quakeforge/libs/video/renderer/gl/gl_rsurf.c

865 lines
21 KiB
C

/*
gl_rsurf.c
surface-related refresh code
Copyright (C) 1996-1997 Id Software, Inc.
Copyright (C) 2000 Joseph Carter <knghtbrd@debian.org>
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
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
static __attribute__ ((used)) const char rcsid[] =
"$Id$";
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif
#include <math.h>
#include <stdio.h>
#include "QF/cvar.h"
#include "QF/render.h"
#include "QF/sys.h"
#include "QF/GL/defines.h"
#include "QF/GL/funcs.h"
#include "QF/GL/qf_lightmap.h"
#include "QF/GL/qf_rmain.h"
#include "QF/GL/qf_rsurf.h"
#include "QF/GL/qf_sky.h"
#include "QF/GL/qf_textures.h"
#include "QF/GL/qf_vid.h"
#include "compat.h"
#include "r_cvar.h"
#include "r_local.h"
#include "r_shared.h"
int skytexturenum;
glpoly_t *fullbright_polys[MAX_GLTEXTURES];
msurface_t *waterchain = NULL;
msurface_t **waterchain_tail = &waterchain;
msurface_t *sky_chain;
msurface_t **sky_chain_tail;
#define CHAIN_SURF_F2B(surf,chain) \
do { \
*(chain##_tail) = (surf); \
(chain##_tail) = &(surf)->texturechain; \
*(chain##_tail) = 0; \
} while (0)
#define CHAIN_SURF_B2F(surf,chain) \
do { \
(surf)->texturechain = (chain); \
(chain) = (surf); \
} while (0)
extern int lightmap_textures;
extern qboolean lightmap_modified[MAX_LIGHTMAPS];
extern glpoly_t *lightmap_polys[MAX_LIGHTMAPS];
extern glRect_t lightmap_rectchange[MAX_LIGHTMAPS];
/*
R_TextureAnimation
Returns the proper texture for a given time and base texture
*/
texture_t *
R_TextureAnimation (msurface_t *surf)
{
texture_t *base = surf->texinfo->texture;
int count, relative;
if (currententity->frame) {
if (base->alternate_anims)
base = base->alternate_anims;
}
relative = (int) (r_realtime * 10) % base->anim_total;
count = 0;
while (base->anim_min > relative || base->anim_max <= relative) {
base = base->anim_next;
if (!base)
Sys_Error ("R_TextureAnimation: broken cycle");
if (++count > 100)
Sys_Error ("R_TextureAnimation: infinite cycle");
}
return base;
}
// BRUSH MODELS ===============================================================
static void
R_RenderFullbrights (void)
{
float *v;
int i, j;
glpoly_t *p;
for (i = 1; i < MAX_GLTEXTURES; i++) {
if (!fullbright_polys[i])
continue;
qfglBindTexture (GL_TEXTURE_2D, i);
for (p = fullbright_polys[i]; p; p = p->fb_chain) {
qfglBegin (GL_POLYGON);
for (j = 0, v = p->verts[0]; j < p->numverts; j++, v += VERTEXSIZE)
{
qfglTexCoord2fv (&v[3]);
qfglVertex3fv (v);
}
qfglEnd ();
}
}
}
static inline void
R_RenderBrushPoly_3 (msurface_t *fa)
{
float *v;
int i;
c_brush_polys++;
qfglBegin (GL_POLYGON);
v = fa->polys->verts[0];
for (i = 0; i < fa->polys->numverts; i++, v += VERTEXSIZE) {
qglMultiTexCoord2fv (gl_mtex_enum + 0, &v[3]);
qglMultiTexCoord2fv (gl_mtex_enum + 1, &v[5]);
qglMultiTexCoord2fv (gl_mtex_enum + 2, &v[3]);
qfglVertex3fv (v);
}
qfglEnd ();
}
static inline void
R_RenderBrushPoly_2 (msurface_t *fa)
{
float *v;
int i;
c_brush_polys++;
qfglBegin (GL_POLYGON);
v = fa->polys->verts[0];
for (i = 0; i < fa->polys->numverts; i++, v += VERTEXSIZE) {
