newtree/source/gl_warp.c
Joseph Carter 1a72e3ad83 LordHavoc's skydome/skybox ...
Much better for clearing the screen and stuff, will get used more later
on.  For now it just makes the sky's edge off in the distance and makes
the non-skybox sky more of a dome than a box with rounded off edges.

Visual bug: drawing everything this way leaves blending off, particles end
up being solid tris.  All I gotta do is turn blend back on, no biggie.

Visual bug: skydome being in the distance creates the same see through
walls effect that skyboxes have.  Not a problem since I know where to fix
that.

There's tons of dead code in here still, I'm probably going to move the
sky stuff into gl_sky.c and clean up LordHavoc's code a bit, I can do
the skybox at least cheaper than he does.  We'll see about the dome.
2000-06-11 11:12:27 +00:00

1236 lines
24 KiB
C

/*
gl_warp.c
sky and water polygons
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
$Id$
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <string.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#ifdef HAVE_STRINGS_H
#include <strings.h>
#endif
#include "bothdefs.h"
#include "console.h"
#include "model.h"
#include "glquake.h"
#include "sys.h"
extern double realtime;
extern model_t *loadmodel;
extern int skytexturenum;
int solidskytexture;
int alphaskytexture;
float speedscale; // for top sky and bottom sky
// Set to true if a valid skybox is loaded --KB
qboolean skyloaded = false;
msurface_t *warpface;
extern cvar_t *gl_subdivide_size;
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
Breaks 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.h"
};
#define TURBSCALE (256.0 / (2 * M_PI))
/*
=============
EmitWaterPolys
Does 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;
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);
glVertex3fv (v);
}
glEnd ();
}
}
#if 0
/*
=============
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
Does 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();
glBindTexture (GL_TEXTURE_2D, solidskytexture);
speedscale = realtime*8;
speedscale -= (int)speedscale & ~127 ;
EmitSkyPolys (fa);
glBindTexture (GL_TEXTURE_2D, alphaskytexture);
speedscale = realtime*16;
speedscale -= (int)speedscale & ~127 ;
EmitSkyPolys (fa);
}
#endif
/*
=================================================================
Quake 2 environment sky
=================================================================
*/
#define SKY_TEX 2000
/*
=================================================================
PCX Loading
=================================================================
*/
byte *pcx_rgb;
/*
============
LoadPCX
============
*/
void LoadPCX (FILE *f)
{
pcx_t *pcx, pcxbuf;
byte palette[768];
byte *pix;
int x, y;
int dataByte, runLength;
int count;
//
// parse the PCX file
//
fread (&pcxbuf, 1, sizeof(pcxbuf), f);
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
fseek (f, -768, SEEK_END);
fread (palette, 1, 768, f);
fseek (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 = fgetc(f);
if((dataByte & 0xC0) == 0xC0)
{
runLength = dataByte & 0x3F;
dataByte = fgetc(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++;
}
}
}
}
/*
=========================================================
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;
TargaHeader targa_header;
byte *targa_rgba;
int fgetLittleShort (FILE *f)
{
byte b1, b2;
b1 = fgetc(f);
b2 = fgetc(f);
return (short)(b1 + b2*256);
}
int fgetLittleLong (FILE *f)
{
byte b1, b2, b3, b4;
b1 = fgetc(f);
b2 = fgetc(f);
b3 = fgetc(f);
b4 = fgetc(f);
return b1 + (b2<<8) + (b3<<16) + (b4<<24);
}
/*
=============
LoadTGA
=============
*/
void LoadTGA (FILE *fin)
{
int columns, rows, numPixels;
byte *pixbuf;
int row, column;
