quakeforge/libs/video/renderer/sw/d_sky.c
Bill Currie 6377734e32 [renderer] Merge the two software renderers
I got tired of having to maintain two separate software renderers, but
didn't want to just nuke sw32, so its core changes are merged into sw.

Alias model rendering is broken, but I know exactly what's wrong and how
to fix it, just need to take care due to asm.
2022-03-09 15:56:19 +09:00

274 lines
6.3 KiB
C

/*
d_sky.c
(description)
Copyright (C) 1996-1997 Id Software, Inc.
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "QF/render.h"
#include "d_local.h"
#include "r_internal.h"
#include "vid_sw.h"
#define SKY_SPAN_SHIFT 5
#define SKY_SPAN_MAX (1 << SKY_SPAN_SHIFT)
static void
D_Sky_uv_To_st (int u, int v, fixed16_t *s, fixed16_t *t)
{
float wu, wv, temp;
vec3_t end;
int half_width = vid.width >> 1;
int half_height = vid.height >> 1;
if (r_refdef.vrect.width >= r_refdef.vrect.height)
temp = (float) r_refdef.vrect.width;
else
temp = (float) r_refdef.vrect.height;
wu = 8192.0 * (float) (u - half_width) / temp;
wv = 8192.0 * (float) (half_height - v) / temp;
end[0] = 4096 * vpn[0] + wu * vright[0] + wv * vup[0];
end[1] = 4096 * vpn[1] + wu * vright[1] + wv * vup[1];
end[2] = 4096 * vpn[2] + wu * vright[2] + wv * vup[2];
end[2] *= 3;
VectorNormalize (end);
temp = r_skytime * r_skyspeed; // TODO: add D_SetupFrame & set this there
*s = (int) ((temp + 6 * (SKYSIZE / 2 - 1) * end[0]) * 0x10000);
*t = (int) ((temp + 6 * (SKYSIZE / 2 - 1) * end[1]) * 0x10000);
}
void
draw_sky_scans_8 (espan_t *pspan)
{
int count, spancount, u, v;
unsigned char *pdest;
fixed16_t s, t, snext, tnext, sstep, tstep;
int spancountminus1;
sstep = 0; // keep compiler happy
tstep = 0; // ditto
snext = 0; // ditto
tnext = 0; // ditto
do {
pdest = (unsigned char *) ((byte *) d_viewbuffer +
(screenwidth * pspan->v) + pspan->u);
count = pspan->count;
// calculate the initial s & t
u = pspan->u;
v = pspan->v;
D_Sky_uv_To_st (u, v, &s, &t);
do {
if (count >= SKY_SPAN_MAX)
spancount = SKY_SPAN_MAX;
else
spancount = count;
count -= spancount;
if (count) {
u += spancount;
// calculate s and t at far end of span,
// calculate s and t steps across span by shifting
D_Sky_uv_To_st (u, v, &snext, &tnext);
sstep = (snext - s) >> SKY_SPAN_SHIFT;
tstep = (tnext - t) >> SKY_SPAN_SHIFT;
} else {
// calculate s and t at last pixel in span,
// calculate s and t steps across span by division
spancountminus1 = (float) (spancount - 1);
if (spancountminus1 > 0) {
u += spancountminus1;
D_Sky_uv_To_st (u, v, &snext, &tnext);
sstep = (snext - s) / spancountminus1;
tstep = (tnext - t) / spancountminus1;
}
}
do {
*pdest++ = r_skysource[((t & R_SKY_TMASK) >> 8) +
((s & R_SKY_SMASK) >> 16)];
s += sstep;
t += tstep;
} while (--spancount > 0);
s = snext;
t = tnext;
} while (count > 0);
} while ((pspan = pspan->pnext) != NULL);
}
void
draw_sky_scans_16 (espan_t *pspan)
{
int count, spancount, u, v;
short *pdest;
fixed16_t s, t, snext, tnext, sstep, tstep;
int spancountminus1;
sstep = 0; // keep compiler happy
tstep = 0; // ditto
snext = 0; // ditto
tnext = 0; // ditto
do {
pdest = (short *) d_viewbuffer + screenwidth * pspan->v + pspan->u;
count = pspan->count;
// calculate the initial s & t
u = pspan->u;
v = pspan->v;
D_Sky_uv_To_st (u, v, &s, &t);
do {
if (count >= SKY_SPAN_MAX)
spancount = SKY_SPAN_MAX;
else
spancount = count;
count -= spancount;
if (count) {
u += spancount;
// calculate s and t at far end of span,
// calculate s and t steps across span by shifting
D_Sky_uv_To_st (u, v, &snext, &tnext);
sstep = (snext - s) >> SKY_SPAN_SHIFT;
tstep = (tnext - t) >> SKY_SPAN_SHIFT;
} else {
// calculate s and t at last pixel in span,
// calculate s and t steps across span by division
spancountminus1 = (float) (spancount - 1);
if (spancountminus1 > 0) {
u += spancountminus1;
D_Sky_uv_To_st (u, v, &snext, &tnext);
sstep = (snext - s) / spancountminus1;
tstep = (tnext - t) / spancountminus1;
}
}
do {
*pdest++ = ((short *) r_skysource)
[((t & R_SKY_TMASK) >> 8) + ((s & R_SKY_SMASK) >> 16)];
s += sstep;
t += tstep;
} while (--spancount > 0);
s = snext;
t = tnext;
} while (count > 0);
} while ((pspan = pspan->pnext) != NULL);
}
void
draw_sky_scans_32 (espan_t *pspan)
{
int count, spancount, u, v;
int *pdest;
fixed16_t s, t, snext, tnext, sstep, tstep;
int spancountminus1;
sstep = 0; // keep compiler happy
tstep = 0; // ditto
snext = 0; // ditto
tnext = 0; // ditto
do {
pdest = (int *) d_viewbuffer + screenwidth * pspan->v + pspan->u;
count = pspan->count;
// calculate the initial s & t
u = pspan->u;
v = pspan->v;
D_Sky_uv_To_st (u, v, &s, &t);
do {
if (count >= SKY_SPAN_MAX)
spancount = SKY_SPAN_MAX;
else
spancount = count;
count -= spancount;
if (count) {
u += spancount;
// calculate s and t at far end of span,
// calculate s and t steps across span by shifting
D_Sky_uv_To_st (u, v, &snext, &tnext);
sstep = (snext - s) >> SKY_SPAN_SHIFT;
tstep = (tnext - t) >> SKY_SPAN_SHIFT;
} else {
// calculate s and t at last pixel in span,
// calculate s and t steps across span by division
spancountminus1 = (float) (spancount - 1);
if (spancountminus1 > 0) {
u += spancountminus1;
D_Sky_uv_To_st (u, v, &snext, &tnext);
sstep = (snext - s) / spancountminus1;
tstep = (tnext - t) / spancountminus1;
}
}
do {
*pdest++ = ((int *) r_skysource)
[((t & R_SKY_TMASK) >> 8) + ((s & R_SKY_SMASK) >> 16)];
s += sstep;
t += tstep;
} while (--spancount > 0);
s = snext;
t = tnext;
} while (count > 0);
} while ((pspan = pspan->pnext) != NULL);
}