qglMultiTexCoord2fv (gl_mtex_enum + 0, &v[3]);
qglMultiTexCoord2fv (gl_mtex_enum + 1, &v[5]);
qfglVertex3fv (v);
}
qfglEnd ();
}
static inline void
R_RenderBrushPoly_1 (msurface_t *fa)
{
float *v;
int i;
c_brush_polys++;
qfglBegin (GL_POLYGON);
v = fa->polys->verts[0];
for (i = 0; i < fa->polys->numverts; i++, v += VERTEXSIZE) {
qfglTexCoord2fv (&v[3]);
qfglVertex3fv (v);
}
qfglEnd ();
}
static inline void
R_AddToLightmapChain (msurface_t *fa)
{
int maps, smax, tmax;
glRect_t *theRect;
// add the poly to the proper lightmap chain
fa->polys->chain = lightmap_polys[fa->lightmaptexturenum];
lightmap_polys[fa->lightmaptexturenum] = fa->polys;
// check for lightmap modification
for (maps = 0; maps < MAXLIGHTMAPS && fa->styles[maps] != 255; maps++)
if (d_lightstylevalue[fa->styles[maps]] != fa->cached_light[maps])
goto dynamic;
if ((fa->dlightframe == r_framecount) || fa->cached_dlight) {
dynamic:
if (r_dynamic->int_val) {
lightmap_modified[fa->lightmaptexturenum] = true;
theRect = &lightmap_rectchange[fa->lightmaptexturenum];
if (fa->light_t < theRect->t) {
if (theRect->h)
theRect->h += theRect->t - fa->light_t;
theRect->t = fa->light_t;
}
if (fa->light_s < theRect->l) {
if (theRect->w)
theRect->w += theRect->l - fa->light_s;
theRect->l = fa->light_s;
}
smax = (fa->extents[0] >> 4) + 1;
tmax = (fa->extents[1] >> 4) + 1;
if ((theRect->w + theRect->l) < (fa->light_s + smax))
theRect->w = (fa->light_s - theRect->l) + smax;
if ((theRect->h + theRect->t) < (fa->light_t + tmax))
theRect->h = (fa->light_t - theRect->t) + tmax;
R_BuildLightMap (fa);
}
}
}
void
R_DrawWaterSurfaces (void)
{
int i;
msurface_t *s;
if (!waterchain)
return;
// go back to the world matrix
qfglLoadMatrixf (r_world_matrix);
if (cl_wateralpha < 1.0) {
qfglDepthMask (GL_FALSE);
color_white[3] = cl_wateralpha * 255;
qfglColor4ubv (color_white);
}
i = -1;
for (s = waterchain; s; s = s->texturechain) {
if (i != s->texinfo->texture->gl_texturenum) {
i = s->texinfo->texture->gl_texturenum;
qfglBindTexture (GL_TEXTURE_2D, i);
}
EmitWaterPolys (s);
}
waterchain = NULL;
waterchain_tail = &waterchain;
if (cl_wateralpha < 1.0) {
qfglDepthMask (GL_TRUE);
qfglColor3ubv (color_white);
}
}
static inline void
DrawTextureChains (void)
{
int i;
msurface_t *s;
texture_t *tex;
if (gl_mtex_active_tmus >= 2) {
// Lightmaps
qglActiveTexture (gl_mtex_enum + 1);
qfglEnable (GL_TEXTURE_2D);
// Base Texture
qglActiveTexture (gl_mtex_enum + 0);
qfglTexEnvf (GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
for (i = 0; i < r_worldentity.model->numtextures; i++) {
tex = r_worldentity.model->textures[i];
if (!tex)
continue;
qfglBindTexture (GL_TEXTURE_2D, tex->gl_texturenum);
if (tex->gl_fb_texturenum && gl_mtex_fullbright) {
qglActiveTexture (gl_mtex_enum + 2);
qfglEnable (GL_TEXTURE_2D);
qfglBindTexture (GL_TEXTURE_2D, tex->gl_fb_texturenum);
qglActiveTexture (gl_mtex_enum + 1);
for (s = tex->texturechain; s; s = s->texturechain) {
qfglBindTexture (GL_TEXTURE_2D, lightmap_textures +
s->lightmaptexturenum);
R_RenderBrushPoly_3 (s);
}
qglActiveTexture (gl_mtex_enum + 2);
