cnq3/code/renderer/tr_sky.cpp
myT c60d47e93f cleaned up tr_gl2.cpp and prefixes in win32 code
tr_gl2.cpp now uses the proper interface for printing errors
tr_gl2.cpp now has function names that make sense
removed old references to GLimp_*
cleaned up prefixes in the Windows platform layer
2017-11-03 19:35:35 +01:00

597 lines
15 KiB
C++

/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.
This file is part of Quake III Arena source code.
Quake III Arena source code 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.
Quake III Arena source code 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 Quake III Arena source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
===========================================================================
*/
// tr_sky.c
#include "tr_local.h"
#define SKY_SUBDIVISIONS 8
#define HALF_SKY_SUBDIVISIONS (SKY_SUBDIVISIONS/2)
static float s_cloudTexCoords[6][SKY_SUBDIVISIONS+1][SKY_SUBDIVISIONS+1][2];
/*
===================================================================================
POLYGON TO BOX SIDE PROJECTION
===================================================================================
*/
static vec2_t sky_mins_st[6], sky_maxs_st[6];
/*
================
AddSkyPolygon
================
*/
static void AddSkyPolygon (int nump, vec3_t vecs)
{
int i,j;
vec3_t v, av;
float s, t, dv;
int axis;
float *vp;
// s = [0]/[2], t = [1]/[2]
static 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}
};
// 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];
if (dv < 0.001f)
continue; // don't divide by zero
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 (sky_mins_st[axis][0] > s)
sky_mins_st[axis][0] = s;
if (sky_mins_st[axis][1] > t)
sky_mins_st[axis][1] = t;
if (sky_maxs_st[axis][0] < s)
sky_maxs_st[axis][0] = s;
if (sky_maxs_st[axis][1] < t)
sky_maxs_st[axis][1] = t;
}
}
#define ON_EPSILON 0.1f // point on plane side epsilon
#define MAX_CLIP_VERTS 64
static const vec3_t sky_clip[6] =
{
{ 1, 1, 0 }, // R
{ 1, -1, 0 }, // L
{ 0, -1, 1 }, // B
{ 0, 1, 1 }, // F
{ 1, 0, 1 }, // U
{ -1, 0, 1 } // D
};
static void ClipSkyPolygon (int nump, vec3_t vecs, int stage)
{
const float* norm;
float *v;
qbool 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)
ri.Error (ERR_DROP, "ClipSkyPolygon: MAX_CLIP_VERTS");
if (stage == 6)
{ // fully clipped, so draw it
AddSkyPolygon (nump, vecs);
return;
}
front = back = qfalse;
norm = sky_clip[stage];
for (i=0, v = vecs ; i<nump ; i++, v+=3)
{
d = DotProduct (v, norm);
if (d > ON_EPSILON)
{
front = qtrue;
sides[i] = SIDE_FRONT;
}
else if (d < -ON_EPSILON)
{
back = qtrue;
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);
}
static void ClearSkyBox()
{
for (int i = 0; i < 6; ++i) {
sky_mins_st[i][0] = sky_mins_st[i][1] = 9999;
sky_maxs_st[i][0] = sky_maxs_st[i][1] = -9999;
}
}
static void RB_ClipSkyPolygons( const shaderCommands_t* input )
{
vec3_t p[4]; // need one extra point for clipping
ClearSkyBox();
for ( int i = 0; i < input->numIndexes; i += 3 ) {
