blender/intern/mikktspace/mikktspace.c
Campbell Barton 0392acc607 fix [#36685] crash calculating tangent space data on degenerate geometry
the error was that the range check was done on the float before converting to an int.
now convert to and int first and ensure a valid range on that.
2013-09-09 09:33:34 +00:00

1891 lines
56 KiB
C

/** \file mikktspace/mikktspace.c
* \ingroup mikktspace
*/
/**
* Copyright (C) 2011 by Morten S. Mikkelsen
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
#include <assert.h>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include <float.h>
#include <stdlib.h>
#include "mikktspace.h"
#define TFALSE 0
#define TTRUE 1
#ifndef M_PI
#define M_PI 3.1415926535897932384626433832795
#endif
#define INTERNAL_RND_SORT_SEED 39871946
// internal structure
typedef struct {
float x, y, z;
} SVec3;
static tbool veq( const SVec3 v1, const SVec3 v2 )
{
return (v1.x == v2.x) && (v1.y == v2.y) && (v1.z == v2.z);
}
static SVec3 vadd( const SVec3 v1, const SVec3 v2 )
{
SVec3 vRes;
vRes.x = v1.x + v2.x;
vRes.y = v1.y + v2.y;
vRes.z = v1.z + v2.z;
return vRes;
}
static SVec3 vsub( const SVec3 v1, const SVec3 v2 )
{
SVec3 vRes;
vRes.x = v1.x - v2.x;
vRes.y = v1.y - v2.y;
vRes.z = v1.z - v2.z;
return vRes;
}
static SVec3 vscale(const float fS, const SVec3 v)
{
SVec3 vRes;
vRes.x = fS * v.x;
vRes.y = fS * v.y;
vRes.z = fS * v.z;
return vRes;
}
static float LengthSquared( const SVec3 v )
{
return v.x*v.x + v.y*v.y + v.z*v.z;
}
static float Length( const SVec3 v )
{
return sqrtf(LengthSquared(v));
}
static SVec3 Normalize( const SVec3 v )
{
return vscale(1 / Length(v), v);
}
static float vdot( const SVec3 v1, const SVec3 v2)
{
return v1.x*v2.x + v1.y*v2.y + v1.z*v2.z;
}
static tbool NotZero(const float fX)
{
// could possibly use FLT_EPSILON instead
return fabsf(fX) > FLT_MIN;
}
static tbool VNotZero(const SVec3 v)
{
// might change this to an epsilon based test
return NotZero(v.x) || NotZero(v.y) || NotZero(v.z);
}
typedef struct {
int iNrFaces;
int * pTriMembers;
} SSubGroup;
typedef struct {
int iNrFaces;
int * pFaceIndices;
int iVertexRepresentitive;
tbool bOrientPreservering;
} SGroup;
//
#define MARK_DEGENERATE 1
#define QUAD_ONE_DEGEN_TRI 2
#define GROUP_WITH_ANY 4
#define ORIENT_PRESERVING 8
typedef struct {
int FaceNeighbors[3];
SGroup * AssignedGroup[3];
// normalized first order face derivatives
SVec3 vOs, vOt;
float fMagS, fMagT; // original magnitudes
// determines if the current and the next triangle are a quad.
int iOrgFaceNumber;
int iFlag, iTSpacesOffs;
unsigned char vert_num[4];
} STriInfo;
typedef struct {
SVec3 vOs;
float fMagS;
SVec3 vOt;
float fMagT;
int iCounter; // this is to average back into quads.
tbool bOrient;
} STSpace;
static int GenerateInitialVerticesIndexList(STriInfo pTriInfos[], int piTriList_out[], const SMikkTSpaceContext * pContext, const int iNrTrianglesIn);
static void GenerateSharedVerticesIndexList(int piTriList_in_and_out[], const SMikkTSpaceContext * pContext, const int iNrTrianglesIn);
static void InitTriInfo(STriInfo pTriInfos[], const int piTriListIn[], const SMikkTSpaceContext * pContext, const int iNrTrianglesIn);
static int Build4RuleGroups(STriInfo pTriInfos[], SGroup pGroups[], int piGroupTrianglesBuffer[], const int piTriListIn[], const int iNrTrianglesIn);
static tbool GenerateTSpaces(STSpace psTspace[], const STriInfo pTriInfos[], const SGroup pGroups[],
const int iNrActiveGroups, const int piTriListIn[], const float fThresCos,
const SMikkTSpaceContext * pContext);
static int MakeIndex(const int iFace, const int iVert)
{
assert(iVert>=0 && iVert<4 && iFace>=0);
return (iFace<<2) | (iVert&0x3);
}
static void IndexToData(int * piFace, int * piVert, const int iIndexIn)
{
piVert[0] = iIndexIn&0x3;
piFace[0] = iIndexIn>>2;
}
static STSpace AvgTSpace(const STSpace * pTS0, const STSpace * pTS1)
{
STSpace ts_res;
// this if is important. Due to floating point precision
// averaging when ts0==ts1 will cause a slight difference
// which results in tangent space splits later on
if (pTS0->fMagS==pTS1->fMagS && pTS0->fMagT==pTS1->fMagT &&
veq(pTS0->vOs,pTS1->vOs) && veq(pTS0->vOt, pTS1->vOt))
{
ts_res.fMagS = pTS0->fMagS;
ts_res.fMagT = pTS0->fMagT;
ts_res.vOs = pTS0->vOs;
ts_res.vOt = pTS0->vOt;
}
else
{
ts_res.fMagS = 0.5f*(pTS0->fMagS+pTS1->fMagS);
ts_res.fMagT = 0.5f*(pTS0->fMagT+pTS1->fMagT);
ts_res.vOs = vadd(pTS0->vOs,pTS1->vOs);
ts_res.vOt = vadd(pTS0->vOt,pTS1->vOt);
if ( VNotZero(ts_res.vOs) ) ts_res.vOs = Normalize(ts_res.vOs);
if ( VNotZero(ts_res.vOt) ) ts_res.vOt = Normalize(ts_res.vOt);
}
return ts_res;
}
static SVec3 GetPosition(const SMikkTSpaceContext * pContext, const int index);
static SVec3 GetNormal(const SMikkTSpaceContext * pContext, const int index);
static SVec3 GetTexCoord(const SMikkTSpaceContext * pContext, const int index);
// degen triangles
static void DegenPrologue(STriInfo pTriInfos[], int piTriList_out[], const int iNrTrianglesIn, const int iTotTris);
static void DegenEpilogue(STSpace psTspace[], STriInfo pTriInfos[], int piTriListIn[], const SMikkTSpaceContext * pContext, const int iNrTrianglesIn, const int iTotTris);
tbool genTangSpaceDefault(const SMikkTSpaceContext * pContext)
{
return genTangSpace(pContext, 180.0f);
}
tbool genTangSpace(const SMikkTSpaceContext * pContext, const float fAngularThreshold)
{
// count nr_triangles
int * piTriListIn = NULL, * piGroupTrianglesBuffer = NULL;
STriInfo * pTriInfos = NULL;
SGroup * pGroups = NULL;
STSpace * psTspace = NULL;
int iNrTrianglesIn = 0, f=0, t=0, i=0;
int iNrTSPaces = 0, iTotTris = 0, iDegenTriangles = 0, iNrMaxGroups = 0;
int iNrActiveGroups = 0, index = 0;
const int iNrFaces = pContext->m_pInterface->m_getNumFaces(pContext);
tbool bRes = TFALSE;
const float fThresCos = (float) cos((fAngularThreshold*(float)M_PI)/180.0f);
// verify all call-backs have been set
if ( pContext->m_pInterface->m_getNumFaces==NULL ||
pContext->m_pInterface->m_getNumVerticesOfFace==NULL ||
pContext->m_pInterface->m_getPosition==NULL ||
pContext->m_pInterface->m_getNormal==NULL ||
pContext->m_pInterface->m_getTexCoord==NULL )
return TFALSE;
// count triangles on supported faces
for (f=0; f<iNrFaces; f++)
{
const int verts = pContext->m_pInterface->m_getNumVerticesOfFace(pContext, f);
if (verts==3) ++iNrTrianglesIn;
else if (verts==4) iNrTrianglesIn += 2;
}
if (iNrTrianglesIn<=0) return TFALSE;
// allocate memory for an index list
piTriListIn = (int *) malloc(sizeof(int)*3*iNrTrianglesIn);
pTriInfos = (STriInfo *) malloc(sizeof(STriInfo)*iNrTrianglesIn);
if (piTriListIn==NULL || pTriInfos==NULL)
{
if (piTriListIn!=NULL) free(piTriListIn);
if (pTriInfos!=NULL) free(pTriInfos);
return TFALSE;
}
// make an initial triangle --> face index list
iNrTSPaces = GenerateInitialVerticesIndexList(pTriInfos, piTriListIn, pContext, iNrTrianglesIn);
// make a welded index list of identical positions and attributes (pos, norm, texc)
//printf("gen welded index list begin\n");
GenerateSharedVerticesIndexList(piTriListIn, pContext, iNrTrianglesIn);
//printf("gen welded index list end\n");
// Mark all degenerate triangles
iTotTris = iNrTrianglesIn;
iDegenTriangles = 0;
for (t=0; t<iTotTris; t++)
{
const int i0 = piTriListIn[t*3+0];
const int i1 = piTriListIn[t*3+1];
const int i2 = piTriListIn[t*3+2];
const SVec3 p0 = GetPosition(pContext, i0);
const SVec3 p1 = GetPosition(pContext, i1);
const SVec3 p2 = GetPosition(pContext, i2);
if (veq(p0,p1) || veq(p0,p2) || veq(p1,p2)) // degenerate
{
pTriInfos[t].iFlag |= MARK_DEGENERATE;
++iDegenTriangles;
}
}
iNrTrianglesIn = iTotTris - iDegenTriangles;
// mark all triangle pairs that belong to a quad with only one
// good triangle. These need special treatment in DegenEpilogue().