qfglDisable (GL_TEXTURE_2D);
qglActiveTexture (gl_mtex_enum + 0);
} else {
qglActiveTexture (gl_mtex_enum + 1);
for (s = tex->texturechain; s; s = s->texturechain) {
qfglBindTexture (GL_TEXTURE_2D, lightmap_textures +
s->lightmaptexturenum);
R_RenderBrushPoly_2 (s);
}
qglActiveTexture (gl_mtex_enum + 0);
}
tex->texturechain = NULL;
tex->texturechain_tail = &tex->texturechain;
}
// Turn off lightmaps for other entities
qglActiveTexture (gl_mtex_enum + 1);
qfglDisable (GL_TEXTURE_2D);
// Reset mode for default TMU
qglActiveTexture (gl_mtex_enum + 0);
qfglTexEnvf (GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
} else {
qfglDisable (GL_BLEND);
for (i = 0; i < r_worldentity.model->numtextures; i++) {
tex = r_worldentity.model->textures[i];
if (!tex)
continue;
qfglBindTexture (GL_TEXTURE_2D, tex->gl_texturenum);
for (s = tex->texturechain; s; s = s->texturechain)
R_RenderBrushPoly_1 (s);
tex->texturechain = NULL;
tex->texturechain_tail = &tex->texturechain;
}
qfglEnable (GL_BLEND);
}
tex = r_notexture_mip;
tex->texturechain = NULL;
tex->texturechain_tail = &tex->texturechain;
}
void
R_DrawBrushModel (entity_t *e)
{
float dot, radius;
float color[4], watercolor[4];
int i;
unsigned int k;
model_t *model;
mplane_t *pplane;
msurface_t *psurf;
qboolean rotated;
vec3_t mins, maxs;
model = e->model;
if (e->angles[0] || e->angles[1] || e->angles[2]) {
rotated = true;
radius = model->radius;
#if 0 //QSG FIXME
if (e->scale != 1.0)
radius *= e->scale;
#endif
if (R_CullSphere (e->origin, radius))
return;
} else {
rotated = false;
VectorAdd (e->origin, model->mins, mins);
VectorAdd (e->origin, model->maxs, maxs);
#if 0 // QSG FIXME
if (e->scale != 1.0) {
VectorScale (mins, e->scale, mins);
VectorScale (maxs, e->scale, maxs);
}
#endif
if (R_CullBox (mins, maxs))
return;
}
VectorCopy (e->colormod, color);
VectorCopy (color, watercolor);
color[3] = e->colormod[3];
qfglColor4fv (color);
if (color[3] < 1.0)
qfglDepthMask (GL_FALSE);
memset (lightmap_polys, 0, sizeof (lightmap_polys));
memset (fullbright_polys, 0, sizeof (fullbright_polys));
VectorSubtract (r_refdef.vieworg, e->origin, modelorg);
if (rotated) {
vec3_t temp, forward, right, up;
VectorCopy (modelorg, temp);
AngleVectors (e->angles, forward, right, up);
modelorg[0] = DotProduct (temp, forward);
modelorg[1] = -DotProduct (temp, right);
modelorg[2] = DotProduct (temp, up);
}
psurf = &model->surfaces[model->firstmodelsurface];
// calculate dynamic lighting for bmodel if it's not an instanced model
if (model->firstmodelsurface != 0 && r_dlight_lightmap->int_val) {
vec3_t lightorigin;
for (k = 0; k < r_maxdlights; k++) {
if ((r_dlights[k].die < r_realtime) || (!r_dlights[k].radius))
continue;
VectorSubtract (r_dlights[k].origin, e->origin, lightorigin);
R_RecursiveMarkLights (lightorigin, &r_dlights[k], 1 << k,
model->nodes + model->hulls[0].firstclipnode);
}
}
qfglPushMatrix ();
e->angles[0] = -e->angles[0]; // stupid quake bug
R_RotateForEntity (e);
e->angles[0] = -e->angles[0]; // stupid quake bug
// Build lightmap chains
for (i = 0; i < model->nummodelsurfaces; i++, psurf++) {
if (psurf->flags & (SURF_DRAWTURB | SURF_DRAWSKY))
