Source to 321/ref_gl/gl_light.c
/*
Copyright (C) 1997-2001 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 the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
// r_light.c
#include "gl_local.h"
int r_dlightframecount;
#define DLIGHT_CUTOFF 64
/*
=============================================================================
DYNAMIC LIGHTS BLEND RENDERING
=============================================================================
*/
void R_RenderDlight (dlight_t *light)
{
int i, j;
float a;
vec3_t v;
float rad;
rad = light->intensity * 0.35;
VectorSubtract (light->origin, r_origin, v);
#if 0
// FIXME?
if (VectorLength (v) < rad)
{ // view is inside the dlight
V_AddBlend (light->color[0], light->color[1], light->color[2], light->intensity * 0.0003, v_blend);
return;
}
#endif
qglBegin (GL_TRIANGLE_FAN);
qglColor3f (light->color[0]*0.2, light->color[1]*0.2, light->color[2]*0.2);
for (i=0 ; i<3 ; i++)
v[i] = light->origin[i] - vpn[i]*rad;
qglVertex3fv (v);
qglColor3f (0,0,0);
for (i=16 ; i>=0 ; i--)
{
a = i/16.0 * M_PI*2;
for (j=0 ; j<3 ; j++)
v[j] = light->origin[j] + vright[j]*cos(a)*rad
+ vup[j]*sin(a)*rad;
qglVertex3fv (v);
}
qglEnd ();
}
/*
=============
R_RenderDlights
=============
*/
void R_RenderDlights (void)
{
int i;
dlight_t *l;
if (!gl_flashblend->value)
return;
r_dlightframecount = r_framecount + 1; // because the count hasn't
// advanced yet for this frame
qglDepthMask (0);
qglDisable (GL_TEXTURE_2D);
qglShadeModel (GL_SMOOTH);
qglEnable (GL_BLEND);
qglBlendFunc (GL_ONE, GL_ONE);
l = r_newrefdef.dlights;
for (i=0 ; i<r_newrefdef.num_dlights ; i++, l++)
R_RenderDlight (l);
qglColor3f (1,1,1);
qglDisable (GL_BLEND);
qglEnable (GL_TEXTURE_2D);
qglBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
qglDepthMask (1);
}
/*
=============================================================================
DYNAMIC LIGHTS
=============================================================================
*/
/*
=============
R_MarkLights
=============
*/
void R_MarkLights (dlight_t *light, int bit, mnode_t *node)
{
cplane_t *splitplane;
float dist;
msurface_t *surf;
int i;
if (node->contents != -1)
return;
splitplane = node->plane;
dist = DotProduct (light->origin, splitplane->normal) - splitplane->dist;
if (dist > light->intensity-DLIGHT_CUTOFF)
{
R_MarkLights (light, bit, node->children[0]);
return;
}
if (dist < -light->intensity+DLIGHT_CUTOFF)
{
R_MarkLights (light, bit, node->children[1]);
return;
}
// mark the polygons
surf = r_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;
if (gl_flashblend->value)
return;
r_dlightframecount = r_framecount + 1; // because the count hasn't
// advanced yet for this frame
l = r_newrefdef.dlights;
for (i=0 ; i<r_newrefdef.num_dlights ; i++, l++)
R_MarkLights ( l, 1<<i, r_worldmodel->nodes );
}
/*
=============================================================================
LIGHT SAMPLING
=============================================================================
*/
vec3_t pointcolor;
cplane_t *lightplane; // used as shadow plane
vec3_t lightspot;
int RecursiveLightPoint (mnode_t *node, vec3_t start, vec3_t end)
{
float front, back, frac;
int side;
cplane_t *plane;
vec3_t mid;
msurface_t *surf;
int s, t, ds, dt;
int i;
mtexinfo_t *tex;
byte *lightmap;
int maps;
int r;
if (node->contents != -1)
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
VectorCopy (mid, lightspot);
lightplane = plane;
surf = r_worldmodel->surfaces + node->firstsurface;
for (i=0 ; i<node->numsurfaces ; i++, surf++)
{
if (surf->flags&(SURF_DRAWTURB|SURF_DRAWSKY))
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;
VectorCopy (vec3_origin, pointcolor);
if (lightmap)
{
vec3_t scale;
lightmap += 3*(dt * ((surf->extents[0]>>4)+1) + ds);
for (maps = 0 ; maps < MAXLIGHTMAPS && surf->styles[maps] != 255 ;
maps++)
{
for (i=0 ; i<3 ; i++)
