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-rwxr-xr-xcode/renderer/tr_sky.c845
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diff --git a/code/renderer/tr_sky.c b/code/renderer/tr_sky.c
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--- /dev/null
+++ b/code/renderer/tr_sky.c
@@ -0,0 +1,845 @@
+/*
+===========================================================================
+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 Foobar; 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];
+static float s_cloudTexP[6][SKY_SUBDIVISIONS+1][SKY_SUBDIVISIONS+1];
+
+/*
+===================================================================================
+
+POLYGON TO BOX SIDE PROJECTION
+
+===================================================================================
+*/
+
+static vec3_t sky_clip[6] =
+{
+ {1,1,0},
+ {1,-1,0},
+ {0,-1,1},
+ {0,1,1},
+ {1,0,1},
+ {-1,0,1}
+};
+
+static float sky_mins[2][6], sky_maxs[2][6];
+static float sky_min, sky_max;
+
+/*
+================
+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 < 0.001)
+ 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 (s < sky_mins[0][axis])
+ sky_mins[0][axis] = s;
+ if (t < sky_mins[1][axis])
+ sky_mins[1][axis] = t;
+ if (s > sky_maxs[0][axis])
+ sky_maxs[0][axis] = s;
+ if (t > sky_maxs[1][axis])
+ sky_maxs[1][axis] = t;
+ }
+}
+
+#define ON_EPSILON 0.1f // point on plane side epsilon
+#define MAX_CLIP_VERTS 64
+/*
+================
+ClipSkyPolygon
+================
+*/
+static 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)
+ 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);
+}
+
+/*
+==============
+ClearSkyBox
+==============
+*/
+static void ClearSkyBox (void) {
+ int i;
+
+ for (i=0 ; i<6 ; i++) {
+ sky_mins[0][i] = sky_mins[1][i] = 9999;
+ sky_maxs[0][i] = sky_maxs[1][i] = -9999;
+ }
+}
+
+/*
+================
+RB_ClipSkyPolygons
+================
+*/
+void RB_ClipSkyPolygons( shaderCommands_t *input )
+{
+ vec3_t p[5]; // need one extra point for clipping
+ int i, j;
+
+ ClearSkyBox();
+
+ for ( i = 0; i < input->numIndexes; i += 3 )
+ {
+ for (j = 0 ; j < 3 ; j++)
+ {
+ VectorSubtract( input->xyz[input->indexes[i+j]],
+ backEnd.viewParms.or.origin,
+ p[j] );
+ }
+ ClipSkyPolygon( 3, p[0], 0 );
+ }
+}
+
+/*
+===================================================================================
+
+CLOUD VERTEX GENERATION
+
+===================================================================================
+*/
+
+/*
+** MakeSkyVec
+**
+** Parms: s, t range from -1 to 1
+*/
+static void MakeSkyVec( float s, float t, int axis, float outSt[2], vec3_t outXYZ )
+{
+ // 1 = s, 2 = t, 3 = 2048
+ static 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;
+ int j, k;
+ float boxSize;
+
+ boxSize = backEnd.viewParms.zFar / 1.75; // div sqrt(3)
+ b[0] = s*boxSize;
+ b[1] = t*boxSize;
+ b[2] = boxSize;
+
+ for (j=0 ; j<3 ; j++)
+ {
+ k = st_to_vec[axis][j];
+ if (k < 0)
+ {
+ outXYZ[j] = -b[-k - 1];
+ }
+ else
+ {
+ outXYZ[j] = b[k - 1];
+ }
+ }
+
+ // avoid bilerp seam
+ s = (s+1)*0.5;
+ t = (t+1)*0.5;
+ if (s < sky_min)
+ {
+ s = sky_min;
+ }
+ else if (s > sky_max)
+ {
+ s = sky_max;
+ }
+
+ if (t < sky_min)
+ {
+ t = sky_min;
+ }
+ else if (t > sky_max)
+ {
+ t = sky_max;
+ }
+
+ t = 1.0 - t;
+
+