// Additionally, move all good triangles to the start of
// pTriInfos[] and piTriListIn[] without changing order and
// put the degenerate triangles last.
DegenPrologue(pTriInfos, piTriListIn, iNrTrianglesIn, iTotTris);
// evaluate triangle level attributes and neighbor list
//printf("gen neighbors list begin\n");
InitTriInfo(pTriInfos, piTriListIn, pContext, iNrTrianglesIn);
//printf("gen neighbors list end\n");
// based on the 4 rules, identify groups based on connectivity
iNrMaxGroups = iNrTrianglesIn*3;
pGroups = (SGroup *) malloc(sizeof(SGroup)*iNrMaxGroups);
piGroupTrianglesBuffer = (int *) malloc(sizeof(int)*iNrTrianglesIn*3);
if (pGroups==NULL || piGroupTrianglesBuffer==NULL)
{
if (pGroups!=NULL) free(pGroups);
if (piGroupTrianglesBuffer!=NULL) free(piGroupTrianglesBuffer);
free(piTriListIn);
free(pTriInfos);
return TFALSE;
}
//printf("gen 4rule groups begin\n");
iNrActiveGroups =
Build4RuleGroups(pTriInfos, pGroups, piGroupTrianglesBuffer, piTriListIn, iNrTrianglesIn);
//printf("gen 4rule groups end\n");
//
psTspace = (STSpace *) malloc(sizeof(STSpace)*iNrTSPaces);
if (psTspace==NULL)
{
free(piTriListIn);
free(pTriInfos);
free(pGroups);
free(piGroupTrianglesBuffer);
return TFALSE;
}
memset(psTspace, 0, sizeof(STSpace)*iNrTSPaces);
for (t=0; t<iNrTSPaces; t++)
{
psTspace[t].vOs.x=1.0f; psTspace[t].vOs.y=0.0f; psTspace[t].vOs.z=0.0f; psTspace[t].fMagS = 1.0f;
psTspace[t].vOt.x=0.0f; psTspace[t].vOt.y=1.0f; psTspace[t].vOt.z=0.0f; psTspace[t].fMagT = 1.0f;
}
// make tspaces, each group is split up into subgroups if necessary
// based on fAngularThreshold. Finally a tangent space is made for
// every resulting subgroup
//printf("gen tspaces begin\n");
bRes = GenerateTSpaces(psTspace, pTriInfos, pGroups, iNrActiveGroups, piTriListIn, fThresCos, pContext);
//printf("gen tspaces end\n");
// clean up
free(pGroups);
free(piGroupTrianglesBuffer);
if (!bRes) // if an allocation in GenerateTSpaces() failed
{
// clean up and return false
free(pTriInfos); free(piTriListIn); free(psTspace);
return TFALSE;
}
// degenerate quads with one good triangle will be fixed by copying a space from
// the good triangle to the coinciding vertex.
// all other degenerate triangles will just copy a space from any good triangle
// with the same welded index in piTriListIn[].
DegenEpilogue(psTspace, pTriInfos, piTriListIn, pContext, iNrTrianglesIn, iTotTris);
free(pTriInfos); free(piTriListIn);
index = 0;
for (f=0; f<iNrFaces; f++)
{
const int verts = pContext->m_pInterface->m_getNumVerticesOfFace(pContext, f);
if (verts!=3 && verts!=4) continue;
// I've decided to let degenerate triangles and group-with-anythings
// vary between left/right hand coordinate systems at the vertices.
// All healthy triangles on the other hand are built to always be either or.
/*// force the coordinate system orientation to be uniform for every face.
// (this is already the case for good triangles but not for
// degenerate ones and those with bGroupWithAnything==true)
bool bOrient = psTspace[index].bOrient;
if (psTspace[index].iCounter == 0) // tspace was not derived from a group
{
// look for a space created in GenerateTSpaces() by iCounter>0
bool bNotFound = true;
int i=1;
while (i<verts && bNotFound)
{
if (psTspace[index+i].iCounter > 0) bNotFound=false;
else ++i;
}
if (!bNotFound) bOrient = psTspace[index+i].bOrient;
}*/
// set data
for (i=0; i<verts; i++)
{
const STSpace * pTSpace = &psTspace[index];
float tang[] = {pTSpace->vOs.x, pTSpace->vOs.y, pTSpace->vOs.z};
float bitang[] = {pTSpace->vOt.x, pTSpace->vOt.y, pTSpace->vOt.z};
if (pContext->m_pInterface->m_setTSpace!=NULL)
pContext->m_pInterface->m_setTSpace(pContext, tang, bitang, pTSpace->fMagS, pTSpace->fMagT, pTSpace->bOrient, f, i);
if (pContext->m_pInterface->m_setTSpaceBasic!=NULL)
pContext->m_pInterface->m_setTSpaceBasic(pContext, tang, pTSpace->bOrient==TTRUE ? 1.0f : (-1.0f), f, i);
++index;
}
}
free(psTspace);
return TTRUE;
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////
typedef struct {
float vert[3];
int index;
} STmpVert;
static const int g_iCells = 2048;
#ifdef _MSC_VER
#define NOINLINE __declspec(noinline)
#else
#define NOINLINE __attribute__ ((noinline))
#endif
// it is IMPORTANT that this function is called to evaluate the hash since
// inlining could potentially reorder instructions and generate different
// results for the same effective input value fVal.
static NOINLINE int FindGridCell(const float fMin, const float fMax, const float fVal)
{
const float fIndex = g_iCells * ((fVal-fMin)/(fMax-fMin));
const int iIndex = (int)fIndex;
return iIndex < g_iCells ? (iIndex >= 0 ? iIndex : 0) : (g_iCells - 1);
}
static void MergeVertsFast(int piTriList_in_and_out[], STmpVert pTmpVert[], const SMikkTSpaceContext * pContext, const int iL_in, const int iR_in);
static void MergeVertsSlow(int piTriList_in_and_out[], const SMikkTSpaceContext * pContext, const int pTable[], const int iEntries);
static void GenerateSharedVerticesIndexListSlow(int piTriList_in_and_out[], const SMikkTSpaceContext * pContext, const int iNrTrianglesIn);
static void GenerateSharedVerticesIndexList(int piTriList_in_and_out[], const SMikkTSpaceContext * pContext, const int iNrTrianglesIn)
{
// Generate bounding box
int * piHashTable=NULL, * piHashCount=NULL, * piHashOffsets=NULL, * piHashCount2=NULL;
STmpVert * pTmpVert = NULL;
int i=0, iChannel=0, k=0, e=0;
int iMaxCount=0;
SVec3 vMin = GetPosition(pContext, 0), vMax = vMin, vDim;
float fMin, fMax;
for (i=1; i<(iNrTrianglesIn*3); i++)
{
const int index = piTriList_in_and_out[i];
const SVec3 vP = GetPosition(pContext, index);
if (vMin.x > vP.x) vMin.x = vP.x;
else if (vMax.x < vP.x) vMax.x = vP.x;
if (vMin.y > vP.y) vMin.y = vP.y;
else if (vMax.y < vP.y) vMax.y = vP.y;
if (vMin.z > vP.z) vMin.z = vP.z;
else if (vMax.z < vP.z) vMax.z = vP.z;
}
vDim = vsub(vMax,vMin);
iChannel = 0;
fMin = vMin.x; fMax=vMax.x;
if (vDim.y>vDim.x && vDim.y>vDim.z)
{
iChannel=1;
fMin = vMin.y, fMax=vMax.y;
}
else if (vDim.z>vDim.x)
{
iChannel=2;
fMin = vMin.z, fMax=vMax.z;
}
// make allocations
piHashTable = (int *) malloc(sizeof(int)*iNrTrianglesIn*3);
piHashCount = (int *) malloc(sizeof(int)*g_iCells);
piHashOffsets = (int *) malloc(sizeof(int)*g_iCells);
piHashCount2 = (int *) malloc(sizeof(int)*g_iCells);
if (piHashTable==NULL || piHashCount==NULL || piHashOffsets==NULL || piHashCount2==NULL)
{
if (piHashTable!=NULL) free(piHashTable);
if (piHashCount!=NULL) free(piHashCount);
if (piHashOffsets!=NULL) free(piHashOffsets);
if (piHashCount2!=NULL) free(piHashCount2);
GenerateSharedVerticesIndexListSlow(piTriList_in_and_out, pContext, iNrTrianglesIn);
return;
}
memset(piHashCount, 0, sizeof(int)*g_iCells);
memset(piHashCount2, 0, sizeof(int)*g_iCells);
// count amount of elements in each cell unit
for (i=0; i<(iNrTrianglesIn*3); i++)
{
const int index = piTriList_in_and_out[i];
const SVec3 vP = GetPosition(pContext, index);
const float fVal = iChannel==0 ? vP.x : (iChannel==1 ? vP.y : vP.z);
const int iCell = FindGridCell(fMin, fMax, fVal);
++piHashCount[iCell];
}
// evaluate start index of each cell.