continue;
R_AddToLightmapChain (psurf);
}
if (gl_mtex_active_tmus >= 2)
R_CalcLightmaps ();
psurf = &model->surfaces[model->firstmodelsurface];
// draw texture
for (i = 0; i < model->nummodelsurfaces; i++, psurf++) {
// find which side of the node we are on
pplane = psurf->plane;
dot = DotProduct (modelorg, pplane->normal) - pplane->dist;
// draw the polygon
if (((psurf->flags & SURF_PLANEBACK) && (dot < -BACKFACE_EPSILON)) ||
(!(psurf->flags & SURF_PLANEBACK) && (dot > BACKFACE_EPSILON))) {
if (psurf->flags & SURF_DRAWTURB) {
qfglBindTexture (GL_TEXTURE_2D,
psurf->texinfo->texture->gl_texturenum);
if (cl_wateralpha < 1.0) {
if (color[3] >= 1.0)
qfglDepthMask (GL_FALSE);
watercolor[3] = color[3] * cl_wateralpha;
qfglColor4fv (watercolor);
EmitWaterPolys (psurf);
qfglColor4fv (color);
if (color[3] >= 1.0)
qfglDepthMask (GL_TRUE);
} else {
EmitWaterPolys (psurf);
}
} else if (psurf->flags & SURF_DRAWSKY) {
// QSG FIXME: add modelalpha support for sky brushes
CHAIN_SURF_F2B (psurf, sky_chain);
} else {
texture_t *tex;
if (!psurf->texinfo->texture->anim_total)
tex = psurf->texinfo->texture;
else
tex = R_TextureAnimation (psurf);
if (gl_mtex_active_tmus >= 2) {
if (tex->gl_fb_texturenum && gl_mtex_fullbright) {
qglActiveTexture (gl_mtex_enum + 2);
qfglEnable (GL_TEXTURE_2D);
qfglBindTexture (GL_TEXTURE_2D, tex->gl_fb_texturenum);
qglActiveTexture (gl_mtex_enum + 1);
qfglEnable (GL_TEXTURE_2D);
qfglBindTexture (GL_TEXTURE_2D, lightmap_textures +
psurf->lightmaptexturenum);
qglActiveTexture (gl_mtex_enum + 0);
qfglBindTexture (GL_TEXTURE_2D, tex->gl_texturenum);
R_RenderBrushPoly_3 (psurf);
qglActiveTexture (gl_mtex_enum + 2);
qfglDisable (GL_TEXTURE_2D);
qglActiveTexture (gl_mtex_enum + 1);
qfglDisable (GL_TEXTURE_2D);
qglActiveTexture (gl_mtex_enum + 0);
} else {
qglActiveTexture (gl_mtex_enum + 1);
qfglEnable (GL_TEXTURE_2D);
qfglBindTexture (GL_TEXTURE_2D, lightmap_textures +
psurf->lightmaptexturenum);
qglActiveTexture (gl_mtex_enum + 0);
qfglBindTexture (GL_TEXTURE_2D, tex->gl_texturenum);
R_RenderBrushPoly_2 (psurf);
qglActiveTexture (gl_mtex_enum + 1);
qfglDisable (GL_TEXTURE_2D);
qglActiveTexture (gl_mtex_enum + 0);
}
} else {
qfglBindTexture (GL_TEXTURE_2D, tex->gl_texturenum);
R_RenderBrushPoly_1 (psurf);
if (tex->gl_fb_texturenum && gl_mtex_fullbright) {
psurf->polys->fb_chain =
fullbright_polys[tex->gl_fb_texturenum];
fullbright_polys[tex->gl_fb_texturenum] = psurf->polys;
}
}
}
}
}
if (gl_mtex_active_tmus >= 2) {
qfglTexEnvf (GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
} else {
R_CalcAndBlendLightmaps ();
}
if (gl_fb_bmodels->int_val && !gl_mtex_fullbright)
R_RenderFullbrights ();
qfglPopMatrix ();
if (color[3] < 1.0)
qfglDepthMask (GL_TRUE);
qfglColor3ubv (color_white);
}
// WORLD MODEL ================================================================
static inline void
visit_leaf (mleaf_t *leaf)
{
// deal with model fragments in this leaf
if (leaf->efrags)
R_StoreEfrags (leaf->efrags);
}
static inline int
get_side (mnode_t *node)
{
// find which side of the node we are on
mplane_t *plane = node->plane;