VectorSubtract( input->xyz[input->indexes[i+0]], backEnd.viewParms.orient.origin, p[0] );
VectorSubtract( input->xyz[input->indexes[i+1]], backEnd.viewParms.orient.origin, p[1] );
VectorSubtract( input->xyz[input->indexes[i+2]], backEnd.viewParms.orient.origin, p[2] );
ClipSkyPolygon( 3, p[0], 0 );
}
}
/*
===================================================================================
CLOUD VERTEX GENERATION
===================================================================================
*/
static vec3_t s_skyPoints[SKY_SUBDIVISIONS+1][SKY_SUBDIVISIONS+1];
static vec2_t s_skyTexCoords[SKY_SUBDIVISIONS+1][SKY_SUBDIVISIONS+1];
// s, t range from -1 to 1
static void MakeSkyVec( float s, float t, int axis, vec2_t st, vec3_t xyz )
{
// 1 = s, 2 = t, 3 = zfar
static const 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
};
vec3_t b;
float boxSize = backEnd.viewParms.zFar / 1.75; // div sqrt(3)
b[0] = boxSize * s;
b[1] = boxSize * t;
b[2] = boxSize;
for (int i = 0; i < 3; ++i) {
int k = st_to_vec[axis][i];
xyz[i] = (k < 0) ? -b[-k - 1] : b[k - 1];
}
// convert our -1:1 range (and inverted t) into GL TCs
if ( st ) {
st[0] = Com_Clamp( 0, 1, (s+1) * 0.5 );
st[1] = 1.0 - Com_Clamp( 0, 1, (t+1) * 0.5 );
}
}
static void CalcSkyBounds()
{
for (int i = 0; i < 6; ++i) {
sky_mins_st[i][0] = floor( sky_mins_st[i][0] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
sky_mins_st[i][1] = floor( sky_mins_st[i][1] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
sky_maxs_st[i][0] = ceil( sky_maxs_st[i][0] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
sky_maxs_st[i][1] = ceil( sky_maxs_st[i][1] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
}
}
static void DrawSkySide( const image_t* image, const int mins[2], const int maxs[2] )
{
int s, t;
GL_Bind( image );
for ( t = mins[1]+HALF_SKY_SUBDIVISIONS; t < maxs[1]+HALF_SKY_SUBDIVISIONS; t++ )
{
qglBegin( GL_TRIANGLE_STRIP );
for ( s = mins[0]+HALF_SKY_SUBDIVISIONS; s <= maxs[0]+HALF_SKY_SUBDIVISIONS; s++ )
{
qglTexCoord2fv( s_skyTexCoords[t][s] );
qglVertex3fv( s_skyPoints[t][s] );
qglTexCoord2fv( s_skyTexCoords[t+1][s] );
qglVertex3fv( s_skyPoints[t+1][s] );
}
qglEnd();
}
}
static void DrawSkyBox( const shader_t* shader )
{
// Com_Memset( s_skyTexCoords, 0, sizeof( s_skyTexCoords ) );
for (int i = 0; i < 6; ++i)
{
int sky_mins_subd[2], sky_maxs_subd[2];
if ( ( sky_mins_st[i][0] >= sky_maxs_st[i][0] ) || ( sky_mins_st[i][1] >= sky_maxs_st[i][1] ) ) {
continue;
}
sky_mins_subd[0] = HALF_SKY_SUBDIVISIONS * Com_Clamp( -1, 1, sky_mins_st[i][0] );
sky_mins_subd[1] = HALF_SKY_SUBDIVISIONS * Com_Clamp( -1, 1, sky_mins_st[i][1] );
sky_maxs_subd[0] = HALF_SKY_SUBDIVISIONS * Com_Clamp( -1, 1, sky_maxs_st[i][0] );
sky_maxs_subd[1] = HALF_SKY_SUBDIVISIONS * Com_Clamp( -1, 1, sky_maxs_st[i][1] );
//
// iterate through the subdivisions
//
for (int t = sky_mins_subd[1]+HALF_SKY_SUBDIVISIONS; t <= sky_maxs_subd[1]+HALF_SKY_SUBDIVISIONS; ++t)
{
for (int s = sky_mins_subd[0]+HALF_SKY_SUBDIVISIONS; s <= sky_maxs_subd[0]+HALF_SKY_SUBDIVISIONS; ++s)
{
MakeSkyVec( ( s - HALF_SKY_SUBDIVISIONS ) / ( float ) HALF_SKY_SUBDIVISIONS,