scale[i] = gl_modulate->value*r_newrefdef.lightstyles[surf->styles[maps]].rgb[i];
pointcolor[0] += lightmap[0] * scale[0] * (1.0/255);
pointcolor[1] += lightmap[1] * scale[1] * (1.0/255);
pointcolor[2] += lightmap[2] * scale[2] * (1.0/255);
lightmap += 3*((surf->extents[0]>>4)+1) *
((surf->extents[1]>>4)+1);
}
}
return 1;
}
// go down back side
return RecursiveLightPoint (node->children[!side], mid, end);
}
/*
===============
R_LightPoint
===============
*/
void R_LightPoint (vec3_t p, vec3_t color)
{
vec3_t end;
float r;
int lnum;
dlight_t *dl;
float light;
vec3_t dist;
float add;
if (!r_worldmodel->lightdata)
{
color[0] = color[1] = color[2] = 1.0;
return;
}
end[0] = p[0];
end[1] = p[1];
end[2] = p[2] - 2048;
r = RecursiveLightPoint (r_worldmodel->nodes, p, end);
if (r == -1)
{
VectorCopy (vec3_origin, color);
}
else
{
VectorCopy (pointcolor, color);
}
//
// add dynamic lights
//
light = 0;
dl = r_newrefdef.dlights;
for (lnum=0 ; lnum<r_newrefdef.num_dlights ; lnum++, dl++)
{
VectorSubtract (currententity->origin,
dl->origin,
dist);
add = dl->intensity - VectorLength(dist);
add *= (1.0/256);
if (add > 0)
{
VectorMA (color, add, dl->color, color);
}
}
VectorScale (color, gl_modulate->value, color);
}
//===================================================================
static float s_blocklights[34*34*3];
/*
===============
R_AddDynamicLights
===============
*/
void R_AddDynamicLights (msurface_t *surf)
{
int lnum;
int sd, td;
float fdist, frad, fminlight;
vec3_t impact, local;
int s, t;
int i;
int smax, tmax;
mtexinfo_t *tex;
dlight_t *dl;
float *pfBL;
float fsacc, ftacc;
smax = (surf->extents[0]>>4)+1;
tmax = (surf->extents[1]>>4)+1;
tex = surf->texinfo;
for (lnum=0 ; lnum<r_newrefdef.num_dlights ; lnum++)
{
if ( !(surf->dlightbits & (1<<lnum) ) )
continue; // not lit by this light
dl = &r_newrefdef.dlights[lnum];
frad = dl->intensity;
fdist = DotProduct (dl->origin, surf->plane->normal) -
surf->plane->dist;
frad -= fabs(fdist);
// rad is now the highest intensity on the plane
fminlight = DLIGHT_CUTOFF; // FIXME: make configurable?
if (frad < fminlight)
continue;
fminlight = frad - fminlight;
for (i=0 ; i<3 ; i++)
{
impact[i] = dl->origin[i] -
surf->plane->normal[i]*fdist;
}
local[0] = DotProduct (impact, tex->vecs[0]) + tex->vecs[0][3] - surf->texturemins[0];
local[1] = DotProduct (impact, tex->vecs[1]) + tex->vecs[1][3] - surf->texturemins[1];
pfBL = s_blocklights;
for (t = 0, ftacc = 0 ; t<tmax ; t++, ftacc += 16)
{
td = local[1] - ftacc;
if ( td < 0 )
td = -td;
for ( s=0, fsacc = 0 ; s<smax ; s++, fsacc += 16, pfBL += 3)
{
sd = Q_ftol( local[0] - fsacc );
if ( sd < 0 )
sd = -sd;
if (sd > td)
fdist = sd + (td>>1);
else
fdist = td + (sd>>1);
if ( fdist < fminlight )
{
pfBL[0] += ( frad - fdist ) * dl->color[0];
pfBL[1] += ( frad - fdist ) * dl->color[1];
pfBL[2] += ( frad - fdist ) * dl->color[2];
}
}
}
}
}
/*
** R_SetCacheState
*/
void R_SetCacheState( msurface_t *surf )
{
int maps;
for (maps = 0 ; maps < MAXLIGHTMAPS && surf->styles[maps] != 255 ;
maps++)
{
surf->cached_light[maps] = r_newrefdef.lightstyles[surf->styles[maps]].white;
}
}
/*
===============
R_BuildLightMap
Combine and scale multiple lightmaps into the floating format in blocklights
===============
*/
void R_BuildLightMap (msurface_t *surf, byte *dest, int stride)
{
int smax, tmax;
int r, g, b, a, max;
int i, j, size;
byte *lightmap;
float scale[4];
int nummaps;
float *bl;
lightstyle_t *style;
int monolightmap;
if ( surf->texinfo->flags & (SURF_SKY|SURF_TRANS33|SURF_TRANS66|SURF_WARP) )
ri.Sys_Error (ERR_DROP, "R_BuildLightMap called for non-lit surface");
smax = (surf->extents[0]>>4)+1;
tmax = (surf->extents[1]>>4)+1;
size = smax*tmax;
if (size > (sizeof(s_blocklights)>>4) )
ri.Sys_Error (ERR_DROP, "Bad s_blocklights size");
// set to full bright if no light data
