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added parameter theta (from conformal to equiareal) to AreaPresTextureOptimizer. 

Improved feature lists (comments).
This commit is contained in:
mtarini 2007-02-02 04:11:00 +00:00
parent 436c9ae56c
commit 28eb5780f0
1 changed files with 42 additions and 22 deletions
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62
vcg/complex/trimesh/textcoord_optimization.h
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@ -24,6 +24,9 @@
History History
$Log: not supported by cvs2svn $ $Log: not supported by cvs2svn $
Revision 1.5 2007/02/02 01:39:58 tarini
added three general-utility global functions for texture coordinates: SmoothTextureCoords, IsFoldFree, MarkFolds (see descriptions)
Revision 1.4 2007/02/02 01:23:47 tarini Revision 1.4 2007/02/02 01:23:47 tarini
added a few general comments on AreaPreserving optimizer, recapping optimizer features. added a few general comments on AreaPreserving optimizer, recapping optimizer features.
@ -141,20 +144,24 @@ public:
/* /*
AREA PRESERVING TEXTURE OPTIMIZATION AREA PRESERVING TEXTURE OPTIMIZATION
as in DEGENER, P., MESETH, J., AND KLEIN, R. An adaptable surface
parameterization method. [2003] In Proc. of the 12th International Meshing as in: Degener, P., Meseth, J., Klein, R.
Roundtable, 201–213. "An adaptable surface parameterization method."
Proc. of the 12th International Meshing oundtable, 201–213 [2003].
Features: Features:
:) - Balances angle and area distortions (best results!). :) - Balances angle and area distortions (best results!).
:) - Can choose how to balance area and angle preservation (see SetTheta)
theta=0 -> pure conformal (use MIPS instead!)
theta=3 -> good balance between area and angle preservation
theta>3 -> care more about area than about angles
:( - Slowest method. :( - Slowest method.
:( - Requires a fixed boundary, else expands forever in texture space. :( - Requires a fixed boundary, else expands forever in texture space (unless theta=0).
:( - Diverges in presence of flipped faces. :( - Diverges in presence of flipped faces (unless theta=0).
:( - Requires a speed parameter to be set. :( - Requires a speed parameter to be set.
Speed too large => bounces back and forth around minima, w/o getting closer. Speed too large => when close, bounces back and forth around minimum, w/o getting any closer.
Lower speed => longest convercence times Lower speed => longer convercence times
*/ */
template<class MESH_TYPE> template<class MESH_TYPE>
@ -179,12 +186,14 @@ private:
ScalarType totArea; ScalarType totArea;
ScalarType speed; ScalarType speed;
public: int theta;
public:
// constructor and destructor // constructor and destructor
AreaPreservingTextureOptimizer(MeshType &_m):Super(_m),data(_m.face),sum(_m.vert){ AreaPreservingTextureOptimizer(MeshType &_m):Super(_m),data(_m.face),sum(_m.vert){
speed=0.001; speed=0.001;
theta=3;
} }
~AreaPreservingTextureOptimizer(){ ~AreaPreservingTextureOptimizer(){
@ -197,10 +206,23 @@ public:
speed=_speed; speed=_speed;
} }
ScalarType GetSpeed(ScalarType _speed){ ScalarType GetSpeed(){
return speed; return speed;
} }
// sets the parameter theta:
// good parameters are in 1..3
// 0 = converge to pure conformal, ignore area preservation
// 3 = good balance between area and conformal
// >3 = area more important, angle preservation less important
void SetTheta(int _theta){
theta=_theta;
}
int GetTheta(){
return theta;
}
void IterateBlind(){ void IterateBlind(){
/* todo: do as iterate, but without */ /* todo: do as iterate, but without */
Iterate(); Iterate();
@ -213,7 +235,6 @@ public:
#define v0 (f->V0(i)->T().P()) #define v0 (f->V0(i)->T().P())
#define v1 (f->V1(i)->T().P()) #define v1 (f->V1(i)->T().P())
#define v2 (f->V2(i)->T().P()) #define v2 (f->V2(i)->T().P())
#define THETA 3
for (VertexIterator v=Super::m.vert.begin(); v!=Super::m.vert.end(); v++) { for (VertexIterator v=Super::m.vert.begin(); v!=Super::m.vert.end(); v++) {
sum[v].Zero(); sum[v].Zero();
} }
@ -260,24 +281,24 @@ public:
// exponential weighting // exponential weighting
// 2d gradient // 2d gradient
dx=M1*M1 dx=// M1
*(px*(M1+ THETA*M2) - 2.0*qx*M1), //*M1 // ^ theta-1
dy=M1*M1 pow(M1,theta-1)
*(py*(M1+ THETA*M2) - 2.0*qy*M1), *(px*(M1+ theta*M2) - 2.0*qx*M1),
dy=// M1
//*M1 // ^ theta-1
pow(M1,theta-1)
*(py*(M1+ theta*M2) - 2.0*qy*M1),
gy= dy/c, gy= dy/c,
gx= (dx - gy*b) / a; gx= (dx - gy*b) / a;
// 3d gradient // 3d gradient
sum[f->V(i)] sum[f->V(i)]+= ( (v1-v0) * gx + (v2-v0) * gy ) * data[f][3];
//f->V(i)->sum
+= ( (v1-v0) * gx + (v2-v0) * gy ) * data[f][3];
} }
} }
max=0; // max displacement max=0; // max displacement
speed=0.001; speed=0.001;
for (VertexIterator v=Super::m.vert.begin(); v!=Super::m.vert.end(); v++) for (VertexIterator v=Super::m.vert.begin(); v!=Super::m.vert.end(); v++)
if ( !Super::isFixed[v] ) //if (!v->IsB()) if ( !Super::isFixed[v] ) //if (!v->IsB())
@ -294,7 +315,6 @@ public:
#undef v0 #undef v0
#undef v1 #undef v1
#undef v2 #undef v2
#undef THETA
//printf("rejected %d\n",rejected); //printf("rejected %d\n",rejected);
} }