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quakeforge-old/common/gl_warp.c
Zephaniah E. Hull 41c969c2ac LoadPCX has been rewritten and now functions!!
2000-03-04 20:32:38 +00:00

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/*
gl_warp.c
Sky and water polygons
Copyright (C) 1996-1997 Id Software, Inc.
Copyright (C) 1999,2000 contributors of the QuakeForge project
Please see the file "AUTHORS" for a list of contributors
Portions Copyright (C) 1999,2000 Nelson Rush.
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
*/
#include <qtypes.h>
#include <quakedef.h>
#include <glquake.h>
#include <mathlib.h>
#include <sys.h>
#include <console.h>
extern model_t *loadmodel;
int skytexturenum;
int solidskytexture;
int alphaskytexture;
float speedscale; // for top sky and bottom sky
msurface_t *warpface;
extern cvar_t *gl_subdivide_size;
/*
BoundPoly (int, float, vec3_t, vec3_t)
*/
void
BoundPoly (int numverts, float *verts, vec3_t mins, vec3_t maxs) {
int i, j;
float *v;
mins[0] = mins[1] = mins[2] = 9999;
maxs[0] = maxs[1] = maxs[2] = -9999;
v = verts;
for (i=0 ; i<numverts ; i++)
for (j=0 ; j<3 ; j++, v++) {
if (*v < mins[j])
mins[j] = *v;
if (*v > maxs[j])
maxs[j] = *v;
}
}
void
SubdividePolygon ( int numverts, float *verts ) {
int i, j, k;
vec3_t mins, maxs;
float m;
float *v;
vec3_t front[64], back[64];
int f, b;
float dist[64];
float frac;
glpoly_t *poly;
float s, t;
if (numverts > 60)
Sys_Error ("numverts = %i", numverts);
BoundPoly (numverts, verts, mins, maxs);
for (i=0 ; i<3 ; i++) {
m = (mins[i] + maxs[i]) * 0.5;
m = gl_subdivide_size->value * floor (m/gl_subdivide_size->value + 0.5);
if (maxs[i] - m < 8)
continue;
if (m - mins[i] < 8)
continue;
// cut it
v = verts + i;
for (j=0 ; j<numverts ; j++, v+= 3)
dist[j] = *v - m;
// wrap cases
dist[j] = dist[0];
v-=i;
VectorCopy (verts, v);
f = b = 0;
v = verts;
for (j=0 ; j<numverts ; j++, v+= 3) {
if (dist[j] >= 0) {
VectorCopy (v, front[f]);
f++;
}
if (dist[j] <= 0) {
VectorCopy (v, back[b]);
b++;
}
if (dist[j] == 0 || dist[j+1] == 0)
continue;
if ( (dist[j] > 0) != (dist[j+1] > 0) ) {
// clip point
frac = dist[j] / (dist[j] - dist[j+1]);
for (k=0 ; k<3 ; k++)
front[f][k] = back[b][k] = v[k] + frac*(v[3+k] - v[k]);
f++;
b++;
}
}
SubdividePolygon (f, front[0]);
SubdividePolygon (b, back[0]);
return;
}
poly = Hunk_Alloc (sizeof(glpoly_t) + (numverts-4) * VERTEXSIZE*sizeof(float));
poly->next = warpface->polys;
warpface->polys = poly;
poly->numverts = numverts;
for (i=0 ; i<numverts ; i++, verts+= 3) {
VectorCopy (verts, poly->verts[i]);
s = DotProduct (verts, warpface->texinfo->vecs[0]);
t = DotProduct (verts, warpface->texinfo->vecs[1]);
poly->verts[i][3] = s;
poly->verts[i][4] = t;
}
}
/*
GL_SubdivideSurface
Break a polygon up along axial 64 unit boundaries so that turbulent
and sky warps can be done reasonably.