unsigned char red = 0, green = 0, blue = 0, alphabyte = 0;
targa_header.id_length = fgetc(fin);
targa_header.colormap_type = fgetc(fin);
targa_header.image_type = fgetc(fin);
targa_header.colormap_index = fgetLittleShort(fin);
targa_header.colormap_length = fgetLittleShort(fin);
targa_header.colormap_size = fgetc(fin);
targa_header.x_origin = fgetLittleShort(fin);
targa_header.y_origin = fgetLittleShort(fin);
targa_header.width = fgetLittleShort(fin);
targa_header.height = fgetLittleShort(fin);
targa_header.pixel_size = fgetc(fin);
targa_header.attributes = fgetc(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)
fseek(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 = getc(fin);
green = getc(fin);
red = getc(fin);
*pixbuf++ = red;
*pixbuf++ = green;
*pixbuf++ = blue;
*pixbuf++ = 255;
break;
case 32:
blue = getc(fin);
green = getc(fin);
red = getc(fin);
alphabyte = getc(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=getc(fin);
packetSize = 1 + (packetHeader & 0x7f);
if (packetHeader & 0x80) { // run-length packet
switch (targa_header.pixel_size) {
case 24:
blue = getc(fin);
green = getc(fin);
red = getc(fin);
alphabyte = 255;
break;
case 32:
blue = getc(fin);
green = getc(fin);
red = getc(fin);
alphabyte = getc(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 = getc(fin);
green = getc(fin);
red = getc(fin);
*pixbuf++ = red;
*pixbuf++ = green;
*pixbuf++ = blue;
*pixbuf++ = 255;
break;
case 32:
blue = getc(fin);
green = getc(fin);
red = getc(fin);
alphabyte = getc(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:;
}
}
fclose(fin);
}
/*
==================
R_LoadSkys
==================
*/
char *suf[6] = {"rt", "bk", "lf", "ft", "up", "dn"};
void R_LoadSkys (char * skyname)
{
int i;
FILE *f;
char name[64];
if (stricmp (skyname, "none") == 0)
{
skyloaded = false;
return;
}
skyloaded = true;
for (i=0 ; i<6 ; i++)
{
glBindTexture (GL_TEXTURE_2D, SKY_TEX + i);
snprintf (name, sizeof(name),"env/%s%s.tga", skyname, suf[i]);
COM_FOpenFile (name, &f);
if (!f)
{
Con_DPrintf ("Couldn't load %s\n", name);
skyloaded = false;
continue;
}
LoadTGA (f);
glTexImage2D (GL_TEXTURE_2D, 0, gl_solid_format, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, targa_rgba);
free (targa_rgba);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}
if (!skyloaded)
Con_Printf ("Unable to load skybox %s, using normal sky\n",
skyname);
}
void
R_SkyBoxPolyVec(float s, float t, float x, float y, float z)
{
// avoid interpolation seams
s = s * (254.0/256.0) + (1.0/256.0);
t = t * (254.0/256.0) + (1.0/256.0);
glTexCoord2f(s, t);
glVertex3f(r_refdef.vieworg[0] + x * 1024,
r_refdef.vieworg[1] + y * 1024,
r_refdef.vieworg[2] + z * 1024);
}
void R_SkyBox()
{
GL_DisableMultitexture();
glEnable (GL_DEPTH_TEST);
glDepthFunc (GL_ALWAYS);
glDisable (GL_BLEND);
glTexEnvf (GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glDepthRange ((gldepthmax-gldepthmin)*0.95+gldepthmin, gldepthmax);
glColor3f (0.5, 0.5, 0.5);
// front
glBindTexture(GL_TEXTURE_2D, SKY_TEX + 3);
glBegin(GL_QUADS);
R_SkyBoxPolyVec(1, 0, 1, -1, 1);
R_SkyBoxPolyVec(1, 1, 1, -1, -1);
R_SkyBoxPolyVec(0, 1, 1, 1, -1);
R_SkyBoxPolyVec(0, 0, 1, 1, 1);
glEnd();
// back
glBindTexture(GL_TEXTURE_2D, SKY_TEX + 1);
glBegin(GL_QUADS);
R_SkyBoxPolyVec(1, 0, -1, 1, 1);
R_SkyBoxPolyVec(1, 1, -1, 1, -1);
R_SkyBoxPolyVec(0, 1, -1, -1, -1);
R_SkyBoxPolyVec(0, 0, -1, -1, 1);
glEnd();
// right
glBindTexture(GL_TEXTURE_2D, SKY_TEX + 0);
glBegin(GL_QUADS);
R_SkyBoxPolyVec(1, 0, 1, 1, 1);
R_SkyBoxPolyVec(1, 1, 1, 1, -1);
R_SkyBoxPolyVec(0, 1, -1, 1, -1);
R_SkyBoxPolyVec(0, 0, -1, 1, 1);
glEnd();
// left
glBindTexture(GL_TEXTURE_2D, SKY_TEX + 2);
glBegin(GL_QUADS);
R_SkyBoxPolyVec(1, 0, -1, -1, 1);
R_SkyBoxPolyVec(1, 1, -1, -1, -1);
