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Diffstat (limited to 'src/renderer/tr_shadows.c')
-rw-r--r-- | src/renderer/tr_shadows.c | 342 |
1 files changed, 342 insertions, 0 deletions
diff --git a/src/renderer/tr_shadows.c b/src/renderer/tr_shadows.c new file mode 100644 index 0000000..19d4046 --- /dev/null +++ b/src/renderer/tr_shadows.c @@ -0,0 +1,342 @@ +/* +=========================================================================== +Copyright (C) 1999-2005 Id Software, Inc. +Copyright (C) 2000-2006 Tim Angus + +This file is part of Tremulous. + +Tremulous 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. + +Tremulous 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 Tremulous; if not, write to the Free Software +Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +=========================================================================== +*/ +#include "tr_local.h" + + +/* + + for a projection shadow: + + point[x] += light vector * ( z - shadow plane ) + point[y] += + point[z] = shadow plane + + 1 0 light[x] / light[z] + +*/ + +typedef struct { + int i2; + int facing; +} edgeDef_t; + +#define MAX_EDGE_DEFS 32 + +static edgeDef_t edgeDefs[SHADER_MAX_VERTEXES][MAX_EDGE_DEFS]; +static int numEdgeDefs[SHADER_MAX_VERTEXES]; +static int facing[SHADER_MAX_INDEXES/3]; + +void R_AddEdgeDef( int i1, int i2, int facing ) { + int c; + + c = numEdgeDefs[ i1 ]; + if ( c == MAX_EDGE_DEFS ) { + return; // overflow + } + edgeDefs[ i1 ][ c ].i2 = i2; + edgeDefs[ i1 ][ c ].facing = facing; + + numEdgeDefs[ i1 ]++; +} + +void R_RenderShadowEdges( void ) { + int i; + +#if 0 + int numTris; + + // dumb way -- render every triangle's edges + numTris = tess.numIndexes / 3; + + for ( i = 0 ; i < numTris ; i++ ) { + int i1, i2, i3; + + if ( !facing[i] ) { + continue; + } + + i1 = tess.indexes[ i*3 + 0 ]; + i2 = tess.indexes[ i*3 + 1 ]; + i3 = tess.indexes[ i*3 + 2 ]; + + qglBegin( GL_TRIANGLE_STRIP ); + qglVertex3fv( tess.xyz[ i1 ] ); + qglVertex3fv( tess.xyz[ i1 + tess.numVertexes ] ); + qglVertex3fv( tess.xyz[ i2 ] ); + qglVertex3fv( tess.xyz[ i2 + tess.numVertexes ] ); + qglVertex3fv( tess.xyz[ i3 ] ); + qglVertex3fv( tess.xyz[ i3 + tess.numVertexes ] ); + qglVertex3fv( tess.xyz[ i1 ] ); + qglVertex3fv( tess.xyz[ i1 + tess.numVertexes ] ); + qglEnd(); + } +#else + int c, c2; + int j, k; + int i2; + int c_edges, c_rejected; + int hit[2]; + + // an edge is NOT a silhouette edge if its face doesn't face the light, + // or if it has a reverse paired edge that also faces the light. + // A well behaved polyhedron would have exactly two faces for each edge, + // but lots of models have dangling edges or overfanned edges + c_edges = 0; + c_rejected = 0; + + for ( i = 0 ; i < tess.numVertexes ; i++ ) { + c = numEdgeDefs[ i ]; + for ( j = 0 ; j < c ; j++ ) { + if ( !edgeDefs[ i ][ j ].facing ) { + continue; + } + + hit[0] = 0; + hit[1] = 0; + + i2 = edgeDefs[ i ][ j ].i2; + c2 = numEdgeDefs[ i2 ]; + for ( k = 0 ; k < c2 ; k++ ) { + if ( edgeDefs[ i2 ][ k ].i2 == i ) { + hit[ edgeDefs[ i2 ][ k ].facing ]++; + } + } + + // if it doesn't share the edge with another front facing + // triangle, it is a sil edge + if ( hit[ 1 ] == 0 ) { + qglBegin( GL_TRIANGLE_STRIP ); + qglVertex3fv( tess.xyz[ i ] ); + qglVertex3fv( tess.xyz[ i + tess.numVertexes ] ); + qglVertex3fv( tess.xyz[ i2 ] ); + qglVertex3fv( tess.xyz[ i2 + tess.numVertexes ] ); + qglEnd(); + c_edges++; + } else { + c_rejected++; + } + } + } +#endif +} + +/* +================= +RB_ShadowTessEnd + +triangleFromEdge[ v1 ][ v2 ] + + + set triangle from edge( v1, v2, tri ) + if ( facing[ triangleFromEdge[ v1 ][ v2 ] ] && !facing[ triangleFromEdge[ v2 ][ v1 ] ) { + } +================= +*/ +void RB_ShadowTessEnd( void ) { + int i; + int numTris; + vec3_t lightDir; + + // we can only do this if we have enough space in the vertex buffers + if ( tess.numVertexes >= SHADER_MAX_VERTEXES / 2 ) { + return; + } + + if ( glConfig.stencilBits < 4 ) { + return; + } + + VectorCopy( backEnd.currentEntity->lightDir, lightDir ); + + // project vertexes away from light direction + for ( i = 0 ; i < tess.numVertexes ; i++ ) { + VectorMA( tess.xyz[i], -512, lightDir, tess.xyz[i+tess.numVertexes] ); + } + + // decide which triangles face the light + Com_Memset( numEdgeDefs, 0, 4 * tess.numVertexes ); + + numTris = tess.numIndexes / 3; + for ( i = 0 ; i < numTris ; i++ ) { + int i1, i2, i3; + vec3_t d1, d2, normal; + float *v1, *v2, *v3; + float d; + + i1 = tess.indexes[ i*3 + 0 ]; + i2 = tess.indexes[ i*3 + 1 ]; + i3 = tess.indexes[ i*3 + 2 ]; + + v1 = tess.xyz[ i1 ]; + v2 = tess.xyz[ i2 ]; + v3 = tess.xyz[ i3 ]; + + VectorSubtract( v2, v1, d1 ); + VectorSubtract( v3, v1, d2 ); + CrossProduct( d1, d2, normal ); + + d = DotProduct( normal, lightDir ); + if ( d > 0 ) { + facing[ i ] = 1; + } else { + facing[ i ] = 0; + } + + // create the edges + R_AddEdgeDef( i1, i2, facing[ i ] ); + R_AddEdgeDef( i2, i3, facing[ i ] ); + R_AddEdgeDef( i3, i1, facing[ i ] ); + } + + // draw the silhouette edges + + GL_Bind( tr.whiteImage ); + qglEnable( GL_CULL_FACE ); + GL_State( GLS_SRCBLEND_ONE | GLS_DSTBLEND_ZERO ); + qglColor3f( 0.2f, 0.2f, 0.2f ); + + // don't write to the color buffer + qglColorMask( GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE ); + + qglEnable( GL_STENCIL_TEST ); + qglStencilFunc( GL_ALWAYS, 1, 255 ); + + // mirrors have the culling order reversed + if ( backEnd.viewParms.isMirror ) { + qglCullFace( GL_FRONT ); + qglStencilOp( GL_KEEP, GL_KEEP, GL_INCR ); + + R_RenderShadowEdges(); + + qglCullFace( GL_BACK ); + qglStencilOp( GL_KEEP, GL_KEEP, GL_DECR ); + + R_RenderShadowEdges(); + } else { + qglCullFace( GL_BACK ); + qglStencilOp( GL_KEEP, GL_KEEP, GL_INCR ); + + R_RenderShadowEdges(); + + qglCullFace( GL_FRONT ); + qglStencilOp( GL_KEEP, GL_KEEP, GL_DECR ); + + R_RenderShadowEdges(); + } + + + // reenable writing to the color buffer + qglColorMask( GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE ); +} + + +/* +================= +RB_ShadowFinish + +Darken everything that is is a shadow volume. +We have to delay this until everything has been shadowed, +because otherwise shadows from different body parts would +overlap and double darken. +================= +*/ +void RB_ShadowFinish( void ) { + if ( r_shadows->integer != 2 ) { + return; + } + if ( glConfig.stencilBits < 4 ) { + return; + } + qglEnable( GL_STENCIL_TEST ); + qglStencilFunc( GL_NOTEQUAL, 0, 255 ); + + qglDisable (GL_CLIP_PLANE0); + qglDisable (GL_CULL_FACE); + + GL_Bind( tr.whiteImage ); + + qglLoadIdentity (); + + qglColor3f( 0.6f, 0.6f, 0.6f ); + GL_State( GLS_DEPTHMASK_TRUE | GLS_SRCBLEND_DST_COLOR | GLS_DSTBLEND_ZERO ); + +// qglColor3f( 1, 0, 0 ); +// GL_State( GLS_DEPTHMASK_TRUE | GLS_SRCBLEND_ONE | GLS_DSTBLEND_ZERO ); + + qglBegin( GL_QUADS ); + qglVertex3f( -100, 100, -10 ); + qglVertex3f( 100, 100, -10 ); + qglVertex3f( 100, -100, -10 ); + qglVertex3f( -100, -100, -10 ); + qglEnd (); + + qglColor4f(1,1,1,1); + qglDisable( GL_STENCIL_TEST ); +} + + +/* +================= +RB_ProjectionShadowDeform + +================= +*/ +void RB_ProjectionShadowDeform( void ) { + float *xyz; + int i; + float h; + vec3_t ground; + vec3_t light; + float groundDist; + float d; + vec3_t lightDir; + + xyz = ( float * ) tess.xyz; + + ground[0] = backEnd.or.axis[0][2]; + ground[1] = backEnd.or.axis[1][2]; + ground[2] = backEnd.or.axis[2][2]; + + groundDist = backEnd.or.origin[2] - backEnd.currentEntity->e.shadowPlane; + + VectorCopy( backEnd.currentEntity->lightDir, lightDir ); + d = DotProduct( lightDir, ground ); + // don't let the shadows get too long or go negative + if ( d < 0.5 ) { + VectorMA( lightDir, (0.5 - d), ground, lightDir ); + d = DotProduct( lightDir, ground ); + } + d = 1.0 / d; + + light[0] = lightDir[0] * d; + light[1] = lightDir[1] * d; + light[2] = lightDir[2] * d; + + for ( i = 0; i < tess.numVertexes; i++, xyz += 4 ) { + h = DotProduct( xyz, ground ) + groundDist; + + xyz[0] -= light[0] * h; + xyz[1] -= light[1] * h; + xyz[2] -= light[2] * h; + } +} |