ref: 42681cb8ee1bab11448ddda478f5791b6b7699e9
dir: /r_light.c/
#include <u.h> #include <libc.h> #include "dat.h" #include "quakedef.h" #include "fns.h" int r_dlightframecount; /* ================== R_AnimateLight ================== */ void R_AnimateLight (void) { int i,j,k; // // light animations // 'm' is normal light, 'a' is no light, 'z' is double bright i = (int)(cl.time*10); for (j=0 ; j<Nlights ; j++) { if (!cl_lightstyle[j].length) { d_lightstylevalue[j] = 256; continue; } k = i % cl_lightstyle[j].length; k = cl_lightstyle[j].map[k] - 'a'; k = k*22; d_lightstylevalue[j] = k; } } /* ============================================================================= DYNAMIC LIGHTS ============================================================================= */ /* ============= R_MarkLights ============= */ void R_MarkLights (dlight_t *light, int bit, mnode_t *node) { mplane_t *splitplane; float dist; msurface_t *surf; int i; if (node->contents < 0) return; splitplane = node->plane; dist = DotProduct (light->origin, splitplane->normal) - splitplane->dist; if (dist > light->radius) { R_MarkLights (light, bit, node->children[0]); return; } if (dist < -light->radius) { R_MarkLights (light, bit, node->children[1]); return; } // mark the polygons surf = cl.worldmodel->surfaces + node->firstsurface; for (i=0 ; i<node->numsurfaces ; i++, surf++) { if (surf->dlightframe != r_dlightframecount) { surf->dlightbits = 0; surf->dlightframe = r_dlightframecount; } surf->dlightbits |= bit; } R_MarkLights (light, bit, node->children[0]); R_MarkLights (light, bit, node->children[1]); } /* ============= R_PushDlights ============= */ void R_PushDlights (void) { int i; dlight_t *l; r_dlightframecount = r_framecount + 1; // because the count hasn't // advanced yet for this frame l = cl_dlights; for (i=0 ; i<MAX_DLIGHTS ; i++, l++) { if (l->die < cl.time || !l->radius) continue; R_MarkLights ( l, 1<<i, cl.worldmodel->nodes ); } } /* ============================================================================= LIGHT SAMPLING ============================================================================= */ int RecursiveLightPoint (mnode_t *node, vec3_t start, vec3_t end) { int r; float front, back, frac; int side; mplane_t *plane; vec3_t mid; msurface_t *surf; int s, t, ds, dt; int i; mtexinfo_t *tex; byte *lightmap; unsigned scale; int maps; if (node->contents < 0) return -1; // didn't hit anything // calculate mid point // FIXME: optimize for axial plane = node->plane; front = DotProduct (start, plane->normal) - plane->dist; back = DotProduct (end, plane->normal) - plane->dist; side = front < 0; if ( (back < 0) == side) return RecursiveLightPoint (node->children[side], start, end); frac = front / (front-back); mid[0] = start[0] + (end[0] - start[0])*frac; mid[1] = start[1] + (end[1] - start[1])*frac; mid[2] = start[2] + (end[2] - start[2])*frac; // go down front side r = RecursiveLightPoint (node->children[side], start, mid); if (r >= 0) return r; // hit something if ( (back < 0) == side ) return -1; // didn't hit anuthing // check for impact on this node surf = cl.worldmodel->surfaces + node->firstsurface; for (i=0 ; i<node->numsurfaces ; i++, surf++) { if (surf->flags & SURF_DRAWTILED) continue; // no lightmaps tex = surf->texinfo; s = DotProduct (mid, tex->vecs[0]) + tex->vecs[0][3]; t = DotProduct (mid, tex->vecs[1]) + tex->vecs[1][3];; if (s < surf->texturemins[0] || t < surf->texturemins[1]) continue; ds = s - surf->texturemins[0]; dt = t - surf->texturemins[1]; if ( ds > surf->extents[0] || dt > surf->extents[1] ) continue; if (!surf->samples) return 0; ds >>= 4; dt >>= 4; lightmap = surf->samples; r = 0; if (lightmap) { lightmap += dt * ((surf->extents[0]>>4)+1) + ds; for (maps = 0 ; maps < MAXLIGHTMAPS && surf->styles[maps] != 255 ; maps++) { scale = d_lightstylevalue[surf->styles[maps]]; r += *lightmap * scale; lightmap += ((surf->extents[0]>>4)+1) * ((surf->extents[1]>>4)+1); } r >>= 8; } return r; } // go down back side return RecursiveLightPoint (node->children[!side], mid, end); } int R_LightPoint (vec3_t p) { vec3_t end; int r; if (!cl.worldmodel->lightdata) return 255; end[0] = p[0]; end[1] = p[1]; end[2] = p[2] - 2048; r = RecursiveLightPoint (cl.worldmodel->nodes, p, end); if (r == -1) r = 0; if (r < r_refdef.ambientlight) r = r_refdef.ambientlight; return r; }