piHashOffsets[0]=0;
for (k=1; k<g_iCells; k++)
piHashOffsets[k]=piHashOffsets[k-1]+piHashCount[k-1];
// insert vertices
for (i=0; i<(iNrTrianglesIn*3); i++)
{
const int index = piTriList_in_and_out[i];
const SVec3 vP = GetPosition(pContext, index);
const float fVal = iChannel==0 ? vP.x : (iChannel==1 ? vP.y : vP.z);
const int iCell = FindGridCell(fMin, fMax, fVal);
int * pTable = NULL;
assert(piHashCount2[iCell]<piHashCount[iCell]);
pTable = &piHashTable[piHashOffsets[iCell]];
pTable[piHashCount2[iCell]] = i; // vertex i has been inserted.
++piHashCount2[iCell];
}
for (k=0; k<g_iCells; k++)
assert(piHashCount2[k] == piHashCount[k]); // verify the count
free(piHashCount2);
// find maximum amount of entries in any hash entry
iMaxCount = piHashCount[0];
for (k=1; k<g_iCells; k++)
if (iMaxCount<piHashCount[k])
iMaxCount=piHashCount[k];
pTmpVert = (STmpVert *) malloc(sizeof(STmpVert)*iMaxCount);
// complete the merge
for (k=0; k<g_iCells; k++)
{
// extract table of cell k and amount of entries in it
int * pTable = &piHashTable[piHashOffsets[k]];
const int iEntries = piHashCount[k];
if (iEntries < 2) continue;
if (pTmpVert!=NULL)
{
for (e=0; e<iEntries; e++)
{
int i = pTable[e];
const SVec3 vP = GetPosition(pContext, piTriList_in_and_out[i]);
pTmpVert[e].vert[0] = vP.x; pTmpVert[e].vert[1] = vP.y;
pTmpVert[e].vert[2] = vP.z; pTmpVert[e].index = i;
}
MergeVertsFast(piTriList_in_and_out, pTmpVert, pContext, 0, iEntries-1);
}
else
MergeVertsSlow(piTriList_in_and_out, pContext, pTable, iEntries);
}
if (pTmpVert!=NULL) { free(pTmpVert); }
free(piHashTable);
free(piHashCount);
free(piHashOffsets);
}
static void MergeVertsFast(int piTriList_in_and_out[], STmpVert pTmpVert[], const SMikkTSpaceContext * pContext, const int iL_in, const int iR_in)
{
// make bbox
int c=0, l=0, channel=0;
float fvMin[3], fvMax[3];
float dx=0, dy=0, dz=0, fSep=0;
for (c=0; c<3; c++)
{ fvMin[c]=pTmpVert[iL_in].vert[c]; fvMax[c]=fvMin[c]; }
for (l=(iL_in+1); l<=iR_in; l++)
for (c=0; c<3; c++)
if (fvMin[c]>pTmpVert[l].vert[c]) fvMin[c]=pTmpVert[l].vert[c];
else if (fvMax[c]<pTmpVert[l].vert[c]) fvMax[c]=pTmpVert[l].vert[c];
dx = fvMax[0]-fvMin[0];
dy = fvMax[1]-fvMin[1];
dz = fvMax[2]-fvMin[2];
channel = 0;
if (dy>dx && dy>dz) channel=1;
else if (dz>dx) channel=2;
fSep = 0.5f*(fvMax[channel]+fvMin[channel]);
// terminate recursion when the separation/average value
// is no longer strictly between fMin and fMax values.
if (fSep>=fvMax[channel] || fSep<=fvMin[channel])
{
// complete the weld
for (l=iL_in; l<=iR_in; l++)
{
int i = pTmpVert[l].index;
const int index = piTriList_in_and_out[i];
const SVec3 vP = GetPosition(pContext, index);
const SVec3 vN = GetNormal(pContext, index);
const SVec3 vT = GetTexCoord(pContext, index);
tbool bNotFound = TTRUE;
int l2=iL_in, i2rec=-1;
while (l2<l && bNotFound)
{
const int i2 = pTmpVert[l2].index;
const int index2 = piTriList_in_and_out[i2];
const SVec3 vP2 = GetPosition(pContext, index2);
const SVec3 vN2 = GetNormal(pContext, index2);
const SVec3 vT2 = GetTexCoord(pContext, index2);
i2rec=i2;
//if (vP==vP2 && vN==vN2 && vT==vT2)
if (vP.x==vP2.x && vP.y==vP2.y && vP.z==vP2.z &&
vN.x==vN2.x && vN.y==vN2.y && vN.z==vN2.z &&
vT.x==vT2.x && vT.y==vT2.y && vT.z==vT2.z)
bNotFound = TFALSE;
else
++l2;
}
// merge if previously found
if (!bNotFound)
piTriList_in_and_out[i] = piTriList_in_and_out[i2rec];
}
}
else
{
int iL=iL_in, iR=iR_in;
assert((iR_in-iL_in)>0); // at least 2 entries
// separate (by fSep) all points between iL_in and iR_in in pTmpVert[]
while (iL < iR)
{
tbool bReadyLeftSwap = TFALSE, bReadyRightSwap = TFALSE;
while ((!bReadyLeftSwap) && iL<iR)
{
assert(iL>=iL_in && iL<=iR_in);
bReadyLeftSwap = !(pTmpVert[iL].vert[channel]<fSep);
if (!bReadyLeftSwap) ++iL;
}
while ((!bReadyRightSwap) && iL<iR)
{
assert(iR>=iL_in && iR<=iR_in);
bReadyRightSwap = pTmpVert[iR].vert[channel]<fSep;
if (!bReadyRightSwap) --iR;
}
assert( (iL<iR) || !(bReadyLeftSwap && bReadyRightSwap) );
if (bReadyLeftSwap && bReadyRightSwap)
{
const STmpVert sTmp = pTmpVert[iL];
assert(iL<iR);
pTmpVert[iL] = pTmpVert[iR];
pTmpVert[iR] = sTmp;
++iL; --iR;
}
}
assert(iL==(iR+1) || (iL==iR));
if (iL==iR)
{
const tbool bReadyRightSwap = pTmpVert[iR].vert[channel]<fSep;
if (bReadyRightSwap) ++iL;
else --iR;
}
// only need to weld when there is more than 1 instance of the (x,y,z)
if (iL_in < iR)
MergeVertsFast(piTriList_in_and_out, pTmpVert, pContext, iL_in, iR); // weld all left of fSep
if (iL < iR_in)
MergeVertsFast(piTriList_in_and_out, pTmpVert, pContext, iL, iR_in); // weld all right of (or equal to) fSep
}
}
static void MergeVertsSlow(int piTriList_in_and_out[], const SMikkTSpaceContext * pContext, const int pTable[], const int iEntries)
{
// this can be optimized further using a tree structure or more hashing.