if (!surf->samples)
{
int maps;
for (i=0 ; i<size*3 ; i++)
s_blocklights[i] = 255;
for (maps = 0 ; maps < MAXLIGHTMAPS && surf->styles[maps] != 255 ;
maps++)
{
style = &r_newrefdef.lightstyles[surf->styles[maps]];
}
goto store;
}
// count the # of maps
for ( nummaps = 0 ; nummaps < MAXLIGHTMAPS && surf->styles[nummaps] != 255 ;
nummaps++)
;
lightmap = surf->samples;
// add all the lightmaps
if ( nummaps == 1 )
{
int maps;
for (maps = 0 ; maps < MAXLIGHTMAPS && surf->styles[maps] != 255 ;
maps++)
{
bl = s_blocklights;
for (i=0 ; i<3 ; i++)
scale[i] = gl_modulate->value*r_newrefdef.lightstyles[surf->styles[maps]].rgb[i];
if ( scale[0] == 1.0F &&
scale[1] == 1.0F &&
scale[2] == 1.0F )
{
for (i=0 ; i<size ; i++, bl+=3)
{
bl[0] = lightmap[i*3+0];
bl[1] = lightmap[i*3+1];
bl[2] = lightmap[i*3+2];
}
}
else
{
for (i=0 ; i<size ; i++, bl+=3)
{
bl[0] = lightmap[i*3+0] * scale[0];
bl[1] = lightmap[i*3+1] * scale[1];
bl[2] = lightmap[i*3+2] * scale[2];
}
}
lightmap += size*3; // skip to next lightmap
}
}
else
{
int maps;
memset( s_blocklights, 0, sizeof( s_blocklights[0] ) * size * 3 );
for (maps = 0 ; maps < MAXLIGHTMAPS && surf->styles[maps] != 255 ;
maps++)
{
bl = s_blocklights;
for (i=0 ; i<3 ; i++)
scale[i] = gl_modulate->value*r_newrefdef.lightstyles[surf->styles[maps]].rgb[i];
if ( scale[0] == 1.0F &&
scale[1] == 1.0F &&
scale[2] == 1.0F )
{
for (i=0 ; i<size ; i++, bl+=3 )
{
bl[0] += lightmap[i*3+0];
bl[1] += lightmap[i*3+1];
bl[2] += lightmap[i*3+2];
}
}
else
{
for (i=0 ; i<size ; i++, bl+=3)
{
bl[0] += lightmap[i*3+0] * scale[0];
bl[1] += lightmap[i*3+1] * scale[1];
bl[2] += lightmap[i*3+2] * scale[2];
}
}
lightmap += size*3; // skip to next lightmap
}
}
// add all the dynamic lights
if (surf->dlightframe == r_framecount)
R_AddDynamicLights (surf);
// put into texture format
store:
stride -= (smax<<2);
bl = s_blocklights;
monolightmap = gl_monolightmap->string[0];
if ( monolightmap == '0' )
{
for (i=0 ; i<tmax ; i++, dest += stride)
{
for (j=0 ; j<smax ; j++)
{
r = Q_ftol( bl[0] );
g = Q_ftol( bl[1] );
b = Q_ftol( bl[2] );
// catch negative lights
if (r < 0)
r = 0;
if (g < 0)
g = 0;
if (b < 0)
b = 0;
/*
** determine the brightest of the three color components
*/
if (r > g)
max = r;
else
max = g;
if (b > max)
max = b;
/*
** alpha is ONLY used for the mono lightmap case. For this reason
** we set it to the brightest of the color components so that
** things don't get too dim.
*/
a = max;
/*
** rescale all the color components if the intensity of the greatest
** channel exceeds 1.0
*/
if (max > 255)
{
float t = 255.0F / max;
r = r*t;
g = g*t;
b = b*t;
a = a*t;
}
dest[0] = r;
dest[1] = g;
dest[2] = b;
dest[3] = a;
bl += 3;
dest += 4;
}
}
}
else
{
for (i=0 ; i<tmax ; i++, dest += stride)
{
for (j=0 ; j<smax ; j++)
{
r = Q_ftol( bl[0] );
g = Q_ftol( bl[1] );
b = Q_ftol( bl[2] );
// catch negative lights
if (r < 0)
r = 0;
if (g < 0)
g = 0;
if (b < 0)
b = 0;
/*
** determine the brightest of the three color components
*/
if (r > g)
max = r;
else
max = g;
if (b > max)
max = b;
/*
** alpha is ONLY used for the mono lightmap case. For this reason
** we set it to the brightest of the color components so that
** things don't get too dim.
*/
a = max;
/*
** rescale all the color components if the intensity of the greatest
** channel exceeds 1.0
*/
if (max > 255)
{
float t = 255.0F / max;
r = r*t;
g = g*t;
b = b*t;
a = a*t;
}
/*
** So if we are doing alpha lightmaps we need to set the R, G, and B
** components to 0 and we need to set alpha to 1-alpha.
*/
switch ( monolightmap )
{
case 'L':
case 'I':
r = a;
g = b = 0;
break;
case 'C':
// try faking colored lighting
a = 255 - ((r+g+b)/3);
r *= a/255.0;
g *= a/255.0;
b *= a/255.0;
break;
case 'A':
default:
r = g = b = 0;
a = 255 - a;
break;
}
dest[0] = r;
dest[1] = g;
dest[2] = b;
dest[3] = a;
bl += 3;
dest += 4;
}
}
}
}