ref: 4ccf8bb9ef7dcfda6d7e0ab172df2dbdae74110c
dir: /d_scan.c/
#include "quakedef.h"
static pixel_t *r_turb_pbase, *r_turb_pdest;
static fixed16_t r_turb_s, r_turb_t, r_turb_sstep, r_turb_tstep;
static int *r_turb_turb;
static int r_turb_spancount;
static uzint *r_turb_z;
/*
=============
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)
{
int w, h, u, v, *turb, *col;
pixel_t *dest;
pixel_t **row;
float wratio, hratio;
static pixel_t *rowptr[MAXHEIGHT+(AMP2*2)];
static int column[MAXWIDTH+(AMP2*2)];
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]];
}
}
}
/*
=============
D_DrawTurbulent8Span
=============
*/
static inline void
D_DrawTurbulent8Span (int izi, byte alpha)
{
int sturb, tturb;
do{
sturb = ((r_turb_s + r_turb_turb[(r_turb_t>>16)&(CYCLE-1)])>>16)&63;
tturb = ((r_turb_t + r_turb_turb[(r_turb_s>>16)&(CYCLE-1)])>>16)&63;
if(*r_turb_z <= izi || (r_drawflags & DRAW_BLEND) == 0)
*r_turb_pdest = blendalpha(*(r_turb_pbase + (tturb<<6) + sturb), *r_turb_pdest, alpha, izi);
r_turb_s += r_turb_sstep;
r_turb_t += r_turb_tstep;
r_turb_pdest++;
r_turb_z++;
}while(--r_turb_spancount > 0);
}
void
Turbulent8(espan_t *pspan, byte alpha)
{
int count, spancountminus1;
fixed16_t snext, tnext;
float sdivz, tdivz, zi, z, du, dv;
float sdivz16stepu, tdivz16stepu, zi16stepu;
r_turb_turb = sintable + ((int)(cl.time*SPEED)&(CYCLE-1));
r_turb_sstep = 0; // keep compiler happy
r_turb_tstep = 0; // ditto
r_turb_pbase = dvars.cacheblock;
sdivz16stepu = dvars.sdivzstepu * 16;
tdivz16stepu = dvars.tdivzstepu * 16;
zi16stepu = dvars.zistepu * 16;
do{
r_turb_pdest = dvars.viewbuffer + pspan->v*dvars.width + pspan->u;
r_turb_z = dvars.zbuffer + pspan->v*dvars.width + pspan->u;
zi = dvars.ziorigin + pspan->v*dvars.zistepv + pspan->u*dvars.zistepu;
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
r_turb_s = (int)(sdivz * z) + dvars.sadjust;
r_turb_s = clamp(r_turb_s, 0, dvars.bbextents);
r_turb_t = (int)(tdivz * z) + dvars.tadjust;
r_turb_t = clamp(r_turb_t, 0, dvars.bbextentt);
do{
// calculate s and t at the far end of the span
r_turb_spancount = min(count, 16);
count -= r_turb_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 += sdivz16stepu;
tdivz += tdivz16stepu;
zi += zi16stepu;
z = (float)0x10000 / zi; // prescale to 16.16 fixed-point
snext = (int)(sdivz * z) + dvars.sadjust;
// prevent round-off error on <0 steps from causing overstepping & running off the edge of the texture
snext = clamp(snext, 16, dvars.bbextents);
tnext = (int)(tdivz * z) + dvars.tadjust;
tnext = clamp(tnext, 16, dvars.bbextentt); // guard against round-off error on <0 steps
r_turb_sstep = (snext - r_turb_s) >> 4;
r_turb_tstep = (tnext - r_turb_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 = r_turb_spancount - 1;
sdivz += dvars.sdivzstepu * spancountminus1;
tdivz += dvars.tdivzstepu * spancountminus1;
zi += dvars.zistepu * spancountminus1;
z = (float)0x10000 / zi; // prescale to 16.16 fixed-point
snext = (int)(sdivz * z) + dvars.sadjust;
// prevent round-off error on <0 steps from causing overstepping & running off the edge of the texture
snext = clamp(snext, 16, dvars.bbextents);
tnext = (int)(tdivz * z) + dvars.tadjust;
tnext = clamp(tnext, 16, dvars.bbextentt); // guard against round-off error on <0 steps
if(r_turb_spancount > 1){
r_turb_sstep = (snext - r_turb_s) / spancountminus1;
r_turb_tstep = (tnext - r_turb_t) / spancountminus1;
}
}
r_turb_s = r_turb_s & ((CYCLE<<16)-1);
r_turb_t = r_turb_t & ((CYCLE<<16)-1);
D_DrawTurbulent8Span((int)(zi * 0x8000 * 0x10000), alpha);
r_turb_s = snext;
r_turb_t = tnext;
}while(count > 0);
}while((pspan = pspan->pnext) != nil);
}
void
D_DrawSpans16(espan_t *pspan, bool blend, byte alpha) //qbism- up it from 8 to 16
{
int count, spancount, izistep, spancountminus1;
pixel_t *pbase, *pdest;
uzint *pz;
fixed16_t s, t, snext, tnext, sstep, tstep;
float sdivz, tdivz, zi, z, du, dv;
float sdivzstepu, tdivzstepu, zistepu;
sstep = 0; // keep compiler happy
tstep = 0; // ditto
pbase = dvars.cacheblock;
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;
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;
z = (float)0x10000 / (zi + zistepu); // prescale to 16.16 fixed-point
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;
z = (float)0x10000 / (zi + dvars.zistepu * spancountminus1); // prescale to 16.16 fixed-point
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;
}
}
void dospan(pixel_t *, pixel_t *, int, int, int, int, int, int);
void dospan_alpha(pixel_t *, pixel_t *, int, int, int, int, int, int, byte, uzint *, int, int);
if(blend)
dospan_alpha(pdest, pbase, s, t, sstep, tstep, spancount, dvars.cachewidth, alpha, pz, (int)(zi * 0x8000 * 0x10000), izistep);
else
dospan(pdest, pbase, s, t, sstep, tstep, spancount, dvars.cachewidth);
pdest += spancount;
pz += spancount;
zi += zistepu;
s = snext;
t = tnext;
}while(count > 0);
}while((pspan = pspan->pnext) != nil);
}
void
D_DrawZSpans(espan_t *pspan)
{
int count, spancount, izi, izistep;
uzint *pz;
float zi;
float zistepu;
zistepu = dvars.zistepu * 16;
izistep = dvars.zistepu * 0x8000 * 0x10000;
do{
pz = dvars.zbuffer + pspan->v*dvars.width + pspan->u;
zi = dvars.ziorigin + pspan->v*dvars.zistepv + pspan->u*dvars.zistepu;
count = pspan->count;
do{
spancount = min(count, 16);
count -= spancount;
izi = (int)(zi * 0x8000 * 0x10000);
while(spancount-- > 0){
*pz++ = izi;
izi += izistep;
}
zi += zistepu;
}while(count > 0);
}while((pspan = pspan->pnext) != nil);
}