/*
gl_mesh.c
gl_mesh.c: triangle model functions
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_mesh.c,v 1.1.1.1 2001/03/06 09:33:19 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 <stdio.h>
#include "console.h"
#include "mdfour.h"
#include "model.h"
#include "quakefs.h"
/*
ALIAS MODEL DISPLAY LIST GENERATION
*/
model_t *aliasmodel;
aliashdr_t *paliashdr;
qboolean used[8192];
// the command list holds counts and s/t values that are valid for
// every frame
int commands[8192];
int numcommands;
// all frames will have their vertexes rearranged and expanded
// so they are in the order expected by the command list
int vertexorder[8192];
int numorder;
int allverts, alltris;
int stripverts[128];
int striptris[128];
int stripcount;
/*
StripLength
*/
int
StripLength (int starttri, int startv)
{
int m1, m2;
int j;
mtriangle_t *last, *check;
int k;
used[starttri] = 2;
last = &triangles[starttri];
stripverts[0] = last->vertindex[(startv) % 3];
stripverts[1] = last->vertindex[(startv + 1) % 3];
stripverts[2] = last->vertindex[(startv + 2) % 3];
striptris[0] = starttri;
stripcount = 1;
m1 = last->vertindex[(startv + 2) % 3];
m2 = last->vertindex[(startv + 1) % 3];
// look for a matching triangle
nexttri:
for (j = starttri + 1, check = &triangles[starttri + 1];
j < pheader->mdl.numtris; j++, check++) {
if (check->facesfront != last->facesfront)
continue;
for (k = 0; k < 3; k++) {
if (check->vertindex[k] != m1)
continue;
if (check->vertindex[(k + 1) % 3] != m2)
continue;
// this is the next part of the fan
// if we can't use this triangle, this tristrip is done
if (used[j])
goto done;
// the new edge
if (stripcount & 1)
m2 = check->vertindex[(k + 2) % 3];
else
m1 = check->vertindex[(k + 2) % 3];
stripverts[stripcount + 2] = check->vertindex[(k + 2) % 3];
striptris[stripcount] = j;
stripcount++;
used[j] = 2;
goto nexttri;
}
}
done:
// clear the temp used flags
for (j = starttri + 1; j < pheader->mdl.numtris; j++)
if (used[j] == 2)
used[j] = 0;
return stripcount;
}
/*
FanLength
*/
int
FanLength (int starttri, int startv)
{
int m1, m2;
int j;
mtriangle_t *last, *check;
int k;
used[starttri] = 2;
last = &triangles[starttri];
stripverts[0] = last->vertindex[(startv) % 3];
stripverts[1] = last->vertindex[(startv + 1) % 3];
stripverts[2] = last->vertindex[(startv + 2) % 3];
striptris[0] = starttri;
stripcount = 1;
m1 = last->vertindex[(startv + 0) % 3];
m2 = last->vertindex[(startv + 2) % 3];
// look for a matching triangle
nexttri:
for (j = starttri + 1, check = &triangles[starttri + 1];
j < pheader->mdl.numtris; j++, check++) {
if (check->facesfront != last->facesfront)
continue;
for (k = 0; k < 3; k++) {
if (check->vertindex[k] != m1)
continue;
if (check->vertindex[(k + 1) % 3] != m2)
continue;
// this is the next part of the fan
// if we can't use this triangle, this tristrip is done
if (used[j])
goto done;
// the new edge
m2 = check->vertindex[(k + 2) % 3];
stripverts[stripcount + 2] = m2;
striptris[stripcount] = j;
stripcount++;
used[j] = 2;
goto nexttri;
}
}
done:
// clear the temp used flags
for (j = starttri + 1; j < pheader->mdl.numtris; j++)
if (used[j] == 2)
used[j] = 0;
return stripcount;
}
/*
BuildTris
Generate a list of trifans or strips
for the model, which holds for all frames
*/
void
BuildTris (void)
{
int i, j, k;
int startv;
float s, t;
int len, bestlen, besttype = 0;
int bestverts[1024];
int besttris[1024];
int type;
//
// build tristrips
//
numorder = 0;
numcommands = 0;
memset (used, 0, sizeof (used));
for (i = 0; i < pheader->mdl.numtris; i++) {
// pick an unused triangle and start the trifan
if (used[i])
continue;
bestlen = 0;
for (type = 0; type < 2; type++)
// type = 1;
{
for (startv = 0; startv < 3; startv++) {
if (type == 1)
len = StripLength (i, startv);
else
len = FanLength (i, startv);
if (len > bestlen) {
besttype = type;
bestlen = len;
for (j = 0; j < bestlen + 2; j++)
bestverts[j] = stripverts[j];
for (j = 0; j < bestlen; j++)
besttris[j] = striptris[j];
}
}
}
// mark the tris on the best strip as used