int e=0;
for (e=0; e<iEntries; e++)
{
int i = pTable[e];
const int index = piTriList_in_and_out[i];
const SVec3 vP = GetPosition(pContext, index);
const SVec3 vN = GetNormal(pContext, index);
const SVec3 vT = GetTexCoord(pContext, index);
tbool bNotFound = TTRUE;
int e2=0, i2rec=-1;
while (e2<e && bNotFound)
{
const int i2 = pTable[e2];
const int index2 = piTriList_in_and_out[i2];
const SVec3 vP2 = GetPosition(pContext, index2);
const SVec3 vN2 = GetNormal(pContext, index2);
const SVec3 vT2 = GetTexCoord(pContext, index2);
i2rec = i2;
if (veq(vP,vP2) && veq(vN,vN2) && veq(vT,vT2))
bNotFound = TFALSE;
else
++e2;
}
// merge if previously found
if (!bNotFound)
piTriList_in_and_out[i] = piTriList_in_and_out[i2rec];
}
}
static void GenerateSharedVerticesIndexListSlow(int piTriList_in_and_out[], const SMikkTSpaceContext * pContext, const int iNrTrianglesIn)
{
int iNumUniqueVerts = 0, t=0, i=0;
for (t=0; t<iNrTrianglesIn; t++)
{
for (i=0; i<3; i++)
{
const int offs = t*3 + i;
const int index = piTriList_in_and_out[offs];
const SVec3 vP = GetPosition(pContext, index);
const SVec3 vN = GetNormal(pContext, index);
const SVec3 vT = GetTexCoord(pContext, index);
tbool bFound = TFALSE;
int t2=0, index2rec=-1;
while (!bFound && t2<=t)
{
int j=0;
while (!bFound && j<3)
{
const int index2 = piTriList_in_and_out[t2*3 + j];
const SVec3 vP2 = GetPosition(pContext, index2);
const SVec3 vN2 = GetNormal(pContext, index2);
const SVec3 vT2 = GetTexCoord(pContext, index2);
if (veq(vP,vP2) && veq(vN,vN2) && veq(vT,vT2))
bFound = TTRUE;
else
++j;
}
if (!bFound) ++t2;
}
assert(bFound);
// if we found our own
if (index2rec == index) { ++iNumUniqueVerts; }
piTriList_in_and_out[offs] = index2rec;
}
}
}
static int GenerateInitialVerticesIndexList(STriInfo pTriInfos[], int piTriList_out[], const SMikkTSpaceContext * pContext, const int iNrTrianglesIn)
{
int iTSpacesOffs = 0, f=0, t=0;
int iDstTriIndex = 0;
for (f=0; f<pContext->m_pInterface->m_getNumFaces(pContext); f++)
{
const int verts = pContext->m_pInterface->m_getNumVerticesOfFace(pContext, f);
if (verts!=3 && verts!=4) continue;
pTriInfos[iDstTriIndex].iOrgFaceNumber = f;
pTriInfos[iDstTriIndex].iTSpacesOffs = iTSpacesOffs;
if (verts==3)
{
unsigned char * pVerts = pTriInfos[iDstTriIndex].vert_num;
pVerts[0]=0; pVerts[1]=1; pVerts[2]=2;
piTriList_out[iDstTriIndex*3+0] = MakeIndex(f, 0);
piTriList_out[iDstTriIndex*3+1] = MakeIndex(f, 1);
piTriList_out[iDstTriIndex*3+2] = MakeIndex(f, 2);
++iDstTriIndex; // next
}
else
{
{
pTriInfos[iDstTriIndex+1].iOrgFaceNumber = f;
pTriInfos[iDstTriIndex+1].iTSpacesOffs = iTSpacesOffs;
}
{
// need an order independent way to evaluate
// tspace on quads. This is done by splitting
// along the shortest diagonal.
const int i0 = MakeIndex(f, 0);
const int i1 = MakeIndex(f, 1);
const int i2 = MakeIndex(f, 2);
const int i3 = MakeIndex(f, 3);
const SVec3 T0 = GetTexCoord(pContext, i0);
const SVec3 T1 = GetTexCoord(pContext, i1);
const SVec3 T2 = GetTexCoord(pContext, i2);
const SVec3 T3 = GetTexCoord(pContext, i3);
const float distSQ_02 = LengthSquared(vsub(T2,T0));
const float distSQ_13 = LengthSquared(vsub(T3,T1));
tbool bQuadDiagIs_02;
if (distSQ_02<distSQ_13)
bQuadDiagIs_02 = TTRUE;
else if (distSQ_13<distSQ_02)
bQuadDiagIs_02 = TFALSE;
else
{
const SVec3 P0 = GetPosition(pContext, i0);
const SVec3 P1 = GetPosition(pContext, i1);
const SVec3 P2 = GetPosition(pContext, i2);
const SVec3 P3 = GetPosition(pContext, i3);
const float distSQ_02 = LengthSquared(vsub(P2,P0));
const float distSQ_13 = LengthSquared(vsub(P3,P1));
bQuadDiagIs_02 = distSQ_13<distSQ_02 ? TFALSE : TTRUE;
}
if (bQuadDiagIs_02)
{
{
unsigned char * pVerts_A = pTriInfos[iDstTriIndex].vert_num;
pVerts_A[0]=0; pVerts_A[1]=1; pVerts_A[2]=2;
}
piTriList_out[iDstTriIndex*3+0] = i0;
piTriList_out[iDstTriIndex*3+1] = i1;
piTriList_out[iDstTriIndex*3+2] = i2;
++iDstTriIndex; // next
{
unsigned char * pVerts_B = pTriInfos[iDstTriIndex].vert_num;
pVerts_B[0]=0; pVerts_B[1]=2; pVerts_B[2]=3;
}
piTriList_out[iDstTriIndex*3+0] = i0;
piTriList_out[iDstTriIndex*3+1] = i2;
piTriList_out[iDstTriIndex*3+2] = i3;
++iDstTriIndex; // next
}
else
{
{
unsigned char * pVerts_A = pTriInfos[iDstTriIndex].vert_num;
pVerts_A[0]=0; pVerts_A[1]=1; pVerts_A[2]=3;
}
piTriList_out[iDstTriIndex*3+0] = i0;
piTriList_out[iDstTriIndex*3+1] = i1;
piTriList_out[iDstTriIndex*3+2] = i3;
++iDstTriIndex; // next
{
unsigned char * pVerts_B = pTriInfos[iDstTriIndex].vert_num;
pVerts_B[0]=1; pVerts_B[1]=2; pVerts_B[2]=3;
}
piTriList_out[iDstTriIndex*3+0] = i1;
piTriList_out[iDstTriIndex*3+1] = i2;
piTriList_out[iDstTriIndex*3+2] = i3;
++iDstTriIndex; // next
}
}
}
iTSpacesOffs += verts;
assert(iDstTriIndex<=iNrTrianglesIn);
}
for (t=0; t<iNrTrianglesIn; t++)
pTriInfos[t].iFlag = 0;
// return total amount of tspaces
return iTSpacesOffs;
}
static SVec3 GetPosition(const SMikkTSpaceContext * pContext, const int index)
{
int iF, iI;
SVec3 res; float pos[3];
IndexToData(&iF, &iI, index);
pContext->m_pInterface->m_getPosition(pContext, pos, iF, iI);
res.x=pos[0]; res.y=pos[1]; res.z=pos[2];
return res;
}
static SVec3 GetNormal(const SMikkTSpaceContext * pContext, const int index)
{
int iF, iI;
SVec3 res; float norm[3];
IndexToData(&iF, &iI, index);
pContext->m_pInterface->m_getNormal(pContext, norm, iF, iI);
res.x=norm[0]; res.y=norm[1]; res.z=norm[2];
return res;
}
static SVec3 GetTexCoord(const SMikkTSpaceContext * pContext, const int index)
{
int iF, iI;
SVec3 res; float texc[2];
IndexToData(&iF, &iI, index);
pContext->m_pInterface->m_getTexCoord(pContext, texc, iF, iI);
res.x=texc[0]; res.y=texc[1]; res.z=1.0f;
return res;
}
/////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////////////////////
typedef union {
struct
{
int i0, i1, f;
};
int array[3];
} SEdge;
static void BuildNeighborsFast(STriInfo pTriInfos[], SEdge * pEdges, const int piTriListIn[], const int iNrTrianglesIn);
static void BuildNeighborsSlow(STriInfo pTriInfos[], const int piTriListIn[], const int iNrTrianglesIn);
// returns the texture area times 2
static float CalcTexArea(const SMikkTSpaceContext * pContext, const int indices[])
{
const SVec3 t1 = GetTexCoord(pContext, indices[0]);
const SVec3 t2 = GetTexCoord(pContext, indices[1]);
const SVec3 t3 = GetTexCoord(pContext, indices[2]);
const float t21x = t2.x-t1.x;
const float t21y = t2.y-t1.y;
const float t31x = t3.x-t1.x;
const float t31y = t3.y-t1.y;
const float fSignedAreaSTx2 = t21x*t31y - t21y*t31x;
return fSignedAreaSTx2<0 ? (-fSignedAreaSTx2) : fSignedAreaSTx2;
}
static void InitTriInfo(STriInfo pTriInfos[], const int piTriListIn[], const SMikkTSpaceContext * pContext, const int iNrTrianglesIn)
{
int f=0, i=0, t=0;
// pTriInfos[f].iFlag is cleared in GenerateInitialVerticesIndexList() which is called before this function.