*/
void
GL_SubdivideSurface (msurface_t *fa) {
vec3_t verts[64];
int numverts;
int i;
int lindex;
float *vec;
warpface = fa;
/*
convert edges back to a normal polygon
*/
numverts = 0;
for (i=0 ; i<fa->numedges ; i++) {
lindex = loadmodel->surfedges[fa->firstedge + i];
if (lindex > 0)
vec = loadmodel->vertexes[loadmodel->edges[lindex].v[0]].position;
else
vec = loadmodel->vertexes[loadmodel->edges[-lindex].v[1]].position;
VectorCopy (vec, verts[numverts]);
numverts++;
}
SubdividePolygon (numverts, verts[0]);
}
//=========================================================
// speed up sin calculations - Ed
float turbsin[] = {
#include "gl_warp_sin.-c"
};
#define TURBSCALE (256.0 / (2 * M_PI))
/*
EmitWaterPolys
Do a water warp on the pre-fragmented glpoly_t chain
*/
void
EmitWaterPolys ( msurface_t *fa ) {
glpoly_t *p;
float *v;
int i;
float s, t, os, ot;
vec3_t nv;
for (p=fa->polys ; p ; p=p->next) {
glBegin (GL_POLYGON);
for (i=0,v=p->verts[0] ; i<p->numverts ; i++, v+=VERTEXSIZE) {
os = v[3];
ot = v[4];
s = os + turbsin[(int)((ot*0.125+realtime) * TURBSCALE) & 255];
s *= (1.0/64);
t = ot + turbsin[(int)((os*0.125+realtime) * TURBSCALE) & 255];
t *= (1.0/64);
glTexCoord2f (s, t);
if(r_waterripple->value) {
nv[0] = v[0]; //+8*sin(v[1]*0.05+realtime)*sin(v[2]*0.05+realtime);
nv[1] = v[1]; //+8*sin(v[0]*0.05+realtime)*sin(v[2]*0.05+realtime);
nv[2] = v[2] + r_waterripple->value*sin(v[0]*0.05+realtime)*sin(v[2]*0.05+realtime);
glVertex3fv (nv);
} else {
glVertex3fv (v);
}
}
glEnd ();
}
}
/*
EmitSkyPolys
*/
void
EmitSkyPolys ( msurface_t *fa ) {
glpoly_t *p;
float *v;
int i;
float s, t;
vec3_t dir;
float length;
for (p=fa->polys ; p ; p=p->next)
{
glBegin (GL_POLYGON);
for (i=0,v=p->verts[0] ; i<p->numverts ; i++, v+=VERTEXSIZE)
{
VectorSubtract (v, r_origin, dir);
dir[2] *= 3; // flatten the sphere
length = dir[0]*dir[0] + dir[1]*dir[1] + dir[2]*dir[2];
length = sqrt (length);
length = 6*63/length;
dir[0] *= length;
dir[1] *= length;
s = (speedscale + dir[0]) * (1.0/128);
t = (speedscale + dir[1]) * (1.0/128);
glTexCoord2f (s, t);
glVertex3fv (v);
}
glEnd ();
}
}
/*
EmitBothSkyLayers
Do a sky warp on the pre-fragmented glpoly_t chain. This will be
called for brushmodels, the world will have them chained together.
*/
void
EmitBothSkyLayers ( msurface_t *fa ) {
GL_DisableMultitexture();
GL_Bind (solidskytexture);
speedscale = realtime*8;
speedscale -= (int)speedscale & ~127 ;
EmitSkyPolys (fa);
glEnable (GL_BLEND);
GL_Bind (alphaskytexture);
speedscale = realtime*16;
speedscale -= (int)speedscale & ~127 ;
EmitSkyPolys (fa);
glDisable (GL_BLEND);
}
/*
Quake 2 sky rendering ("skyboxes")
*/
#define SKY_TEX 2000
#if 0
/*
LoadPCX
*/
void
LoadPCX (QFile *f, byte **pcx_rgb)
{
pcx_t *pcx, pcxbuf;
byte palette[768];
byte *pix;
int x, y;
int dataByte, runLength;
int count;
/*
Parse PCX file
*/
Qread (f, &pcxbuf, sizeof(pcxbuf));
pcx = &pcxbuf;
if (pcx->manufacturer != 0x0a || pcx->version != 5 || pcx->encoding != 1
|| pcx->bits_per_pixel != 8 || pcx->xmax >= 320
|| pcx->ymax >= 256) {