if (plane->type < 3)
return (modelorg[plane->type] - plane->dist) < 0;
return (DotProduct (modelorg, plane->normal) - plane->dist) < 0;
}
static inline void
visit_node (mnode_t *node, int side)
{
int c;
msurface_t *surf;
// sneaky hack for side = side ? SURF_PLANEBACK : 0;
side = (~side + 1) & SURF_PLANEBACK;
// draw stuff
if ((c = node->numsurfaces)) {
surf = r_worldentity.model->surfaces + node->firstsurface;
for (; c; c--, surf++) {
if (surf->visframe != r_visframecount)
continue;
// side is either 0 or SURF_PLANEBACK
if (side ^ (surf->flags & SURF_PLANEBACK))
continue; // wrong side
if (surf->flags & SURF_DRAWTURB) {
CHAIN_SURF_B2F (surf, waterchain);
} else if (surf->flags & SURF_DRAWSKY) {
CHAIN_SURF_F2B (surf, sky_chain);
} else {
texture_t *tex;
R_AddToLightmapChain (surf);
if (!surf->texinfo->texture->anim_total)
tex = surf->texinfo->texture;
else
tex = R_TextureAnimation (surf);
if (gl_fb_bmodels->int_val && tex->gl_fb_texturenum
&& !gl_mtex_fullbright) {
surf->polys->fb_chain =
fullbright_polys[tex->gl_fb_texturenum];
fullbright_polys[tex->gl_fb_texturenum] = surf->polys;
}
CHAIN_SURF_F2B (surf, tex->texturechain);
}
}
}
}
static inline int
test_node (mnode_t *node)
{
if (node->contents < 0)
return 0;
if (node->visframe != r_visframecount)
return 0;
if (R_CullBox (node->minmaxs, node->minmaxs + 3))
return 0;
return 1;
}
// FIXME: R_IterativeWorldNode
static void
R_RecursiveWorldNode (mnode_t *node)
{
#define NODE_STACK 1024
struct {
mnode_t *node;
int side;
} *node_ptr, node_stack[NODE_STACK];
mnode_t *front;
int side;
node_ptr = node_stack;
while (1) {
while (test_node (node)) {
side = get_side (node);
front = node->children[side];
if (test_node (front)) {
if (node_ptr - node_stack == NODE_STACK)
Sys_Error ("node_stack overflow");
node_ptr->node = node;
node_ptr->side = side;
node_ptr++;
node = front;
continue;
}
if (front->contents < 0 && front->contents != CONTENTS_SOLID)
visit_leaf ((mleaf_t *) front);
visit_node (node, side);
node = node->children[!side];
}
if (node->contents < 0 && node->contents != CONTENTS_SOLID)
visit_leaf ((mleaf_t *) node);
if (node_ptr != node_stack) {
node_ptr--;
node = node_ptr->node;
side = node_ptr->side;
visit_node (node, side);
node = node->children[!side];
continue;
}
break;
}
if (node->contents < 0 && node->contents != CONTENTS_SOLID)
visit_leaf ((mleaf_t *) node);
}
void
R_DrawWorld (void)
{
entity_t ent;
memset (&ent, 0, sizeof (ent));
ent.model = r_worldentity.model;
VectorCopy (r_refdef.vieworg, modelorg);
currententity = &ent;
memset (lightmap_polys, 0, sizeof (lightmap_polys));
memset (fullbright_polys, 0, sizeof (fullbright_polys));
sky_chain = 0;
sky_chain_tail = &sky_chain;
if (!gl_sky_clip->int_val) {
R_DrawSky ();
}
R_RecursiveWorldNode (r_worldentity.model->nodes);
R_CalcLightmaps ();
R_DrawSkyChain (sky_chain);
DrawTextureChains ();
if (gl_mtex_active_tmus <= 1)
R_BlendLightmaps ();
if (gl_fb_bmodels->int_val && !gl_mtex_fullbright)
R_RenderFullbrights ();
}
void
R_MarkLeaves (void)
{
byte solid[4096];
byte *vis;
int c;
unsigned int i;
mleaf_t *leaf;
mnode_t *node;