( t - HALF_SKY_SUBDIVISIONS ) / ( float ) HALF_SKY_SUBDIVISIONS,
i, s_skyTexCoords[t][s], s_skyPoints[t][s] );
}
}
DrawSkySide( shader->sky.outerbox[i], sky_mins_subd, sky_maxs_subd );
}
}
static void FillCloudySkySide( const int mins[2], const int maxs[2], qbool addIndexes )
{
int s, t;
int vertexStart = tess.numVertexes;
for ( t = mins[1]+HALF_SKY_SUBDIVISIONS; t <= maxs[1]+HALF_SKY_SUBDIVISIONS; t++ )
{
for ( s = mins[0]+HALF_SKY_SUBDIVISIONS; s <= maxs[0]+HALF_SKY_SUBDIVISIONS; s++ )
{
VectorAdd( s_skyPoints[t][s], backEnd.viewParms.orient.origin, tess.xyz[tess.numVertexes] );
tess.texCoords[tess.numVertexes][0][0] = s_skyTexCoords[t][s][0];
tess.texCoords[tess.numVertexes][0][1] = s_skyTexCoords[t][s][1];
tess.numVertexes++;
if ( tess.numVertexes >= SHADER_MAX_VERTEXES )
{
ri.Error( ERR_DROP, "SHADER_MAX_VERTEXES hit in FillCloudySkySide()\n" );
}
}
}
// only add indexes for one pass, otherwise it would draw multiple times for each pass
if ( !addIndexes )
return;
int tHeight = maxs[1] - mins[1] + 1;
int sWidth = maxs[0] - mins[0] + 1;
for ( t = 0; t < tHeight-1; t++ )
{
for ( s = 0; s < sWidth-1; s++ )
{
tess.indexes[tess.numIndexes] = vertexStart + s + t * ( sWidth );
tess.numIndexes++;
tess.indexes[tess.numIndexes] = vertexStart + s + ( t + 1 ) * ( sWidth );
tess.numIndexes++;
tess.indexes[tess.numIndexes] = vertexStart + s + 1 + t * ( sWidth );
tess.numIndexes++;
tess.indexes[tess.numIndexes] = vertexStart + s + ( t + 1 ) * ( sWidth );
tess.numIndexes++;
tess.indexes[tess.numIndexes] = vertexStart + s + 1 + ( t + 1 ) * ( sWidth );
tess.numIndexes++;
tess.indexes[tess.numIndexes] = vertexStart + s + 1 + t * ( sWidth );
tess.numIndexes++;
}
}
}
static void FillCloudBox( const shader_t* shader, int stage )
{
// skybox surfs are ordered RLBFUD, so don't draw clouds on the last one
for (int i = 0; i < 5; ++i)
{
int s, t;
int sky_mins_subd[2], sky_maxs_subd[2];
if ( ( sky_mins_st[i][0] >= sky_maxs_st[i][0] ) || ( sky_mins_st[i][1] >= sky_maxs_st[i][1] ) ) {
//ri.Printf( PRINT_ALL, "clipped cloudside %i\n", i );
continue;
}
sky_mins_subd[0] = HALF_SKY_SUBDIVISIONS * Com_Clamp( -1, 1, sky_mins_st[i][0] );
sky_mins_subd[1] = HALF_SKY_SUBDIVISIONS * Com_Clamp( -1, 1, sky_mins_st[i][1] );
sky_maxs_subd[0] = HALF_SKY_SUBDIVISIONS * Com_Clamp( -1, 1, sky_maxs_st[i][0] );
sky_maxs_subd[1] = HALF_SKY_SUBDIVISIONS * Com_Clamp( -1, 1, sky_maxs_st[i][1] );
//
// iterate through the subdivisions
//
for ( t = sky_mins_subd[1]+HALF_SKY_SUBDIVISIONS; t <= sky_maxs_subd[1]+HALF_SKY_SUBDIVISIONS; t++ )
{
for ( s = sky_mins_subd[0]+HALF_SKY_SUBDIVISIONS; s <= sky_maxs_subd[0]+HALF_SKY_SUBDIVISIONS; s++ )
{
MakeSkyVec( ( s - HALF_SKY_SUBDIVISIONS ) / ( float ) HALF_SKY_SUBDIVISIONS,
( t - HALF_SKY_SUBDIVISIONS ) / ( float ) HALF_SKY_SUBDIVISIONS,
i,
NULL,
s_skyPoints[t][s] );
s_skyTexCoords[t][s][0] = s_cloudTexCoords[i][t][s][0];
s_skyTexCoords[t][s][1] = s_cloudTexCoords[i][t][s][1];
}
}
// only add indexes for first stage
FillCloudySkySide( sky_mins_subd, sky_maxs_subd, (qbool)(stage == 0) );