+ if ( outSt )
+ {
+ outSt[0] = s;
+ outSt[1] = t;
+ }
+}
+
+static int sky_texorder[6] = {0,2,1,3,4,5};
+static vec3_t s_skyPoints[SKY_SUBDIVISIONS+1][SKY_SUBDIVISIONS+1];
+static float s_skyTexCoords[SKY_SUBDIVISIONS+1][SKY_SUBDIVISIONS+1][2];
+
+static void DrawSkySide( struct image_s *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( shader_t *shader )
+{
+ int i;
+
+ sky_min = 0;
+ sky_max = 1;
+
+ Com_Memset( s_skyTexCoords, 0, sizeof( s_skyTexCoords ) );
+
+ for (i=0 ; i<6 ; i++)
+ {
+ int sky_mins_subd[2], sky_maxs_subd[2];
+ int s, t;
+
+ sky_mins[0][i] = floor( sky_mins[0][i] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
+ sky_mins[1][i] = floor( sky_mins[1][i] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
+ sky_maxs[0][i] = ceil( sky_maxs[0][i] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
+ sky_maxs[1][i] = ceil( sky_maxs[1][i] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
+
+ if ( ( sky_mins[0][i] >= sky_maxs[0][i] ) ||
+ ( sky_mins[1][i] >= sky_maxs[1][i] ) )
+ {
+ continue;
+ }
+
+ sky_mins_subd[0] = sky_mins[0][i] * HALF_SKY_SUBDIVISIONS;
+ sky_mins_subd[1] = sky_mins[1][i] * HALF_SKY_SUBDIVISIONS;
+ sky_maxs_subd[0] = sky_maxs[0][i] * HALF_SKY_SUBDIVISIONS;
+ sky_maxs_subd[1] = sky_maxs[1][i] * HALF_SKY_SUBDIVISIONS;
+
+ if ( sky_mins_subd[0] < -HALF_SKY_SUBDIVISIONS )
+ sky_mins_subd[0] = -HALF_SKY_SUBDIVISIONS;
+ else if ( sky_mins_subd[0] > HALF_SKY_SUBDIVISIONS )
+ sky_mins_subd[0] = HALF_SKY_SUBDIVISIONS;
+ if ( sky_mins_subd[1] < -HALF_SKY_SUBDIVISIONS )
+ sky_mins_subd[1] = -HALF_SKY_SUBDIVISIONS;
+ else if ( sky_mins_subd[1] > HALF_SKY_SUBDIVISIONS )
+ sky_mins_subd[1] = HALF_SKY_SUBDIVISIONS;
+
+ if ( sky_maxs_subd[0] < -HALF_SKY_SUBDIVISIONS )
+ sky_maxs_subd[0] = -HALF_SKY_SUBDIVISIONS;
+ else if ( sky_maxs_subd[0] > HALF_SKY_SUBDIVISIONS )
+ sky_maxs_subd[0] = HALF_SKY_SUBDIVISIONS;
+ if ( sky_maxs_subd[1] < -HALF_SKY_SUBDIVISIONS )
+ sky_maxs_subd[1] = -HALF_SKY_SUBDIVISIONS;
+ else if ( sky_maxs_subd[1] > HALF_SKY_SUBDIVISIONS )
+ sky_maxs_subd[1] = HALF_SKY_SUBDIVISIONS;
+
+ //
+ // 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,
+ s_skyTexCoords[t][s],
+ s_skyPoints[t][s] );
+ }
+ }
+
+ DrawSkySide( shader->sky.outerbox[sky_texorder[i]],
+ sky_mins_subd,
+ sky_maxs_subd );
+ }
+
+}
+
+static void FillCloudySkySide( const int mins[2], const int maxs[2], qboolean addIndexes )
+{
+ int s, t;
+ int vertexStart = tess.numVertexes;
+ int tHeight, sWidth;
+
+ tHeight = maxs[1] - mins[1] + 1;
+ sWidth = maxs[0] - mins[0] + 1;
+
+ 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.or.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 ) {
+ 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 )
+{
+ int i;
+
+ for ( i =0; i < 6; i++ )
+ {
+ int sky_mins_subd[2], sky_maxs_subd[2];
+ int s, t;
+ float MIN_T;
+
+ if ( 1 ) // FIXME? shader->sky.fullClouds )
+ {
+ MIN_T = -HALF_SKY_SUBDIVISIONS;
+
+ // still don't want to draw the bottom, even if fullClouds
+ if ( i == 5 )
+ continue;
+ }
+ else
+ {
+ switch( i )
+ {
+ case 0:
+ case 1:
+ case 2:
+ case 3:
+ MIN_T = -1;
+ break;
+ case 5:
+ // don't draw clouds beneath you
+ continue;
+ case 4: // top
+ default:
+ MIN_T = -HALF_SKY_SUBDIVISIONS;
+ break;
+ }
+ }
+