Con_Printf ("Bad PCX file\n");
return;
}
// seek to palette
Qseek (f, -768, SEEK_END);
Qread (f, palette, 768);
Qseek (f, sizeof(pcxbuf) - 4, SEEK_SET);
count = (pcx->xmax+1) * (pcx->ymax+1);
*pcx_rgb = malloc( count * 4);
for (y=0 ; y<=pcx->ymax ; y++) {
pix = *pcx_rgb + 4*y*(pcx->xmax+1);
for (x=0 ; x<=pcx->ymax ; ) {
dataByte = Qgetc(f);
if((dataByte & 0xC0) == 0xC0) {
runLength = dataByte & 0x3F;
dataByte = Qgetc(f);
}
else
runLength = 1;
while(runLength-- > 0) {
pix[0] = palette[dataByte*3];
pix[1] = palette[dataByte*3+1];
pix[2] = palette[dataByte*3+2];
pix[3] = 255;
pix += 4;
x++;
}
}
}
}
#endif
/*
TARGA LOADING
*/
typedef struct _TargaHeader {
unsigned char id_length, colormap_type, image_type;
unsigned short colormap_index, colormap_length;
unsigned char colormap_size;
unsigned short x_origin, y_origin, width, height;
unsigned char pixel_size, attributes;
} TargaHeader;
int
QgetLittleShort ( QFile *f ) {
byte b1, b2;
b1 = Qgetc(f);
b2 = Qgetc(f);
return (short)(b1 + b2*256);
}
int
QgetLittleLong (QFile *f) {
byte b1, b2, b3, b4;
b1 = Qgetc(f);
b2 = Qgetc(f);
b3 = Qgetc(f);
b4 = Qgetc(f);
return b1 + (b2<<8) + (b3<<16) + (b4<<24);
}
/*
LoadTGA
*/
void
LoadTGA (QFile *fin, byte **targa_rgba) {
int columns, rows, numPixels;
byte *pixbuf;
int row, column;
TargaHeader targa_header;
unsigned char red = 0, green = 0, blue = 0, alphabyte = 0;
targa_header.id_length = Qgetc(fin);
targa_header.colormap_type = Qgetc(fin);
targa_header.image_type = Qgetc(fin);
targa_header.colormap_index = QgetLittleShort(fin);
targa_header.colormap_length = QgetLittleShort(fin);
targa_header.colormap_size = Qgetc(fin);
targa_header.x_origin = QgetLittleShort(fin);
targa_header.y_origin = QgetLittleShort(fin);
targa_header.width = QgetLittleShort(fin);
targa_header.height = QgetLittleShort(fin);
targa_header.pixel_size = Qgetc(fin);
targa_header.attributes = Qgetc(fin);
if (targa_header.image_type!=2 && targa_header.image_type!=10)
Sys_Error ("LoadTGA: Only type 2 and 10 targa RGB images supported\n");
if (targa_header.colormap_type !=0 ||
(targa_header.pixel_size!=32 && targa_header.pixel_size!=24)) {
Sys_Error ("Texture_LoadTGA: Only 32 or 24 bit images supported (no colormaps)\n");
}
columns = targa_header.width;
rows = targa_header.height;
numPixels = columns * rows;
*targa_rgba = malloc (numPixels*4);
if (targa_header.id_length != 0)
Qseek(fin, targa_header.id_length, SEEK_CUR); // skip TARGA image comment
if (targa_header.image_type==2) { // Uncompressed, RGB images
for(row=rows-1; row>=0; row--) {
pixbuf = *targa_rgba + row*columns*4;
for(column=0; column<columns; column++) {
switch (targa_header.pixel_size) {
case 24:
blue = Qgetc(fin);
green = Qgetc(fin);
red = Qgetc(fin);
*pixbuf++ = red;
*pixbuf++ = green;
*pixbuf++ = blue;
*pixbuf++ = 255;
break;
case 32:
blue = Qgetc(fin);
green = Qgetc(fin);
red = Qgetc(fin);
alphabyte = Qgetc(fin);
*pixbuf++ = red;
*pixbuf++ = green;
*pixbuf++ = blue;
*pixbuf++ = alphabyte;
break;
}
}
}
}
else if (targa_header.image_type==10) { // Runlength encoded RGB images