// generate neighbor info list
for (f=0; f<iNrTrianglesIn; f++)
for (i=0; i<3; i++)
{
pTriInfos[f].FaceNeighbors[i] = -1;
pTriInfos[f].AssignedGroup[i] = NULL;
pTriInfos[f].vOs.x=0.0f; pTriInfos[f].vOs.y=0.0f; pTriInfos[f].vOs.z=0.0f;
pTriInfos[f].vOt.x=0.0f; pTriInfos[f].vOt.y=0.0f; pTriInfos[f].vOt.z=0.0f;
pTriInfos[f].fMagS = 0;
pTriInfos[f].fMagT = 0;
// assumed bad
pTriInfos[f].iFlag |= GROUP_WITH_ANY;
}
// evaluate first order derivatives
for (f=0; f<iNrTrianglesIn; f++)
{
// initial values
const SVec3 v1 = GetPosition(pContext, piTriListIn[f*3+0]);
const SVec3 v2 = GetPosition(pContext, piTriListIn[f*3+1]);
const SVec3 v3 = GetPosition(pContext, piTriListIn[f*3+2]);
const SVec3 t1 = GetTexCoord(pContext, piTriListIn[f*3+0]);
const SVec3 t2 = GetTexCoord(pContext, piTriListIn[f*3+1]);
const SVec3 t3 = GetTexCoord(pContext, piTriListIn[f*3+2]);
const float t21x = t2.x-t1.x;
const float t21y = t2.y-t1.y;
const float t31x = t3.x-t1.x;
const float t31y = t3.y-t1.y;
const SVec3 d1 = vsub(v2,v1);
const SVec3 d2 = vsub(v3,v1);
const float fSignedAreaSTx2 = t21x*t31y - t21y*t31x;
//assert(fSignedAreaSTx2!=0);
SVec3 vOs = vsub(vscale(t31y,d1), vscale(t21y,d2)); // eq 18
SVec3 vOt = vadd(vscale(-t31x,d1), vscale(t21x,d2)); // eq 19
pTriInfos[f].iFlag |= (fSignedAreaSTx2>0 ? ORIENT_PRESERVING : 0);
if ( NotZero(fSignedAreaSTx2) )
{
const float fAbsArea = fabsf(fSignedAreaSTx2);
const float fLenOs = Length(vOs);
const float fLenOt = Length(vOt);
const float fS = (pTriInfos[f].iFlag&ORIENT_PRESERVING)==0 ? (-1.0f) : 1.0f;
if ( NotZero(fLenOs) ) pTriInfos[f].vOs = vscale(fS/fLenOs, vOs);
if ( NotZero(fLenOt) ) pTriInfos[f].vOt = vscale(fS/fLenOt, vOt);
// evaluate magnitudes prior to normalization of vOs and vOt
pTriInfos[f].fMagS = fLenOs / fAbsArea;
pTriInfos[f].fMagT = fLenOt / fAbsArea;
// if this is a good triangle
if ( NotZero(pTriInfos[f].fMagS) && NotZero(pTriInfos[f].fMagT))
pTriInfos[f].iFlag &= (~GROUP_WITH_ANY);
}
}
// force otherwise healthy quads to a fixed orientation
while (t<(iNrTrianglesIn-1))
{
const int iFO_a = pTriInfos[t].iOrgFaceNumber;
const int iFO_b = pTriInfos[t+1].iOrgFaceNumber;
if (iFO_a==iFO_b) // this is a quad
{
const tbool bIsDeg_a = (pTriInfos[t].iFlag&MARK_DEGENERATE)!=0 ? TTRUE : TFALSE;
const tbool bIsDeg_b = (pTriInfos[t+1].iFlag&MARK_DEGENERATE)!=0 ? TTRUE : TFALSE;
// bad triangles should already have been removed by
// DegenPrologue(), but just in case check bIsDeg_a and bIsDeg_a are false
if ((bIsDeg_a||bIsDeg_b)==TFALSE)
{
const tbool bOrientA = (pTriInfos[t].iFlag&ORIENT_PRESERVING)!=0 ? TTRUE : TFALSE;
const tbool bOrientB = (pTriInfos[t+1].iFlag&ORIENT_PRESERVING)!=0 ? TTRUE : TFALSE;
// if this happens the quad has extremely bad mapping!!
if (bOrientA!=bOrientB)
{
//printf("found quad with bad mapping\n");
tbool bChooseOrientFirstTri = TFALSE;
if ((pTriInfos[t+1].iFlag&GROUP_WITH_ANY)!=0) bChooseOrientFirstTri = TTRUE;
else if ( CalcTexArea(pContext, &piTriListIn[t*3+0]) >= CalcTexArea(pContext, &piTriListIn[(t+1)*3+0]) )
bChooseOrientFirstTri = TTRUE;
// force match
{
const int t0 = bChooseOrientFirstTri ? t : (t+1);
const int t1 = bChooseOrientFirstTri ? (t+1) : t;
pTriInfos[t1].iFlag &= (~ORIENT_PRESERVING); // clear first
pTriInfos[t1].iFlag |= (pTriInfos[t0].iFlag&ORIENT_PRESERVING); // copy bit
}
}
}
t += 2;
}
else
++t;
}
// match up edge pairs
{
SEdge * pEdges = (SEdge *) malloc(sizeof(SEdge)*iNrTrianglesIn*3);
if (pEdges==NULL)
BuildNeighborsSlow(pTriInfos, piTriListIn, iNrTrianglesIn);
else
{
BuildNeighborsFast(pTriInfos, pEdges, piTriListIn, iNrTrianglesIn);
free(pEdges);
}
}
}
/////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////////////////////
static tbool AssignRecur(const int piTriListIn[], STriInfo psTriInfos[], const int iMyTriIndex, SGroup * pGroup);
static void AddTriToGroup(SGroup * pGroup, const int iTriIndex);
static int Build4RuleGroups(STriInfo pTriInfos[], SGroup pGroups[], int piGroupTrianglesBuffer[], const int piTriListIn[], const int iNrTrianglesIn)
{
const int iNrMaxGroups = iNrTrianglesIn*3;
int iNrActiveGroups = 0;
int iOffset = 0, f=0, i=0;
(void)iNrMaxGroups; /* quiet warnings in non debug mode */
for (f=0; f<iNrTrianglesIn; f++)
{
for (i=0; i<3; i++)
{
// if not assigned to a group
if ((pTriInfos[f].iFlag&GROUP_WITH_ANY)==0 && pTriInfos[f].AssignedGroup[i]==NULL)
{
tbool bOrPre;
int neigh_indexL, neigh_indexR;
const int vert_index = piTriListIn[f*3+i];
assert(iNrActiveGroups<iNrMaxGroups);
pTriInfos[f].AssignedGroup[i] = &pGroups[iNrActiveGroups];
pTriInfos[f].AssignedGroup[i]->iVertexRepresentitive = vert_index;
pTriInfos[f].AssignedGroup[i]->bOrientPreservering = (pTriInfos[f].iFlag&ORIENT_PRESERVING)!=0;
pTriInfos[f].AssignedGroup[i]->iNrFaces = 0;
pTriInfos[f].AssignedGroup[i]->pFaceIndices = &piGroupTrianglesBuffer[iOffset];
++iNrActiveGroups;
AddTriToGroup(pTriInfos[f].AssignedGroup[i], f);
bOrPre = (pTriInfos[f].iFlag&ORIENT_PRESERVING)!=0 ? TTRUE : TFALSE;
neigh_indexL = pTriInfos[f].FaceNeighbors[i];
neigh_indexR = pTriInfos[f].FaceNeighbors[i>0?(i-1):2];
if (neigh_indexL>=0) // neighbor
{
const tbool bAnswer =
AssignRecur(piTriListIn, pTriInfos, neigh_indexL,
pTriInfos[f].AssignedGroup[i] );
const tbool bOrPre2 = (pTriInfos[neigh_indexL].iFlag&ORIENT_PRESERVING)!=0 ? TTRUE : TFALSE;
const tbool bDiff = bOrPre!=bOrPre2 ? TTRUE : TFALSE;
assert(bAnswer || bDiff);
(void)bAnswer, (void)bDiff; /* quiet warnings in non debug mode */
}
if (neigh_indexR>=0) // neighbor
{
const tbool bAnswer =
AssignRecur(piTriListIn, pTriInfos, neigh_indexR,
pTriInfos[f].AssignedGroup[i] );
const tbool bOrPre2 = (pTriInfos[neigh_indexR].iFlag&ORIENT_PRESERVING)!=0 ? TTRUE : TFALSE;
const tbool bDiff = bOrPre!=bOrPre2 ? TTRUE : TFALSE;
assert(bAnswer || bDiff);
(void)bAnswer, (void)bDiff; /* quiet warnings in non debug mode */
}
// update offset
iOffset += pTriInfos[f].AssignedGroup[i]->iNrFaces;
// since the groups are disjoint a triangle can never
// belong to more than 3 groups. Subsequently something
// is completely screwed if this assertion ever hits.
assert(iOffset <= iNrMaxGroups);
}
}
}
return iNrActiveGroups;
}
static void AddTriToGroup(SGroup * pGroup, const int iTriIndex)
{
pGroup->pFaceIndices[pGroup->iNrFaces] = iTriIndex;
++pGroup->iNrFaces;
}
static tbool AssignRecur(const int piTriListIn[], STriInfo psTriInfos[],
const int iMyTriIndex, SGroup * pGroup)
{
STriInfo * pMyTriInfo = &psTriInfos[iMyTriIndex];
// track down vertex
const int iVertRep = pGroup->iVertexRepresentitive;
const int * pVerts = &piTriListIn[3*iMyTriIndex+0];
int i=-1;
if (pVerts[0]==iVertRep) i=0;
else if (pVerts[1]==iVertRep) i=1;
else if (pVerts[2]==iVertRep) i=2;
assert(i>=0 && i<3);
// early out
if (pMyTriInfo->AssignedGroup[i] == pGroup) return TTRUE;
else if (pMyTriInfo->AssignedGroup[i]!=NULL) return TFALSE;
if ((pMyTriInfo->iFlag&GROUP_WITH_ANY)!=0)
{
// first to group with a group-with-anything triangle
// determines it's orientation.