+ sky_mins[0][i] = floor( sky_mins[0][i] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
+ sky_mins[1][i] = floor( sky_mins[1][i] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
+ sky_maxs[0][i] = ceil( sky_maxs[0][i] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
+ sky_maxs[1][i] = ceil( sky_maxs[1][i] * HALF_SKY_SUBDIVISIONS ) / HALF_SKY_SUBDIVISIONS;
+
+ if ( ( sky_mins[0][i] >= sky_maxs[0][i] ) ||
+ ( sky_mins[1][i] >= sky_maxs[1][i] ) )
+ {
+ continue;
+ }
+
+ sky_mins_subd[0] = myftol( sky_mins[0][i] * HALF_SKY_SUBDIVISIONS );
+ sky_mins_subd[1] = myftol( sky_mins[1][i] * HALF_SKY_SUBDIVISIONS );
+ sky_maxs_subd[0] = myftol( sky_maxs[0][i] * HALF_SKY_SUBDIVISIONS );
+ sky_maxs_subd[1] = myftol( sky_maxs[1][i] * HALF_SKY_SUBDIVISIONS );
+
+ if ( sky_mins_subd[0] < -HALF_SKY_SUBDIVISIONS )
+ sky_mins_subd[0] = -HALF_SKY_SUBDIVISIONS;
+ else if ( sky_mins_subd[0] > HALF_SKY_SUBDIVISIONS )
+ sky_mins_subd[0] = HALF_SKY_SUBDIVISIONS;
+ if ( sky_mins_subd[1] < MIN_T )
+ sky_mins_subd[1] = MIN_T;
+ else if ( sky_mins_subd[1] > HALF_SKY_SUBDIVISIONS )
+ sky_mins_subd[1] = HALF_SKY_SUBDIVISIONS;
+
+ if ( sky_maxs_subd[0] < -HALF_SKY_SUBDIVISIONS )
+ sky_maxs_subd[0] = -HALF_SKY_SUBDIVISIONS;
+ else if ( sky_maxs_subd[0] > HALF_SKY_SUBDIVISIONS )
+ sky_maxs_subd[0] = HALF_SKY_SUBDIVISIONS;
+ if ( sky_maxs_subd[1] < MIN_T )
+ sky_maxs_subd[1] = MIN_T;
+ else if ( sky_maxs_subd[1] > HALF_SKY_SUBDIVISIONS )
+ sky_maxs_subd[1] = HALF_SKY_SUBDIVISIONS;
+
+ //
+ // 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, ( stage == 0 ) );
+ }
+}
+
+/*
+** R_BuildCloudData
+*/
+void R_BuildCloudData( shaderCommands_t *input )
+{
+ int i;
+ shader_t *shader;
+
+ shader = input->shader;
+
+ assert( shader->isSky );
+
+ sky_min = 1.0 / 256.0f; // FIXME: not correct?
+ sky_max = 255.0 / 256.0f;
+
+ // set up for drawing
+ tess.numIndexes = 0;
+ tess.numVertexes = 0;
+
+ if ( input->shader->sky.cloudHeight )
+ {
+ for ( i = 0; i < MAX_SHADER_STAGES; i++ )
+ {
+ if ( !tess.xstages[i] ) {
+ break;
+ }
+ FillCloudBox( input->shader, i );
+ }
+ }
+}
+
+/*
+** R_InitSkyTexCoords
+** Called when a sky shader is parsed
+*/
+#define SQR( a ) ((a)*(a))
+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( ( s - HALF_SKY_SUBDIVISIONS ) / ( float ) HALF_SKY_SUBDIVISIONS,
+ ( t - HALF_SKY_SUBDIVISIONS ) / ( float ) 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( SQR( skyVec[2] ) * SQR( radiusWorld ) +
+ 2 * SQR( skyVec[0] ) * radiusWorld * heightCloud +
+ SQR( skyVec[0] ) * SQR( heightCloud ) +
+ 2 * SQR( skyVec[1] ) * radiusWorld * heightCloud +
+ SQR( skyVec[1] ) * SQR( heightCloud ) +
+ 2 * SQR( skyVec[2] ) * radiusWorld * heightCloud +
+ SQR( skyVec[2] ) * SQR( heightCloud ) ) );
+
+ s_cloudTexP[i][t][s] = p;
+
+ // 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;
+ }
+ }
+ }
+}
+
+//======================================================================================
+
+/*
+** RB_DrawSun
+*/
+void RB_DrawSun( void ) {
+ float size;
+ float dist;
+ vec3_t origin, vec1, vec2;
+ vec3_t temp;
+
+ if ( !backEnd.skyRenderedThisView ) {
+ return;
+ }
+ if ( !r_drawSun->integer ) {
+ return;
+ }
+ qglLoadMatrixf( backEnd.viewParms.world.modelMatrix );
+ qglTranslatef (backEnd.viewParms.or.origin[0], backEnd.viewParms.or.origin[1], backEnd.viewParms.or.origin[2]);