msurface_t **mark;
if (r_oldviewleaf == r_viewleaf && !r_novis->int_val)
return;
r_visframecount++;
r_oldviewleaf = r_viewleaf;
if (r_novis->int_val) {
vis = solid;
memset (solid, 0xff, (r_worldentity.model->numleafs + 7) >> 3);
} else
vis = Mod_LeafPVS (r_viewleaf, r_worldentity.model);
for (i = 0; (int) i < r_worldentity.model->numleafs; i++) {
if (vis[i >> 3] & (1 << (i & 7))) {
leaf = &r_worldentity.model->leafs[i + 1];
if ((c = leaf->nummarksurfaces)) {
mark = leaf->firstmarksurface;
do {
(*mark)->visframe = r_visframecount;
mark++;
} while (--c);
}
node = (mnode_t *) leaf;
do {
if (node->visframe == r_visframecount)
break;
node->visframe = r_visframecount;
node = node->parent;
} while (node);
}
}
}
int nColinElim;
model_t *currentmodel;
mvertex_t *r_pcurrentvertbase;
void
BuildSurfaceDisplayList (msurface_t *fa)
{
float s, t;
float *vec;
int lindex, lnumverts, vertpage, i;
glpoly_t *poly;
medge_t *pedges, *r_pedge;
// reconstruct the polygon
pedges = currentmodel->edges;
lnumverts = fa->numedges;
vertpage = 0;
// draw texture
poly = Hunk_Alloc (sizeof (glpoly_t) + (lnumverts - 4) *
VERTEXSIZE * sizeof (float));
poly->next = fa->polys;
poly->flags = fa->flags;
fa->polys = poly;
poly->numverts = lnumverts;
for (i = 0; i < lnumverts; i++) {
lindex = currentmodel->surfedges[fa->firstedge + i];
if (lindex > 0) {
r_pedge = &pedges[lindex];
vec = r_pcurrentvertbase[r_pedge->v[0]].position;
} else {
r_pedge = &pedges[-lindex];
vec = r_pcurrentvertbase[r_pedge->v[1]].position;
}
s = DotProduct (vec, fa->texinfo->vecs[0]) + fa->texinfo->vecs[0][3];
s /= fa->texinfo->texture->width;
t = DotProduct (vec, fa->texinfo->vecs[1]) + fa->texinfo->vecs[1][3];
t /= fa->texinfo->texture->height;
VectorCopy (vec, poly->verts[i]);
poly->verts[i][3] = s;
poly->verts[i][4] = t;
// lightmap texture coordinates
s = DotProduct (vec, fa->texinfo->vecs[0]) + fa->texinfo->vecs[0][3];
s -= fa->texturemins[0];
s += fa->light_s * 16;
s += 8;
s /= BLOCK_WIDTH * 16; // fa->texinfo->texture->width;
t = DotProduct (vec, fa->texinfo->vecs[1]) + fa->texinfo->vecs[1][3];
t -= fa->texturemins[1];
t += fa->light_t * 16;
t += 8;
t /= BLOCK_HEIGHT * 16; // fa->texinfo->texture->height;
poly->verts[i][5] = s;
poly->verts[i][6] = t;
}
// remove co-linear points - Ed
if (!gl_keeptjunctions->int_val && !(fa->flags & SURF_UNDERWATER)) {
for (i = 0; i < lnumverts; ++i) {
vec3_t v1, v2;
float *prev, *this, *next;
prev = poly->verts[(i + lnumverts - 1) % lnumverts];
this = poly->verts[i];
next = poly->verts[(i + 1) % lnumverts];
VectorSubtract (this, prev, v1);
VectorNormalize (v1);
VectorSubtract (next, prev, v2);
VectorNormalize (v2);
// skip co-linear points
# define COLINEAR_EPSILON 0.001
if ((fabs (v1[0] - v2[0]) <= COLINEAR_EPSILON) &&
(fabs (v1[1] - v2[1]) <= COLINEAR_EPSILON) &&
(fabs (v1[2] - v2[2]) <= COLINEAR_EPSILON)) {
int j;
for (j = i + 1; j < lnumverts; ++j) {
int k;
for (k = 0; k < VERTEXSIZE; ++k)
poly->verts[j - 1][k] = poly->verts[j][k];
}
--lnumverts;
++nColinElim;
// retry next vertex next time, which is now current vertex
--i;
}
}
}
poly->numverts = lnumverts;
}