unsigned char packetHeader,packetSize,j;
for(row=rows-1; row>=0; row--) {
pixbuf = *targa_rgba + row*columns*4;
for(column=0; column<columns; ) {
packetHeader=Qgetc(fin);
packetSize = 1 + (packetHeader & 0x7f);
if (packetHeader & 0x80) { // run-length packet
switch (targa_header.pixel_size) {
case 24:
blue = Qgetc(fin);
green = Qgetc(fin);
red = Qgetc(fin);
alphabyte = 255;
break;
case 32:
blue = Qgetc(fin);
green = Qgetc(fin);
red = Qgetc(fin);
alphabyte = Qgetc(fin);
break;
}
for(j=0;j<packetSize;j++) {
*pixbuf++=red;
*pixbuf++=green;
*pixbuf++=blue;
*pixbuf++=alphabyte;
column++;
if (column==columns) { // run spans across rows
column=0;
if (row>0)
row--;
else
goto breakOut;
pixbuf = *targa_rgba + row*columns*4;
}
}
}
else { // non run-length packet
for(j=0;j<packetSize;j++) {
switch (targa_header.pixel_size) {
case 24:
blue = Qgetc(fin);
green = Qgetc(fin);
red = Qgetc(fin);
*pixbuf++ = red;
*pixbuf++ = green;
*pixbuf++ = blue;
*pixbuf++ = 255;
break;
case 32:
blue = Qgetc(fin);
green = Qgetc(fin);
red = Qgetc(fin);
alphabyte = Qgetc(fin);
*pixbuf++ = red;
*pixbuf++ = green;
*pixbuf++ = blue;
*pixbuf++ = alphabyte;
break;
}
column++;
if (column==columns) { // pixel packet run spans across rows
column=0;
if (row>0)
row--;
else
goto breakOut;
pixbuf = *targa_rgba + row*columns*4;
}
}
}
}
breakOut:;
}
}
Qclose(fin);
// fclose(fin);
}
/*
R_LoadSkys
*/
char *suf[6] = {"rt", "bk", "lf", "ft", "up", "dn"};
void
R_LoadSkys ( void ) {
int i;
QFile *f;
byte *skyimage = NULL;
char name[64];
for (i=0 ; i<6 ; i++) {
GL_Bind (SKY_TEX + i);
snprintf(name, sizeof(name), "gfx/env/%s%s.tga",
// snprintf(name, sizeof(name), "gfx/env/%s%s.pcx",
r_skyname->string, suf[i]);
COM_FOpenFile (name, &f);
if (!f) {
Con_Printf ("Couldn't load %s\n", name);
continue;
}
LoadTGA (f, &skyimage);
// LoadPCX (f, &skyimage);
glTexImage2D (GL_TEXTURE_2D, 0, gl_solid_format, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, skyimage);
// glTexImage2D (GL_TEXTURE_2D, 0, gl_solid_format, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, pcx_rgb);
// free (targa_rgba);
free (skyimage);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}
}
vec3_t skyclip[6] = {
{1,1,0},
{1,-1,0},
{0,-1,1},
{0,1,1},
{1,0,1},
{-1,0,1}
};
int c_sky;
// 1 = s, 2 = t, 3 = 2048
int st_to_vec[6][3] = {
{3,-1,2},
{-3,1,2},
{1,3,2},
{-1,-3,2},
{-2,-1,3}, // 0 degrees yaw, look straight up
{2,-1,-3} // look straight down
// {-1,2,3},
// {1,2,-3}
};
// s = [0]/[2], t = [1]/[2]
int vec_to_st[6][3] = {
{-2,3,1},
{2,3,-1},
{1,3,2},
{-1,3,-2},
{-2,-1,3},
{-2,1,-3}
// {-1,2,3},
// {1,2,-3}
};
float skymins[2][6], skymaxs[2][6];
void
DrawSkyPolygon (int nump, vec3_t vecs) {
int i,j;
vec3_t v, av;
float s, t, dv;
int axis;
float *vp;
c_sky++;
#if 0
glBegin (GL_POLYGON);
for (i=0 ; i<nump ; i++, vecs+=3) {
VectorAdd(vecs, r_origin, v);
glVertex3fv (v);
}
glEnd();
return;
#endif
// decide which face it maps to
VectorCopy (vec3_origin, v);
for (i=0, vp=vecs ; i<nump ; i++, vp+=3) {
VectorAdd (vp, v, v);