R_SkyBoxPolyVec(0, 1, 1, -1, -1);
R_SkyBoxPolyVec(0, 0, 1, -1, 1);
glEnd();
// top
glBindTexture(GL_TEXTURE_2D, SKY_TEX + 4);
glBegin(GL_QUADS);
R_SkyBoxPolyVec(1, 0, 1, -1, 1);
R_SkyBoxPolyVec(1, 1, 1, 1, 1);
R_SkyBoxPolyVec(0, 1, -1, 1, 1);
R_SkyBoxPolyVec(0, 0, -1, -1, 1);
glEnd();
// bottom
glBindTexture(GL_TEXTURE_2D, SKY_TEX + 5);
glBegin(GL_QUADS);
R_SkyBoxPolyVec(1, 0, 1, 1, -1);
R_SkyBoxPolyVec(1, 1, 1, -1, -1);
R_SkyBoxPolyVec(0, 1, -1, -1, -1);
R_SkyBoxPolyVec(0, 0, -1, 1, -1);
glEnd();
glColor3f (1,1,1);
glDepthFunc (GL_LEQUAL);
glEnable (GL_DEPTH_TEST);
glDepthRange(gldepthmin, gldepthmax);
}
vec3_t domescale;
void
skydome(float s)
{
float a, b, x, y, a1x, a1y, a2x, a2y;
vec3_t v;
for (a = 0; a < 1; a += (1.0 / 32.0))
{
a1x = cos(a * M_PI * 2);
a1y = -sin(a * M_PI * 2);
a2x = cos((a+(1.0/32.0)) * M_PI * 2);
a2y = -sin((a+(1.0/32.0)) * M_PI * 2);
glBegin (GL_TRIANGLE_STRIP);
for (b = 0; b <= 1; b += (1.0 / 32.0))
{
x = cos(b * M_PI * 2);
y = -sin(b * M_PI * 2);
v[0] = a1x*x * domescale[0];
v[1] = a1y*x * domescale[1];
v[2] = y * domescale[2];
glTexCoord2f((v[0] + s) * (1.0 / 128.0),
(v[1] + s) * (1.0 / 128.0));
glVertex3f(v[0] + r_refdef.vieworg[0],
v[1] + r_refdef.vieworg[1],
v[2] + r_refdef.vieworg[2]);
v[0] = a2x*x * domescale[0];
v[1] = a2y*x * domescale[1];
v[2] = y * domescale[2];
glTexCoord2f((v[0] + s) * (1.0 / 128.0),
(v[1] + s) * (1.0 / 128.0));
glVertex3f(v[0] + r_refdef.vieworg[0],
v[1] + r_refdef.vieworg[1],
v[2] + r_refdef.vieworg[2]);
}
glEnd ();
}
}
void
R_SkyDome()
{
GL_DisableMultitexture();
glEnable (GL_DEPTH_TEST);
glDepthFunc (GL_ALWAYS);
glDisable (GL_BLEND);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glDepthRange((gldepthmax-gldepthmin)*0.95+gldepthmin,gldepthmax);
glColor3f(0.5,0.5,0.5);
// base sky
glBindTexture(GL_TEXTURE_2D, solidskytexture);
domescale[0] = 512;
domescale[1] = 512;
domescale[2] = 128;
speedscale = realtime*8;
speedscale -= (int)speedscale & ~127;
skydome(speedscale);
glEnable (GL_BLEND);
// clouds
glBindTexture(GL_TEXTURE_2D, alphaskytexture);
domescale[0] = 512;
domescale[1] = 512;
domescale[2] = 128;
speedscale = realtime*16;
speedscale -= (int)speedscale & ~127;
skydome(speedscale);
glDisable (GL_BLEND);
glColor3f (1,1,1);
glDepthFunc (GL_LEQUAL);
glEnable (GL_DEPTH_TEST);
glDepthRange(gldepthmin, gldepthmax);
}
void
R_Sky ( void )
{
if (skyloaded)
R_SkyBox();
else
R_SkyDome();
}
#if 0
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++;
// 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 (allowskybox && skyloaded)
{
c_sky = 0;
glBindTexture (GL_TEXTURE_2D, 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 {
// skies have no lightmap to prevent overbrighting --KB
glColor3f (0.5, 0.5, 0.5);
GL_DisableMultitexture();
// used when gl_texsort is on
glBindTexture (GL_TEXTURE_2D, solidskytexture);
speedscale = realtime*8;
speedscale -= (int)speedscale & ~127 ;
for (fa=s ; fa ; fa=fa->texturechain)
EmitSkyPolys (fa);
glBindTexture (GL_TEXTURE_2D, alphaskytexture);
speedscale = realtime*16;
speedscale -= (int)speedscale & ~127 ;
for (fa=s ; fa ; fa=fa->texturechain)
EmitSkyPolys (fa);
// the rest of the texture chain does though --KB
glColor3f (1.0, 1.0, 1.0);
}
}
/*
==============
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;
for (i=0 ; i<6 ; i++)
{
if (skymins[0][i] >= skymaxs[0][i]
|| skymins[1][i] >= skymaxs[1][i])
continue;
glBindTexture (GL_TEXTURE_2D, SKY_TEX+skytexorder[i]);
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 ();
}
}
#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++;
glBindTexture (GL_TEXTURE_2D, 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++;
glBindTexture (GL_TEXTURE_2D, 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);
}