/*
gl_rlight.c
(description)
Copyright (C) 1996-1997 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:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
$Id: gl_rlight.c,v 1.1.1.1 2001/03/06 09:33:35 lordhavoc Exp $
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif
#include <math.h>
#include <stdio.h>
#include "glquake.h"
int r_dlightframecount;
extern qboolean lighthalf;
/*
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 < MAX_LIGHTSTYLES; 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 BLEND RENDERING
*/
void
AddLightBlend (float r, float g, float b, float a2)
{
float a;
v_blend[3] = a = v_blend[3] + a2 * (1 - v_blend[3]);
a2 = a2 / a;
v_blend[0] = v_blend[0] * (1 - a2) + r * a2;
v_blend[1] = v_blend[1] * (1 - a2) + g * a2;
v_blend[2] = v_blend[2] * (1 - a2) + b * a2;
//Con_Printf("AddLightBlend(): %4.2f %4.2f %4.2f %4.6f\n", v_blend[0], v_blend[1], v_blend[2], v_blend[3]);
}
float bubble_sintable[33], bubble_costable[33];
void
R_InitBubble ()
{
int i;
float a;
float *bub_sin, *bub_cos;
bub_sin = bubble_sintable;
bub_cos = bubble_costable;
for (i = 32; i >= 0; i--) {
a = i / 32.0 * M_PI * 2;
*bub_sin++ = sin (a);
*bub_cos++ = cos (a);
}
}
void
R_RenderDlight (dlight_t *light)
{
int i, j;
vec3_t v;
float rad;
float *bub_sin, *bub_cos;
bub_sin = bubble_sintable;
bub_cos = bubble_costable;
rad = light->radius * 0.35;
VectorSubtract (light->origin, r_origin, v);
if (Length (v) < rad) { // view is inside the dlight
return;
}
glBegin (GL_TRIANGLE_FAN);
if (lighthalf)
glColor3f (light->color[0] * 0.5, light->color[1] * 0.5,
light->color[2] * 0.5);
else
glColor3fv (light->color);
for (i = 0; i < 3; i++)
v[i] = light->origin[i] - vpn[i] * rad;
glVertex3fv (v);
glColor3f (0, 0, 0);
for (i = 16; i >= 0; i--) {
for (j = 0; j < 3; j++)
v[j] = light->origin[j] + (vright[j] * (*bub_cos) +
vup[j] * (*bub_sin)) * rad;
bub_sin += 2;
bub_cos += 2;
glVertex3fv (v);
}
glEnd ();
// Don't glColor3ubv(lighthalf_v), as we reset in the function which
// calls this one, because this is called in a big loop.
}
/*
R_RenderDlights
*/
void
R_RenderDlights (void)
{
int i;
dlight_t *l;
if (!gl_dlight_polyblend->int_val)
return;
r_dlightframecount = r_framecount + 1; // because the count hasn't
// advanced yet for this frame
glDepthMask (GL_FALSE);
glDisable (GL_TEXTURE_2D);
glBlendFunc (GL_ONE, GL_ONE);
glShadeModel (GL_SMOOTH);
l = cl_dlights;
for (i = 0; i < MAX_DLIGHTS; i++, l++) {
if (l->die < cl.time || !l->radius)
continue;
R_RenderDlight (l);
}
if (!gl_dlight_smooth->int_val)
glShadeModel (GL_FLAT);
glColor3ubv (lighthalf_v);
glEnable (GL_TEXTURE_2D);
glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glDepthMask (GL_TRUE);
}
/*
DYNAMIC LIGHTS
*/
/*
R_MarkLights
*/
// LordHavoc: heavily modified, to eliminate unnecessary texture uploads,
// and support bmodel lighting better
void
R_MarkLights (vec3_t lightorigin, dlight_t *light, int bit, mnode_t *node)
{
mplane_t *splitplane;
float dist, l, maxdist;
msurface_t *surf;
int i, j, s, t;
vec3_t impact;
if (node->contents < 0)
return;
splitplane = node->plane;
dist = DotProduct (lightorigin, splitplane->normal) - splitplane->dist;
if (dist > light->radius) {
if (node->children[0]->contents >= 0) // save some time by not
// pushing another stack
// frame
R_MarkLights (lightorigin, light, bit, node->children[0]);
return;
}
if (dist < -light->radius) {
if (node->children[1]->contents >= 0) // save some time by not
// pushing another stack
// frame
R_MarkLights (lightorigin, light, bit, node->children[1]);
return;
}
maxdist = light->radius * light->radius;
// mark the polygons
surf = cl.worldmodel->surfaces + node->firstsurface;
for (i = 0; i < node->numsurfaces; i++, surf++) {
// LordHavoc: MAJOR dynamic light speedup here, eliminates marking of
// surfaces that are too far away from light, thus preventing
// unnecessary renders and uploads
for (j = 0; j < 3; j++)
impact[j] = lightorigin[j] - surf->plane->normal[j] * dist;
// clamp center of light to corner and check brightness
l =
DotProduct (impact,
surf->texinfo->vecs[0]) + surf->texinfo->vecs[0][3] -
surf->texturemins[0];
s = l + 0.5;
if (s < 0)
s = 0;
else if (s > surf->extents[0])
s = surf->extents[0];
s = l - s;
l =
DotProduct (impact,
surf->texinfo->vecs[1]) + surf->texinfo->vecs[1][3] -
surf->texturemins[1];
t = l + 0.5;
if (t < 0)
t = 0;
else if (t > surf->extents[1])
t = surf->extents[1];
t = l - t;
// compare to minimum light
if ((s * s + t * t + dist * dist) < maxdist) {
if (surf->dlightframe != r_dlightframecount) // not dynamic
// until now
{
surf->dlightbits = bit;
surf->dlightframe = r_dlightframecount;
} else // already dynamic
surf->dlightbits |= bit;
}
}
if (node->children[0]->contents >= 0) // save some time by not pushing
// another stack frame
R_MarkLights (lightorigin, light, bit, node->children[0]);
if (node->children[1]->contents >= 0) // save some time by not pushing
// another stack frame
R_MarkLights (lightorigin, light, bit, node->children[1]);
}
/*
R_PushDlights
*/
void
R_PushDlights (vec3_t entorigin)
{
int i;
dlight_t *l;
vec3_t lightorigin;
if (!gl_dlight_lightmap->int_val)
return;
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;
VectorSubtract (l->origin, entorigin, lightorigin);
R_MarkLights (lightorigin, l, 1 << i, cl.worldmodel->nodes);
}
}
/*
LIGHT SAMPLING
*/
mplane_t *lightplane;
vec3_t lightspot;
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 int 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 anything
// check for impact on this node
VectorCopy (mid, lightspot);
lightplane = plane;
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;
return r;
}