}
}
static void R_BuildCloudData( shaderCommands_t* input )
{
assert( input->shader->sort == SS_ENVIRONMENT );
// set up for drawing
tess.numIndexes = 0;
tess.numVertexes = 0;
if (!input->shader->sky.cloudHeight)
return;
for (int i = 0; (i < MAX_SHADER_STAGES) && tess.xstages[i]; ++i) {
FillCloudBox( input->shader, i );
}
}
// called when a sky shader is parsed
void R_InitSkyTexCoords( float heightCloud )
{
int i, s, t;
float radiusWorld = 4096;
float p;
float sRad, tRad;
vec3_t skyVec;
vec3_t v;
// init zfar so MakeSkyVec works even though
// a world hasn't been bounded
backEnd.viewParms.zFar = 1024;
for ( i = 0; i < 6; i++ )
{
for ( t = 0; t <= SKY_SUBDIVISIONS; t++ )
{
for ( s = 0; s <= SKY_SUBDIVISIONS; s++ )
{
// compute vector from view origin to sky side integral point
MakeSkyVec(
(float)(s - HALF_SKY_SUBDIVISIONS) / HALF_SKY_SUBDIVISIONS,
(float)(t - HALF_SKY_SUBDIVISIONS) / HALF_SKY_SUBDIVISIONS,
i, NULL, skyVec
);
// compute parametric value 'p' that intersects with cloud layer
p = ( 1.0f / ( 2 * DotProduct( skyVec, skyVec ) ) ) *
( -2 * skyVec[2] * radiusWorld +
2 * sqrt( Square( skyVec[2] ) * Square( radiusWorld ) +
2 * Square( skyVec[0] ) * radiusWorld * heightCloud +
Square( skyVec[0] ) * Square( heightCloud ) +
2 * Square( skyVec[1] ) * radiusWorld * heightCloud +
Square( skyVec[1] ) * Square( heightCloud ) +
2 * Square( skyVec[2] ) * radiusWorld * heightCloud +
Square( skyVec[2] ) * Square( heightCloud ) ) );
// compute intersection point based on p
VectorScale( skyVec, p, v );
v[2] += radiusWorld;
// compute vector from world origin to intersection point 'v'
VectorNormalize( v );
sRad = Q_acos( v[0] );
tRad = Q_acos( v[1] );
s_cloudTexCoords[i][t][s][0] = sRad;
s_cloudTexCoords[i][t][s][1] = tRad;
}
}
}
}
///////////////////////////////////////////////////////////////
// all of the visible sky triangles are in tess
// other things could be stuck in here, like birds in the sky, etc
void RB_StageIteratorSky()
{
if ( r_fastsky->integer ) {
return;
}
GL_Program();
// project all the polygons onto the sky box
// to see which blocks on each side need to be drawn
RB_ClipSkyPolygons( &tess );
CalcSkyBounds();
// r_showsky will let all the sky blocks be drawn in
// front of everything to allow developers to see how
// much sky is getting sucked in
if ( r_showsky->integer ) {
qglDepthRange( 0.0, 0.0 );
} else {
qglDepthRange( 1.0, 1.0 );
}
// draw the outer skybox
if ( tess.shader->sky.outerbox[0] && tess.shader->sky.outerbox[0] != tr.defaultImage ) {
qglColor3f( tr.identityLight, tr.identityLight, tr.identityLight );
qglPushMatrix();
GL_State( 0 );
qglTranslatef (backEnd.viewParms.orient.origin[0], backEnd.viewParms.orient.origin[1], backEnd.viewParms.orient.origin[2]);
DrawSkyBox( tess.shader );
qglPopMatrix();
}
// generate the vertexes for all the clouds (if any)
// which will be drawn by the generic shader routine
R_BuildCloudData( &tess );
if (tess.numVertexes)
GL2_StageIterator();
// back to normal depth range
qglDepthRange( 0.0, 1.0 );
}