 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);
}