for (j = 0; j < bestlen; j++)
used[besttris[j]] = 1;
if (besttype == 1)
commands[numcommands++] = (bestlen + 2);
else
commands[numcommands++] = -(bestlen + 2);
for (j = 0; j < bestlen + 2; j++) {
// emit a vertex into the reorder buffer
k = bestverts[j];
vertexorder[numorder++] = k;
// emit s/t coords into the commands stream
s = stverts[k].s;
t = stverts[k].t;
if (!triangles[besttris[0]].facesfront && stverts[k].onseam)
s += pheader->mdl.skinwidth / 2; // on back side
s = (s + 0.5) / pheader->mdl.skinwidth;
t = (t + 0.5) / pheader->mdl.skinheight;
*(float *) &commands[numcommands++] = s;
*(float *) &commands[numcommands++] = t;
}
}
commands[numcommands++] = 0; // end of list marker
Con_DPrintf ("%3i tri %3i vert %3i cmd\n", pheader->mdl.numtris, numorder,
numcommands);
allverts += numorder;
alltris += pheader->mdl.numtris;
}
/*
GL_MakeAliasModelDisplayLists
*/
void
GL_MakeAliasModelDisplayLists (model_t *m, aliashdr_t *hdr, void *_m, int _s)
{
int i, j;
int *cmds;
trivertx_t *verts;
char cache[MAX_QPATH], fullpath[MAX_OSPATH];
QFile *f;
unsigned char model_digest[MDFOUR_DIGEST_BYTES];
unsigned char mesh_digest[MDFOUR_DIGEST_BYTES];
qboolean remesh = true;
aliasmodel = m;
paliashdr = hdr; // (aliashdr_t *)Mod_Extradata (m);
mdfour (model_digest, (unsigned char*)_m, _s);
//
// look for a cached version
//
strcpy (cache, "glquake/");
COM_StripExtension (m->name + strlen ("progs/"),
cache + strlen ("glquake/"));
strncat (cache, ".ms2", sizeof (cache) - strlen (cache));
COM_FOpenFile (cache, &f);
if (f) {
unsigned char d1[MDFOUR_DIGEST_BYTES];
unsigned char d2[MDFOUR_DIGEST_BYTES];
struct mdfour md;
int c[8192];
int nc;
int vo[8192];
int no;
memset (d1, 0, sizeof (d1));
memset (d2, 0, sizeof (d2));
Qread (f, &nc, 4);
Qread (f, &no, 4);
if (nc <= 8192 && no <= 8192) {
Qread (f, &c, nc * sizeof (c[0]));
Qread (f, &vo, no * sizeof (vo[0]));
Qread (f, d1, MDFOUR_DIGEST_BYTES);
Qread (f, d2, MDFOUR_DIGEST_BYTES);
Qclose (f);
mdfour_begin (&md);
mdfour_update (&md, (unsigned char*)&nc, 4);
mdfour_update (&md, (unsigned char*)&no, 4);
mdfour_update (&md, (unsigned char*)&c, nc * sizeof (c[0]));
mdfour_update (&md, (unsigned char*)&vo, no * sizeof (vo[0]));
mdfour_update (&md, d1, MDFOUR_DIGEST_BYTES);
mdfour_result (&md, mesh_digest);
if (memcmp (d2, mesh_digest, MDFOUR_DIGEST_BYTES) == 0 && memcmp (d1, model_digest, MDFOUR_DIGEST_BYTES) == 0) {
remesh = false;
numcommands = nc;
numorder = no;
memcpy (commands, c, numcommands * sizeof (c[0]));
memcpy (vertexorder, vo, numorder * sizeof (vo[0]));
}
}
}
if (remesh) {
//
// build it from scratch
//
Con_Printf ("meshing %s...\n", m->name);
BuildTris (); // trifans or lists
//
// save out the cached version
//
snprintf (fullpath, sizeof (fullpath), "%s/%s", com_gamedir, cache);
f = Qopen (fullpath, "wbz9");
if (!f) {
COM_CreatePath (fullpath);
f = Qopen (fullpath, "wb");
}
if (f) {
struct mdfour md;
mdfour_begin (&md);
mdfour_update (&md, (unsigned char*)&numcommands, 4);
mdfour_update (&md, (unsigned char*)&numorder, 4);
mdfour_update (&md, (unsigned char*)&commands, numcommands * sizeof (commands[0]));
mdfour_update (&md, (unsigned char*)&vertexorder,
numorder * sizeof (vertexorder[0]));
mdfour_update (&md, model_digest, MDFOUR_DIGEST_BYTES);
mdfour_result (&md, mesh_digest);
Qwrite (f, &numcommands, 4);
Qwrite (f, &numorder, 4);
Qwrite (f, &commands, numcommands * sizeof (commands[0]));
Qwrite (f, &vertexorder, numorder * sizeof (vertexorder[0]));
Qwrite (f, model_digest, MDFOUR_DIGEST_BYTES);
Qwrite (f, mesh_digest, MDFOUR_DIGEST_BYTES);
Qclose (f);
}
}
// save the data out
paliashdr->poseverts = numorder;
cmds = Hunk_Alloc (numcommands * 4);
paliashdr->commands = (byte *) cmds - (byte *) paliashdr;
memcpy (cmds, commands, numcommands * 4);
verts = Hunk_Alloc (paliashdr->numposes * paliashdr->poseverts
* sizeof (trivertx_t));
paliashdr->posedata = (byte *) verts - (byte *) paliashdr;
for (i = 0; i < paliashdr->numposes; i++)
for (j = 0; j < numorder; j++)
*verts++ = poseverts[i][vertexorder[j]];
}