// This is the only existing order dependency in the code!!
if ( pMyTriInfo->AssignedGroup[0] == NULL &&
pMyTriInfo->AssignedGroup[1] == NULL &&
pMyTriInfo->AssignedGroup[2] == NULL )
{
pMyTriInfo->iFlag &= (~ORIENT_PRESERVING);
pMyTriInfo->iFlag |= (pGroup->bOrientPreservering ? ORIENT_PRESERVING : 0);
}
}
{
const tbool bOrient = (pMyTriInfo->iFlag&ORIENT_PRESERVING)!=0 ? TTRUE : TFALSE;
if (bOrient != pGroup->bOrientPreservering) return TFALSE;
}
AddTriToGroup(pGroup, iMyTriIndex);
pMyTriInfo->AssignedGroup[i] = pGroup;
{
const int neigh_indexL = pMyTriInfo->FaceNeighbors[i];
const int neigh_indexR = pMyTriInfo->FaceNeighbors[i>0?(i-1):2];
if (neigh_indexL>=0)
AssignRecur(piTriListIn, psTriInfos, neigh_indexL, pGroup);
if (neigh_indexR>=0)
AssignRecur(piTriListIn, psTriInfos, neigh_indexR, pGroup);
}
return TTRUE;
}
/////////////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////////////////////
static tbool CompareSubGroups(const SSubGroup * pg1, const SSubGroup * pg2);
static void QuickSort(int* pSortBuffer, int iLeft, int iRight, unsigned int uSeed);
static STSpace EvalTspace(int face_indices[], const int iFaces, const int piTriListIn[], const STriInfo pTriInfos[], const SMikkTSpaceContext * pContext, const int iVertexRepresentitive);
static tbool GenerateTSpaces(STSpace psTspace[], const STriInfo pTriInfos[], const SGroup pGroups[],
const int iNrActiveGroups, const int piTriListIn[], const float fThresCos,
const SMikkTSpaceContext * pContext)
{
STSpace * pSubGroupTspace = NULL;
SSubGroup * pUniSubGroups = NULL;
int * pTmpMembers = NULL;
int iMaxNrFaces=0, iUniqueTspaces=0, g=0, i=0;
for (g=0; g<iNrActiveGroups; g++)
if (iMaxNrFaces < pGroups[g].iNrFaces)
iMaxNrFaces = pGroups[g].iNrFaces;
if (iMaxNrFaces == 0) return TTRUE;
// make initial allocations
pSubGroupTspace = (STSpace *) malloc(sizeof(STSpace)*iMaxNrFaces);
pUniSubGroups = (SSubGroup *) malloc(sizeof(SSubGroup)*iMaxNrFaces);
pTmpMembers = (int *) malloc(sizeof(int)*iMaxNrFaces);
if (pSubGroupTspace==NULL || pUniSubGroups==NULL || pTmpMembers==NULL)
{
if (pSubGroupTspace!=NULL) free(pSubGroupTspace);
if (pUniSubGroups!=NULL) free(pUniSubGroups);
if (pTmpMembers!=NULL) free(pTmpMembers);
return TFALSE;
}
iUniqueTspaces = 0;
for (g=0; g<iNrActiveGroups; g++)
{
const SGroup * pGroup = &pGroups[g];
int iUniqueSubGroups = 0, s=0;
for (i=0; i<pGroup->iNrFaces; i++) // triangles
{
const int f = pGroup->pFaceIndices[i]; // triangle number
int index=-1, iVertIndex=-1, iOF_1=-1, iMembers=0, j=0, l=0;
SSubGroup tmp_group;
tbool bFound;
SVec3 n, vOs, vOt;
if (pTriInfos[f].AssignedGroup[0]==pGroup) index=0;
else if (pTriInfos[f].AssignedGroup[1]==pGroup) index=1;
else if (pTriInfos[f].AssignedGroup[2]==pGroup) index=2;
assert(index>=0 && index<3);
iVertIndex = piTriListIn[f*3+index];
assert(iVertIndex==pGroup->iVertexRepresentitive);
// is normalized already
n = GetNormal(pContext, iVertIndex);
// project
vOs = vsub(pTriInfos[f].vOs, vscale(vdot(n,pTriInfos[f].vOs), n));
vOt = vsub(pTriInfos[f].vOt, vscale(vdot(n,pTriInfos[f].vOt), n));
if ( VNotZero(vOs) ) vOs = Normalize(vOs);
if ( VNotZero(vOt) ) vOt = Normalize(vOt);
// original face number
iOF_1 = pTriInfos[f].iOrgFaceNumber;
iMembers = 0;
for (j=0; j<pGroup->iNrFaces; j++)
{
const int t = pGroup->pFaceIndices[j]; // triangle number
const int iOF_2 = pTriInfos[t].iOrgFaceNumber;
// project
SVec3 vOs2 = vsub(pTriInfos[t].vOs, vscale(vdot(n,pTriInfos[t].vOs), n));
SVec3 vOt2 = vsub(pTriInfos[t].vOt, vscale(vdot(n,pTriInfos[t].vOt), n));
if ( VNotZero(vOs2) ) vOs2 = Normalize(vOs2);
if ( VNotZero(vOt2) ) vOt2 = Normalize(vOt2);
{
const tbool bAny = ( (pTriInfos[f].iFlag | pTriInfos[t].iFlag) & GROUP_WITH_ANY )!=0 ? TTRUE : TFALSE;
// make sure triangles which belong to the same quad are joined.
const tbool bSameOrgFace = iOF_1==iOF_2 ? TTRUE : TFALSE;
const float fCosS = vdot(vOs,vOs2);
const float fCosT = vdot(vOt,vOt2);
assert(f!=t || bSameOrgFace); // sanity check
if (bAny || bSameOrgFace || (fCosS>fThresCos && fCosT>fThresCos))
pTmpMembers[iMembers++] = t;
}
}
// sort pTmpMembers
tmp_group.iNrFaces = iMembers;
tmp_group.pTriMembers = pTmpMembers;
if (iMembers>1)
{
unsigned int uSeed = INTERNAL_RND_SORT_SEED; // could replace with a random seed?
QuickSort(pTmpMembers, 0, iMembers-1, uSeed);
}
// look for an existing match
bFound = TFALSE;
l=0;
while (l<iUniqueSubGroups && !bFound)
{
bFound = CompareSubGroups(&tmp_group, &pUniSubGroups[l]);
if (!bFound) ++l;
}
// assign tangent space index
assert(bFound || l==iUniqueSubGroups);
//piTempTangIndices[f*3+index] = iUniqueTspaces+l;
// if no match was found we allocate a new subgroup
if (!bFound)
{
// insert new subgroup
int * pIndices = (int *) malloc(sizeof(int)*iMembers);
if (pIndices==NULL)
{
// clean up and return false
int s=0;
for (s=0; s<iUniqueSubGroups; s++)
free(pUniSubGroups[s].pTriMembers);
free(pUniSubGroups);
free(pTmpMembers);
free(pSubGroupTspace);
return TFALSE;
}
pUniSubGroups[iUniqueSubGroups].iNrFaces = iMembers;
pUniSubGroups[iUniqueSubGroups].pTriMembers = pIndices;
memcpy(pIndices, tmp_group.pTriMembers, iMembers*sizeof(int));
pSubGroupTspace[iUniqueSubGroups] =
EvalTspace(tmp_group.pTriMembers, iMembers, piTriListIn, pTriInfos, pContext, pGroup->iVertexRepresentitive);
++iUniqueSubGroups;
}
// output tspace
{
const int iOffs = pTriInfos[f].iTSpacesOffs;
const int iVert = pTriInfos[f].vert_num[index];
STSpace * pTS_out = &psTspace[iOffs+iVert];
assert(pTS_out->iCounter<2);
assert(((pTriInfos[f].iFlag&ORIENT_PRESERVING)!=0) == pGroup->bOrientPreservering);
if (pTS_out->iCounter==1)
{
*pTS_out = AvgTSpace(pTS_out, &pSubGroupTspace[l]);
pTS_out->iCounter = 2; // update counter
pTS_out->bOrient = pGroup->bOrientPreservering;
}
else
{
assert(pTS_out->iCounter==0);
*pTS_out = pSubGroupTspace[l];
pTS_out->iCounter = 1; // update counter
pTS_out->bOrient = pGroup->bOrientPreservering;
}
}
}
// clean up and offset iUniqueTspaces
for (s=0; s<iUniqueSubGroups; s++)
free(pUniSubGroups[s].pTriMembers);
iUniqueTspaces += iUniqueSubGroups;
}
// clean up
free(pUniSubGroups);
free(pTmpMembers);
free(pSubGroupTspace);
return TTRUE;
}
static STSpace EvalTspace(int face_indices[], const int iFaces, const int piTriListIn[], const STriInfo pTriInfos[],
const SMikkTSpaceContext * pContext, const int iVertexRepresentitive)
{
STSpace res;
float fAngleSum = 0;
int face=0;
res.vOs.x=0.0f; res.vOs.y=0.0f; res.vOs.z=0.0f;
