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halflife-sdk-steam/utils/studiomdl/tristrip.c

353 lines
6.7 KiB
C

/***
*
* Copyright (c) 1996-2002, Valve LLC. All rights reserved.
*
* This product contains software technology licensed from Id
* Software, Inc. ("Id Technology"). Id Technology (c) 1996 Id Software, Inc.
* All Rights Reserved.
*
****/
// tristrip - convert triangle list into tristrips and fans
#pragma warning( disable : 4244 )
#pragma warning( disable : 4237 )
#pragma warning( disable : 4305 )
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include "archtypes.h"
#include "cmdlib.h"
#include "lbmlib.h"
#include "scriplib.h"
#include "mathlib.h"
#include "..\..\engine\studio.h"
#include "studiomdl.h"
int used[MAXSTUDIOTRIANGLES];
// the command list holds counts and s/t values that are valid for
// every frame
short commands[MAXSTUDIOTRIANGLES * 13];
int numcommands;
// all frames will have their vertexes rearranged and expanded
// so they are in the order expected by the command list
int allverts, alltris;
int stripverts[MAXSTUDIOTRIANGLES+2];
int striptris[MAXSTUDIOTRIANGLES+2];
int stripcount;
int neighbortri[MAXSTUDIOTRIANGLES][3];
int neighboredge[MAXSTUDIOTRIANGLES][3];
s_trianglevert_t (*triangles)[3];
s_mesh_t *pmesh;
void FindNeighbor (int starttri, int startv)
{
s_trianglevert_t m1, m2;
int j;
s_trianglevert_t *last, *check;
int k;
// used[starttri] |= (1 << startv);
last = &triangles[starttri][0];
m1 = last[(startv+1)%3];
m2 = last[(startv+0)%3];
for (j=starttri+1, check=&triangles[starttri+1][0] ; j<pmesh->numtris ; j++, check += 3)
{
if (used[j] == 7)
continue;
for (k=0 ; k<3 ; k++)
{
if (memcmp(&check[k],&m1,sizeof(m1)))
continue;
if (memcmp(&check[ (k+1)%3 ],&m2,sizeof(m2)))
continue;
neighbortri[starttri][startv] = j;
neighboredge[starttri][startv] = k;
neighbortri[j][k] = starttri;
neighboredge[j][k] = startv;
used[starttri] |= (1 << startv);
used[j] |= (1 << k);
return;
}
}
}
/*
================
StripLength
================
*/
int StripLength (int starttri, int startv)
{
int j;
int k;
used[starttri] = 2;
stripverts[0] = (startv)%3;
stripverts[1] = (startv+1)%3;
stripverts[2] = (startv+2)%3;
striptris[0] = starttri;
striptris[1] = starttri;
striptris[2] = starttri;
stripcount = 3;
while( 1 )
{
if (stripcount & 1)
{
j = neighbortri[starttri][(startv+1)%3];
k = neighboredge[starttri][(startv+1)%3];
}
else
{
j = neighbortri[starttri][(startv+2)%3];
k = neighboredge[starttri][(startv+2)%3];
}
if (j == -1 || used[j])
goto done;
stripverts[stripcount] = (k+2)%3;
striptris[stripcount] = j;
stripcount++;
used[j] = 2;
starttri = j;
startv = k;
}
done:
// clear the temp used flags
for (j=0 ; j<pmesh->numtris ; j++)
if (used[j] == 2)
used[j] = 0;
return stripcount;
}
/*
===========
FanLength
===========
*/
int FanLength (int starttri, int startv)
{
int j;
int k;
used[starttri] = 2;
stripverts[0] = (startv)%3;
stripverts[1] = (startv+1)%3;
stripverts[2] = (startv+2)%3;
striptris[0] = starttri;
striptris[1] = starttri;
striptris[2] = starttri;
stripcount = 3;
while( 1 )
{
j = neighbortri[starttri][(startv+2)%3];
k = neighboredge[starttri][(startv+2)%3];
if (j == -1 || used[j])
goto done;
stripverts[stripcount] = (k+2)%3;
striptris[stripcount] = j;
stripcount++;
used[j] = 2;
starttri = j;
startv = k;
}
done:
// clear the temp used flags
for (j=0 ; j<pmesh->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
================
*/
int numcommandnodes;
int BuildTris (s_trianglevert_t (*x)[3], s_mesh_t *y, byte **ppdata )
{
int i, j, k, m;
int startv;
int len, bestlen, besttype;
int bestverts[MAXSTUDIOTRIANGLES];
int besttris[MAXSTUDIOTRIANGLES];
int peak[MAXSTUDIOTRIANGLES];
int type;
int total = 0;
long t;
int maxlen;
triangles = x;
pmesh = y;
t = time( NULL );
for (i=0 ; i<pmesh->numtris ; i++)
{
neighbortri[i][0] = neighbortri[i][1] = neighbortri[i][2] = -1;
used[i] = 0;
peak[i] = pmesh->numtris;
}
// printf("finding neighbors\n");
for (i=0 ; i<pmesh->numtris; i++)
{
for (k = 0; k < 3; k++)
{
if (used[i] & (1 << k))
continue;
FindNeighbor( i, k );
}
// printf("%d", used[i] );
}
// printf("\n");
//
// build tristrips
//
numcommandnodes = 0;
numcommands = 0;
memset (used, 0, sizeof(used));
for (i=0 ; i<pmesh->numtris ;)
{
// pick an unused triangle and start the trifan
if (used[i])
{
i++;
continue;
}
maxlen = 9999;
bestlen = 0;
m = 0;
for (k = i; k < pmesh->numtris && bestlen < 127; k++)
{
int localpeak = 0;
if (used[k])
continue;
if (peak[k] <= bestlen)
continue;
m++;
for (type = 0 ; type < 2 ; type++)
{
for (startv =0 ; startv < 3 ; startv++)
{
if (type == 1)
len = FanLength (k, startv);
else
len = StripLength (k, startv);
if (len > 127)
{
// skip these, they are too long to encode
}
else if (len > bestlen)
{
besttype = type;
bestlen = len;
for (j=0 ; j<bestlen ; j++)
{
besttris[j] = striptris[j];
bestverts[j] = stripverts[j];
}
// printf("%d %d\n", k, bestlen );
}
if (len > localpeak)
localpeak = len;
}
}
peak[k] = localpeak;
if (localpeak == maxlen)
break;
}
total += (bestlen - 2);
// printf("%d (%d) %d\n", bestlen, pmesh->numtris - total, i );
maxlen = bestlen;
// 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;
else
commands[numcommands++] = bestlen;
for (j=0 ; j<bestlen ; j++)
{
s_trianglevert_t *tri;
tri = &triangles[besttris[j]][bestverts[j]];
commands[numcommands++] = tri->vertindex;
commands[numcommands++] = tri->normindex;
commands[numcommands++] = tri->s;
commands[numcommands++] = tri->t;
}
// printf("%d ", bestlen - 2 );
numcommandnodes++;
if (t != time(NULL))
{
printf("%2d%%\r", (total * 100) / pmesh->numtris );
t = time(NULL);
}
}
commands[numcommands++] = 0; // end of list marker
*ppdata = (byte *)commands;
// printf("%d %d %d\n", numcommandnodes, numcommands, pmesh->numtris );
return numcommands * sizeof( short );
}