+
+ dist = backEnd.viewParms.zFar / 1.75; // div sqrt(3)
+ size = dist * 0.4;
+
+ VectorScale( tr.sunDirection, dist, origin );
+ PerpendicularVector( vec1, tr.sunDirection );
+ CrossProduct( tr.sunDirection, vec1, vec2 );
+
+ VectorScale( vec1, size, vec1 );
+ VectorScale( vec2, size, vec2 );
+
+ // farthest depth range
+ qglDepthRange( 1.0, 1.0 );
+
+ // FIXME: use quad stamp
+ RB_BeginSurface( tr.sunShader, tess.fogNum );
+ VectorCopy( origin, temp );
+ VectorSubtract( temp, vec1, temp );
+ VectorSubtract( temp, vec2, temp );
+ VectorCopy( temp, tess.xyz[tess.numVertexes] );
+ tess.texCoords[tess.numVertexes][0][0] = 0;
+ tess.texCoords[tess.numVertexes][0][1] = 0;
+ tess.vertexColors[tess.numVertexes][0] = 255;
+ tess.vertexColors[tess.numVertexes][1] = 255;
+ tess.vertexColors[tess.numVertexes][2] = 255;
+ tess.numVertexes++;
+
+ VectorCopy( origin, temp );
+ VectorAdd( temp, vec1, temp );
+ VectorSubtract( temp, vec2, temp );
+ VectorCopy( temp, tess.xyz[tess.numVertexes] );
+ tess.texCoords[tess.numVertexes][0][0] = 0;
+ tess.texCoords[tess.numVertexes][0][1] = 1;
+ tess.vertexColors[tess.numVertexes][0] = 255;
+ tess.vertexColors[tess.numVertexes][1] = 255;
+ tess.vertexColors[tess.numVertexes][2] = 255;
+ tess.numVertexes++;
+
+ VectorCopy( origin, temp );
+ VectorAdd( temp, vec1, temp );
+ VectorAdd( temp, vec2, temp );
+ VectorCopy( temp, tess.xyz[tess.numVertexes] );
+ tess.texCoords[tess.numVertexes][0][0] = 1;
+ tess.texCoords[tess.numVertexes][0][1] = 1;
+ tess.vertexColors[tess.numVertexes][0] = 255;
+ tess.vertexColors[tess.numVertexes][1] = 255;
+ tess.vertexColors[tess.numVertexes][2] = 255;
+ tess.numVertexes++;
+
+ VectorCopy( origin, temp );
+ VectorSubtract( temp, vec1, temp );
+ VectorAdd( temp, vec2, temp );
+ VectorCopy( temp, tess.xyz[tess.numVertexes] );
+ tess.texCoords[tess.numVertexes][0][0] = 1;
+ tess.texCoords[tess.numVertexes][0][1] = 0;
+ tess.vertexColors[tess.numVertexes][0] = 255;
+ tess.vertexColors[tess.numVertexes][1] = 255;
+ tess.vertexColors[tess.numVertexes][2] = 255;
+ tess.numVertexes++;
+
+ tess.indexes[tess.numIndexes++] = 0;
+ tess.indexes[tess.numIndexes++] = 1;
+ tess.indexes[tess.numIndexes++] = 2;
+ tess.indexes[tess.numIndexes++] = 0;
+ tess.indexes[tess.numIndexes++] = 2;
+ tess.indexes[tess.numIndexes++] = 3;
+
+ RB_EndSurface();
+
+ // back to normal depth range
+ qglDepthRange( 0.0, 1.0 );
+}
+
+
+
+
+/*
+================
+RB_StageIteratorSky
+
+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( void ) {
+ if ( r_fastsky->integer ) {
+ return;
+ }
+
+ // go through all the polygons and project them onto
+ // the sky box to see which blocks on each side need
+ // to be drawn
+ RB_ClipSkyPolygons( &tess );
+
+ // 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.or.origin[0], backEnd.viewParms.or.origin[1], backEnd.viewParms.or.origin[2]);
+
+ DrawSkyBox( tess.shader );
+
+ qglPopMatrix();
+ }
+
+ // generate the vertexes for all the clouds, which will be drawn
+ // by the generic shader routine
+ R_BuildCloudData( &tess );
+
+ RB_StageIteratorGeneric();
+
+ // draw the inner skybox
+
+
+ // back to normal depth range
+ qglDepthRange( 0.0, 1.0 );
+
+ // note that sky was drawn so we will draw a sun later
+ backEnd.skyRenderedThisView = qtrue;
+}
+