res.vOt.x=0.0f; res.vOt.y=0.0f; res.vOt.z=0.0f;
res.fMagS = 0; res.fMagT = 0;
for (face=0; face<iFaces; face++)
{
const int f = face_indices[face];
// only valid triangles get to add their contribution
if ( (pTriInfos[f].iFlag&GROUP_WITH_ANY)==0 )
{
SVec3 n, vOs, vOt, p0, p1, p2, v1, v2;
float fCos, fAngle, fMagS, fMagT;
int i=-1, index=-1, i0=-1, i1=-1, i2=-1;
if (piTriListIn[3*f+0]==iVertexRepresentitive) i=0;
else if (piTriListIn[3*f+1]==iVertexRepresentitive) i=1;
else if (piTriListIn[3*f+2]==iVertexRepresentitive) i=2;
assert(i>=0 && i<3);
// project
index = piTriListIn[3*f+i];
n = GetNormal(pContext, index);
vOs = vsub(pTriInfos[f].vOs, vscale(vdot(n,pTriInfos[f].vOs), n));
vOt = vsub(pTriInfos[f].vOt, vscale(vdot(n,pTriInfos[f].vOt), n));
if ( VNotZero(vOs) ) vOs = Normalize(vOs);
if ( VNotZero(vOt) ) vOt = Normalize(vOt);
i2 = piTriListIn[3*f + (i<2?(i+1):0)];
i1 = piTriListIn[3*f + i];
i0 = piTriListIn[3*f + (i>0?(i-1):2)];
p0 = GetPosition(pContext, i0);
p1 = GetPosition(pContext, i1);
p2 = GetPosition(pContext, i2);
v1 = vsub(p0,p1);
v2 = vsub(p2,p1);
// project
v1 = vsub(v1, vscale(vdot(n,v1),n)); if ( VNotZero(v1) ) v1 = Normalize(v1);
v2 = vsub(v2, vscale(vdot(n,v2),n)); if ( VNotZero(v2) ) v2 = Normalize(v2);
// weight contribution by the angle
// between the two edge vectors
fCos = vdot(v1,v2); fCos=fCos>1?1:(fCos<(-1) ? (-1) : fCos);
fAngle = (float) acos(fCos);
fMagS = pTriInfos[f].fMagS;
fMagT = pTriInfos[f].fMagT;
res.vOs=vadd(res.vOs, vscale(fAngle,vOs));
res.vOt=vadd(res.vOt,vscale(fAngle,vOt));
res.fMagS+=(fAngle*fMagS);
res.fMagT+=(fAngle*fMagT);
fAngleSum += fAngle;
}
}
// normalize
if ( VNotZero(res.vOs) ) res.vOs = Normalize(res.vOs);
if ( VNotZero(res.vOt) ) res.vOt = Normalize(res.vOt);
if (fAngleSum>0)
{
res.fMagS /= fAngleSum;
res.fMagT /= fAngleSum;
}
return res;
}
static tbool CompareSubGroups(const SSubGroup * pg1, const SSubGroup * pg2)
{
tbool bStillSame=TTRUE;
int i=0;
if (pg1->iNrFaces!=pg2->iNrFaces) return TFALSE;
while (i<pg1->iNrFaces && bStillSame)
{
bStillSame = pg1->pTriMembers[i]==pg2->pTriMembers[i] ? TTRUE : TFALSE;
if (bStillSame) ++i;
}
return bStillSame;
}
static void QuickSort(int* pSortBuffer, int iLeft, int iRight, unsigned int uSeed)
{
int iL, iR, n, index, iMid, iTmp;
// Random
unsigned int t=uSeed&31;
t=(uSeed<<t)|(uSeed>>(32-t));
uSeed=uSeed+t+3;
// Random end
iL=iLeft; iR=iRight;
n = (iR-iL)+1;
assert(n>=0);
index = (int) (uSeed%n);
iMid=pSortBuffer[index + iL];
do
{
while (pSortBuffer[iL] < iMid)
++iL;
while (pSortBuffer[iR] > iMid)
--iR;
if (iL <= iR)
{
iTmp = pSortBuffer[iL];
pSortBuffer[iL] = pSortBuffer[iR];
pSortBuffer[iR] = iTmp;
++iL; --iR;
}
}
while (iL <= iR);
if (iLeft < iR)
QuickSort(pSortBuffer, iLeft, iR, uSeed);
if (iL < iRight)
QuickSort(pSortBuffer, iL, iRight, uSeed);
}
/////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////////////////////////////////////////////////////////////////
static void QuickSortEdges(SEdge * pSortBuffer, int iLeft, int iRight, const int channel, unsigned int uSeed);
static void GetEdge(int * i0_out, int * i1_out, int * edgenum_out, const int indices[], const int i0_in, const int i1_in);
static void BuildNeighborsFast(STriInfo pTriInfos[], SEdge * pEdges, const int piTriListIn[], const int iNrTrianglesIn)
{
// build array of edges
unsigned int uSeed = INTERNAL_RND_SORT_SEED; // could replace with a random seed?
int iEntries=0, iCurStartIndex=-1, f=0, i=0;
for (f=0; f<iNrTrianglesIn; f++)
for (i=0; i<3; i++)
{
const int i0 = piTriListIn[f*3+i];
const int i1 = piTriListIn[f*3+(i<2?(i+1):0)];
pEdges[f*3+i].i0 = i0 < i1 ? i0 : i1; // put minimum index in i0
pEdges[f*3+i].i1 = !(i0 < i1) ? i0 : i1; // put maximum index in i1
pEdges[f*3+i].f = f; // record face number
}
// sort over all edges by i0, this is the pricy one.
QuickSortEdges(pEdges, 0, iNrTrianglesIn*3-1, 0, uSeed); // sort channel 0 which is i0
// sub sort over i1, should be fast.
// could replace this with a 64 bit int sort over (i0,i1)
// with i0 as msb in the quicksort call above.
iEntries = iNrTrianglesIn*3;
iCurStartIndex = 0;
for (i=1; i<iEntries; i++)
{
if (pEdges[iCurStartIndex].i0 != pEdges[i].i0)
{
const int iL = iCurStartIndex;
const int iR = i-1;
//const int iElems = i-iL;
iCurStartIndex = i;
QuickSortEdges(pEdges, iL, iR, 1, uSeed); // sort channel 1 which is i1
}
}
// sub sort over f, which should be fast.
// this step is to remain compliant with BuildNeighborsSlow() when
// more than 2 triangles use the same edge (such as a butterfly topology).
iCurStartIndex = 0;
for (i=1; i<iEntries; i++)
{
if (pEdges[iCurStartIndex].i0 != pEdges[i].i0 || pEdges[iCurStartIndex].i1 != pEdges[i].i1)
{
const int iL = iCurStartIndex;
const int iR = i-1;
//const int iElems = i-iL;
iCurStartIndex = i;
QuickSortEdges(pEdges, iL, iR, 2, uSeed); // sort channel 2 which is f
}
}
// pair up, adjacent triangles
for (i=0; i<iEntries; i++)
{
const int i0=pEdges[i].i0;
const int i1=pEdges[i].i1;
const int f = pEdges[i].f;
tbool bUnassigned_A;
int i0_A, i1_A;
int edgenum_A, edgenum_B=0; // 0,1 or 2
GetEdge(&i0_A, &i1_A, &edgenum_A, &piTriListIn[f*3], i0, i1); // resolve index ordering and edge_num
bUnassigned_A = pTriInfos[f].FaceNeighbors[edgenum_A] == -1 ? TTRUE : TFALSE;
if (bUnassigned_A)
{
// get true index ordering
int j=i+1, t;
tbool bNotFound = TTRUE;
while (j<iEntries && i0==pEdges[j].i0 && i1==pEdges[j].i1 && bNotFound)
{
tbool bUnassigned_B;
int i0_B, i1_B;
t = pEdges[j].f;
// flip i0_B and i1_B
GetEdge(&i1_B, &i0_B, &edgenum_B, &piTriListIn[t*3], pEdges[j].i0, pEdges[j].i1); // resolve index ordering and edge_num
//assert(!(i0_A==i1_B && i1_A==i0_B));
bUnassigned_B = pTriInfos[t].FaceNeighbors[edgenum_B]==-1 ? TTRUE : TFALSE;
if (i0_A==i0_B && i1_A==i1_B && bUnassigned_B)
bNotFound = TFALSE;
else
++j;
}
if (!bNotFound)
{
int t = pEdges[j].f;
pTriInfos[f].FaceNeighbors[edgenum_A] = t;
//assert(pTriInfos[t].FaceNeighbors[edgenum_B]==-1);
pTriInfos[t].FaceNeighbors[edgenum_B] = f;
}
}
}
}
static void BuildNeighborsSlow(STriInfo pTriInfos[], const int piTriListIn[], const int iNrTrianglesIn)
{
int f=0, i=0;
for (f=0; f<iNrTrianglesIn; f++)
{
for (i=0; i<3; i++)
{
// if unassigned
if (pTriInfos[f].FaceNeighbors[i] == -1)
{
const int i0_A = piTriListIn[f*3+i];
const int i1_A = piTriListIn[f*3+(i<2?(i+1):0)];
// search for a neighbor
tbool bFound = TFALSE;
int t=0, j=0;
while (!bFound && t<iNrTrianglesIn)
{
if (t!=f)