}
av[0] = fabs(v[0]);
av[1] = fabs(v[1]);
av[2] = fabs(v[2]);
if (av[0] > av[1] && av[0] > av[2]) {
if (v[0] < 0)
axis = 1;
else
axis = 0;
} else if (av[1] > av[2] && av[1] > av[0]) {
if (v[1] < 0)
axis = 3;
else
axis = 2;
} else {
if (v[2] < 0)
axis = 5;
else
axis = 4;
}
// project new texture coords
for (i=0 ; i<nump ; i++, vecs+=3) {
j = vec_to_st[axis][2];
if (j > 0)
dv = vecs[j - 1];
else
dv = -vecs[-j - 1];
j = vec_to_st[axis][0];
if (j < 0)
s = -vecs[-j -1] / dv;
else
s = vecs[j-1] / dv;
j = vec_to_st[axis][1];
if (j < 0)
t = -vecs[-j -1] / dv;
else
t = vecs[j-1] / dv;
if (s < skymins[0][axis])
skymins[0][axis] = s;
if (t < skymins[1][axis])
skymins[1][axis] = t;
if (s > skymaxs[0][axis])
skymaxs[0][axis] = s;
if (t > skymaxs[1][axis])
skymaxs[1][axis] = t;
}
}
#define MAX_CLIP_VERTS 64
void
ClipSkyPolygon (int nump, vec3_t vecs, int stage) {
float *norm;
float *v;
qboolean front, back;
float d, e;
float dists[MAX_CLIP_VERTS];
int sides[MAX_CLIP_VERTS];
vec3_t newv[2][MAX_CLIP_VERTS];
int newc[2];
int i, j;
if (nump > MAX_CLIP_VERTS-2)
Sys_Error ("ClipSkyPolygon: MAX_CLIP_VERTS");
if (stage == 6) { // fully clipped, so draw it
DrawSkyPolygon (nump, vecs);
return;
}
front = back = false;
norm = skyclip[stage];
for (i=0, v = vecs ; i<nump ; i++, v+=3) {
d = DotProduct (v, norm);
if (d > ON_EPSILON) {
front = true;
sides[i] = SIDE_FRONT;
} else if (d < ON_EPSILON) {
back = true;
sides[i] = SIDE_BACK;
} else
sides[i] = SIDE_ON;
dists[i] = d;
}
if (!front || !back) { // not clipped
ClipSkyPolygon (nump, vecs, stage+1);
return;
}
// clip it
sides[i] = sides[0];
dists[i] = dists[0];
VectorCopy (vecs, (vecs+(i*3)) );
newc[0] = newc[1] = 0;
for (i=0, v = vecs ; i<nump ; i++, v+=3) {
switch (sides[i]) {
case SIDE_FRONT:
VectorCopy (v, newv[0][newc[0]]);
newc[0]++;
break;
case SIDE_BACK:
VectorCopy (v, newv[1][newc[1]]);
newc[1]++;
break;
case SIDE_ON:
VectorCopy (v, newv[0][newc[0]]);
newc[0]++;
VectorCopy (v, newv[1][newc[1]]);
newc[1]++;
break;
}
if (sides[i] == SIDE_ON || sides[i+1] == SIDE_ON || sides[i+1] == sides[i])
continue;
d = dists[i] / (dists[i] - dists[i+1]);
for (j=0 ; j<3 ; j++) {
e = v[j] + d*(v[j+3] - v[j]);
newv[0][newc[0]][j] = e;
newv[1][newc[1]][j] = e;
}
newc[0]++;
newc[1]++;
}
// continue
ClipSkyPolygon (newc[0], newv[0][0], stage+1);
ClipSkyPolygon (newc[1], newv[1][0], stage+1);
}
/*
R_DrawSkyChain
*/
void
R_DrawSkyChain (msurface_t *s) {
msurface_t *fa;
int i;
vec3_t verts[MAX_CLIP_VERTS];
glpoly_t *p;
if (r_sky->value)
{
c_sky = 0;
GL_Bind(solidskytexture);
// calculate vertex values for sky box
for (fa=s ; fa ; fa=fa->texturechain) {
for (p=fa->polys ; p ; p=p->next) {
for (i=0 ; i<p->numverts ; i++) {
VectorSubtract (p->verts[i], r_origin, verts[i]);
}
ClipSkyPolygon (p->numverts, verts[0], 0);
}
}
}
else
{
GL_DisableMultitexture();
// used when gl_texsort is on
GL_Bind(solidskytexture);
speedscale = realtime*8;
speedscale -= (int)speedscale & ~127 ;
for (fa=s ; fa ; fa=fa->texturechain)
EmitSkyPolys (fa);
glEnable (GL_BLEND);
