quakeforge-old/uquake/d_sky.c
Jeff Teunissen c3f5581b0a Created new subdir: uquake. Pick your favorite U word for the meaning --
Unchained, Ultimate, Ultra, Up Yours, Underworld, Underground, Unified,
Unity, etc. You know the drill.

This takes care of the "standalone" problem with the wrong name, and the
recent snafu with multiple developers working on the same files
simultaneously...expect me (and probably others) to start locking dirs when
updates are taking place.

And yes, this update is really as large as it looks. Software only at the
moment, but I will have the makefile updated to build the GL builds as
well.
1999-12-26 13:51:52 +00:00

138 lines
3.1 KiB
C

/*
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 the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
// d_sky.c
#include "quakedef.h"
#include "r_local.h"
#include "d_local.h"
#define SKY_SPAN_SHIFT 5
#define SKY_SPAN_MAX (1 << SKY_SPAN_SHIFT)
/*
=================
D_Sky_uv_To_st
=================
*/
void D_Sky_uv_To_st (int u, int v, fixed16_t *s, fixed16_t *t)
{
float wu, wv, temp;
vec3_t end;
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-((int)vid.width>>1)) / temp;
wv = 8192.0 * (float)(((int)vid.height>>1)-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 = skytime*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);
}
/*
=================
D_DrawSkyScans8
=================
*/
void D_DrawSkyScans8 (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
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);
}