{
j=0;
while (!bFound && j<3)
{
// in rev order
const int i1_B = piTriListIn[t*3+j];
const int i0_B = piTriListIn[t*3+(j<2?(j+1):0)];
//assert(!(i0_A==i1_B && i1_A==i0_B));
if (i0_A==i0_B && i1_A==i1_B)
bFound = TTRUE;
else
++j;
}
}
if (!bFound) ++t;
}
// assign neighbors
if (bFound)
{
pTriInfos[f].FaceNeighbors[i] = t;
//assert(pTriInfos[t].FaceNeighbors[j]==-1);
pTriInfos[t].FaceNeighbors[j] = f;
}
}
}
}
}
static void QuickSortEdges(SEdge * pSortBuffer, int iLeft, int iRight, const int channel, unsigned int uSeed)
{
unsigned int t;
int iL, iR, n, index, iMid;
// early out
SEdge sTmp;
const int iElems = iRight-iLeft+1;
if (iElems<2) return;
else if (iElems==2)
{
if (pSortBuffer[iLeft].array[channel] > pSortBuffer[iRight].array[channel])
{
sTmp = pSortBuffer[iLeft];
pSortBuffer[iLeft] = pSortBuffer[iRight];
pSortBuffer[iRight] = sTmp;
}
return;
}
// Random
t=uSeed&31;
t=(uSeed<<t)|(uSeed>>(32-t));
uSeed=uSeed+t+3;
// Random end
iL=iLeft, iR=iRight;
n = (iR-iL)+1;
assert(n>=0);
index = (int) (uSeed%n);
iMid=pSortBuffer[index + iL].array[channel];
do
{
while (pSortBuffer[iL].array[channel] < iMid)
++iL;
while (pSortBuffer[iR].array[channel] > iMid)
--iR;
if (iL <= iR)
{
sTmp = pSortBuffer[iL];
pSortBuffer[iL] = pSortBuffer[iR];
pSortBuffer[iR] = sTmp;
++iL; --iR;
}
}
while (iL <= iR);
if (iLeft < iR)
QuickSortEdges(pSortBuffer, iLeft, iR, channel, uSeed);
if (iL < iRight)
QuickSortEdges(pSortBuffer, iL, iRight, channel, uSeed);
}
// resolve ordering and edge number
static void GetEdge(int * i0_out, int * i1_out, int * edgenum_out, const int indices[], const int i0_in, const int i1_in)
{
*edgenum_out = -1;
// test if first index is on the edge
if (indices[0]==i0_in || indices[0]==i1_in)
{
// test if second index is on the edge
if (indices[1]==i0_in || indices[1]==i1_in)
{
edgenum_out[0]=0; // first edge
i0_out[0]=indices[0];
i1_out[0]=indices[1];
}
else
{
edgenum_out[0]=2; // third edge
i0_out[0]=indices[2];
i1_out[0]=indices[0];
}
}
else
{
// only second and third index is on the edge
edgenum_out[0]=1; // second edge
i0_out[0]=indices[1];
i1_out[0]=indices[2];
}
}
/////////////////////////////////////////////////////////////////////////////////////////////
/////////////////////////////////// Degenerate triangles ////////////////////////////////////
static void DegenPrologue(STriInfo pTriInfos[], int piTriList_out[], const int iNrTrianglesIn, const int iTotTris)
{
int iNextGoodTriangleSearchIndex=-1;
tbool bStillFindingGoodOnes;
// locate quads with only one good triangle
int t=0;
while (t<(iTotTris-1))
{
const int iFO_a = pTriInfos[t].iOrgFaceNumber;
const int iFO_b = pTriInfos[t+1].iOrgFaceNumber;
if (iFO_a==iFO_b) // this is a quad
{
const tbool bIsDeg_a = (pTriInfos[t].iFlag&MARK_DEGENERATE)!=0 ? TTRUE : TFALSE;
const tbool bIsDeg_b = (pTriInfos[t+1].iFlag&MARK_DEGENERATE)!=0 ? TTRUE : TFALSE;
if ((bIsDeg_a^bIsDeg_b)!=0)
{
pTriInfos[t].iFlag |= QUAD_ONE_DEGEN_TRI;
pTriInfos[t+1].iFlag |= QUAD_ONE_DEGEN_TRI;
}
t += 2;
}
else
++t;
}
// reorder list so all degen triangles are moved to the back
// without reordering the good triangles
iNextGoodTriangleSearchIndex = 1;
t=0;
bStillFindingGoodOnes = TTRUE;
while (t<iNrTrianglesIn && bStillFindingGoodOnes)
{
const tbool bIsGood = (pTriInfos[t].iFlag&MARK_DEGENERATE)==0 ? TTRUE : TFALSE;
if (bIsGood)
{
if (iNextGoodTriangleSearchIndex < (t+2))
iNextGoodTriangleSearchIndex = t+2;
}
else
{
int t0, t1;
// search for the first good triangle.
tbool bJustADegenerate = TTRUE;
while (bJustADegenerate && iNextGoodTriangleSearchIndex<iTotTris)
{
const tbool bIsGood = (pTriInfos[iNextGoodTriangleSearchIndex].iFlag&MARK_DEGENERATE)==0 ? TTRUE : TFALSE;
if (bIsGood) bJustADegenerate=TFALSE;
else ++iNextGoodTriangleSearchIndex;
}
t0 = t;
t1 = iNextGoodTriangleSearchIndex;
++iNextGoodTriangleSearchIndex;
assert(iNextGoodTriangleSearchIndex > (t+1));
// swap triangle t0 and t1
if (!bJustADegenerate)
{
int i=0;
for (i=0; i<3; i++)
{
const int index = piTriList_out[t0*3+i];
piTriList_out[t0*3+i] = piTriList_out[t1*3+i];
piTriList_out[t1*3+i] = index;
}
{
const STriInfo tri_info = pTriInfos[t0];
pTriInfos[t0] = pTriInfos[t1];
pTriInfos[t1] = tri_info;
}
}
else
bStillFindingGoodOnes = TFALSE; // this is not supposed to happen
}
if (bStillFindingGoodOnes) ++t;
}
assert(bStillFindingGoodOnes); // code will still work.
assert(iNrTrianglesIn == t);
}
static void DegenEpilogue(STSpace psTspace[], STriInfo pTriInfos[], int piTriListIn[], const SMikkTSpaceContext * pContext, const int iNrTrianglesIn, const int iTotTris)
{
int t=0, i=0;
// deal with degenerate triangles
// punishment for degenerate triangles is O(N^2)
for (t=iNrTrianglesIn; t<iTotTris; t++)
{
// degenerate triangles on a quad with one good triangle are skipped
// here but processed in the next loop
const tbool bSkip = (pTriInfos[t].iFlag&QUAD_ONE_DEGEN_TRI)!=0 ? TTRUE : TFALSE;
if (!bSkip)
{
for (i=0; i<3; i++)
{
const int index1 = piTriListIn[t*3+i];
// search through the good triangles
tbool bNotFound = TTRUE;
int j=0;
while (bNotFound && j<(3*iNrTrianglesIn))
{
const int index2 = piTriListIn[j];
if (index1==index2) bNotFound=TFALSE;
else ++j;
}
if (!bNotFound)
{
const int iTri = j/3;
const int iVert = j%3;
const int iSrcVert=pTriInfos[iTri].vert_num[iVert];
const int iSrcOffs=pTriInfos[iTri].iTSpacesOffs;
const int iDstVert=pTriInfos[t].vert_num[i];
const int iDstOffs=pTriInfos[t].iTSpacesOffs;
// copy tspace
psTspace[iDstOffs+iDstVert] = psTspace[iSrcOffs+iSrcVert];
}
}
}
}
// deal with degenerate quads with one good triangle
for (t=0; t<iNrTrianglesIn; t++)
{
// this triangle belongs to a quad where the
// other triangle is degenerate
if ( (pTriInfos[t].iFlag&QUAD_ONE_DEGEN_TRI)!=0 )
{
SVec3 vDstP;
int iOrgF=-1, i=0;
tbool bNotFound;
unsigned char * pV = pTriInfos[t].vert_num;
int iFlag = (1<<pV[0]) | (1<<pV[1]) | (1<<pV[2]);
int iMissingIndex = 0;
if ((iFlag&2)==0) iMissingIndex=1;
else if ((iFlag&4)==0) iMissingIndex=2;
else if ((iFlag&8)==0) iMissingIndex=3;
iOrgF = pTriInfos[t].iOrgFaceNumber;
vDstP = GetPosition(pContext, MakeIndex(iOrgF, iMissingIndex));
bNotFound = TTRUE;
i=0;
while (bNotFound && i<3)
{
const int iVert = pV[i];
const SVec3 vSrcP = GetPosition(pContext, MakeIndex(iOrgF, iVert));
if (veq(vSrcP, vDstP)==TTRUE)
{
const int iOffs = pTriInfos[t].iTSpacesOffs;
psTspace[iOffs+iMissingIndex] = psTspace[iOffs+iVert];
bNotFound=TFALSE;
}
else
++i;
}
assert(!bNotFound);
}
}
}