GL_Bind (alphaskytexture);
speedscale = realtime*16;
speedscale -= (int)speedscale & ~127 ;
for (fa=s ; fa ; fa=fa->texturechain)
EmitSkyPolys (fa);
glDisable (GL_BLEND);
}
}
/*
R_ClearSkyBox
*/
void
R_ClearSkyBox (void) {
int i;
for (i=0 ; i<6 ; i++) {
skymins[0][i] = skymins[1][i] = 9999;
skymaxs[0][i] = skymaxs[1][i] = -9999;
}
}
void
MakeSkyVec (float s, float t, int axis) {
vec3_t v, b;
int j, k;
b[0] = s*2048;
b[1] = t*2048;
b[2] = 2048;
for (j=0 ; j<3 ; j++) {
k = st_to_vec[axis][j];
if (k < 0)
v[j] = -b[-k - 1];
else
v[j] = b[k - 1];
v[j] += r_origin[j];
}
// avoid bilerp seam
s = (s+1)*0.5;
t = (t+1)*0.5;
if (s < 1.0/512)
s = 1.0/512;
else if (s > 511.0/512)
s = 511.0/512;
if (t < 1.0/512)
t = 1.0/512;
else if (t > 511.0/512)
t = 511.0/512;
t = 1.0 - t;
glTexCoord2f (s, t);
glVertex3fv (v);
}
/*
R_DrawSkyBox
*/
int skytexorder[6] = {0,2,1,3,4,5};
void
R_DrawSkyBox (void) {
int i;
#if 0
glEnable (GL_BLEND);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glColor4f (1,1,1,0.5);
glDisable (GL_DEPTH_TEST);
#endif
for (i=0 ; i<6 ; i++)
{
if (skymins[0][i] >= skymaxs[0][i]
|| skymins[1][i] >= skymaxs[1][i])
continue;
GL_Bind (SKY_TEX+skytexorder[i]);
#if 0
skymins[0][i] = -1;
skymins[1][i] = -1;
skymaxs[0][i] = 1;
skymaxs[1][i] = 1;
#endif
glBegin (GL_QUADS);
MakeSkyVec (skymins[0][i], skymins[1][i], i);
MakeSkyVec (skymins[0][i], skymaxs[1][i], i);
MakeSkyVec (skymaxs[0][i], skymaxs[1][i], i);
MakeSkyVec (skymaxs[0][i], skymins[1][i], i);
glEnd ();
}
#if 0
glDisable (GL_BLEND);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glColor4f (1,1,1,0.5);
glEnable (GL_DEPTH_TEST);
#endif
}
/*
R_InitSky
A sky texture is 256*128, with the right side being a masked overlay
*/
void
R_InitSky (texture_t *mt) {
int i, j, p;
byte *src;
unsigned trans[128*128];
unsigned transpix;
int r, g, b;
unsigned *rgba;
src = (byte *)mt + mt->offsets[0];
// make an average value for the back to avoid
// a fringe on the top level
r = g = b = 0;
for (i=0 ; i<128 ; i++) {
for (j=0 ; j<128 ; j++) {
p = src[i*256 + j + 128];
rgba = &d_8to24table[p];
trans[(i*128) + j] = *rgba;
r += ((byte *)rgba)[0];
g += ((byte *)rgba)[1];
b += ((byte *)rgba)[2];
}
}
((byte *)&transpix)[0] = r/(128*128);
((byte *)&transpix)[1] = g/(128*128);
((byte *)&transpix)[2] = b/(128*128);
((byte *)&transpix)[3] = 0;
if (!solidskytexture)
solidskytexture = texture_extension_number++;
GL_Bind (solidskytexture );
glTexImage2D (GL_TEXTURE_2D, 0, gl_solid_format, 128, 128, 0, GL_RGBA, GL_UNSIGNED_BYTE, trans);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
for (i=0 ; i<128 ; i++) {
for (j=0 ; j<128 ; j++) {
p = src[i*256 + j];
if (p == 0)
trans[(i*128) + j] = transpix;
else
trans[(i*128) + j] = d_8to24table[p];
}
}
if ( !alphaskytexture )
alphaskytexture = texture_extension_number++;
GL_Bind(alphaskytexture);
glTexImage2D (GL_TEXTURE_2D, 0, gl_alpha_format, 128, 128, 0, GL_RGBA, GL_UNSIGNED_BYTE, trans);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}
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