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+ fix undefined behaviour in determining grid length for planar meshes

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wmayer 2015-11-16 11:59:41 +01:00
parent 629a89218d
commit 4f4d747968
1 changed files with 40 additions and 38 deletions
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78
src/Mod/Mesh/App/Core/Grid.cpp
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@ -261,48 +261,50 @@ void MeshGrid::Position (const Base::Vector3f &rclPoint, unsigned long &rulX, un
void MeshGrid::CalculateGridLength (unsigned long ulCtGrid, unsigned long ulMaxGrids)
{
// Grid Laengen bzw. Anzahl der Grids pro Dimension berechnen
// pro Grid sollen ca. 10 (?!?!) Facets liegen
// bzw. max Grids sollten 10000 nicht ueberschreiten
Base::BoundBox3f clBBMeshEnlarged = _pclMesh->GetBoundBox();
float fVolElem;
// Grid Laengen bzw. Anzahl der Grids pro Dimension berechnen
// pro Grid sollen ca. 10 (?!?!) Facets liegen
// bzw. max Grids sollten 10000 nicht ueberschreiten
Base::BoundBox3f clBBMeshEnlarged = _pclMesh->GetBoundBox();
float fGridLen = 0;
// Stelle sicher, dass die Bounding box ein Volumen > 0 besitzt
float fLenX = clBBMeshEnlarged.LengthX();
float fLenY = clBBMeshEnlarged.LengthY();
float fLenZ = clBBMeshEnlarged.LengthZ();
float fMax = 0.005 * std::max<float>(std::max<float>(fLenX, fLenY), fLenZ);
// Falls Bounding box zu einem Punkt degeneriert ist
if (fMax == 0) {
_ulCtGridsX = 1;
_ulCtGridsY = 1;
_ulCtGridsZ = 1;
return;
}
if (fLenX == 0) {
clBBMeshEnlarged.MinX -= fMax;
clBBMeshEnlarged.MaxX += fMax;
}
if (fLenY == 0) {
clBBMeshEnlarged.MinY -= fMax;
clBBMeshEnlarged.MaxY += fMax;
}
if (fLenZ == 0) {
clBBMeshEnlarged.MinZ -= fMax;
clBBMeshEnlarged.MaxZ += fMax;
}
float fLenX = clBBMeshEnlarged.LengthX();
float fLenY = clBBMeshEnlarged.LengthY();
float fLenZ = clBBMeshEnlarged.LengthZ();
if (_ulCtElements > (ulMaxGrids * ulCtGrid))
fVolElem = (clBBMeshEnlarged.LengthX() * clBBMeshEnlarged.LengthY() * clBBMeshEnlarged.LengthZ()) / float(ulMaxGrids * ulCtGrid);
else
fVolElem = (clBBMeshEnlarged.LengthX() * clBBMeshEnlarged.LengthY() * clBBMeshEnlarged.LengthZ()) / float(_ulCtElements);
float fVolume = fLenX * fLenY * fLenZ;
if (fVolume > 0.0f) {
float fVolElem;
if (_ulCtElements > (ulMaxGrids * ulCtGrid))
fVolElem = (fLenX * fLenY * fLenZ) / float(ulMaxGrids * ulCtGrid);
else
fVolElem = (fLenX * fLenY * fLenZ) / float(_ulCtElements);
float fVol = fVolElem * float(ulCtGrid);
float fGridLen = float(pow((float)fVol,(float) 1.0f / 3.0f));
float fVol = fVolElem * float(ulCtGrid);
fGridLen = float(pow(fVol, 1.0f / 3.0f));
}
else {
// Planare Bounding box
float fArea = fLenX * fLenY + fLenX * fLenZ + fLenY * fLenZ;
float fAreaElem;
if (_ulCtElements > (ulMaxGrids * ulCtGrid))
fAreaElem = fArea / float(ulMaxGrids * ulCtGrid);
else
fAreaElem = fArea / float(_ulCtElements);
_ulCtGridsX = std::max<unsigned long>((unsigned long)(clBBMeshEnlarged.LengthX() / fGridLen), 1);
_ulCtGridsY = std::max<unsigned long>((unsigned long)(clBBMeshEnlarged.LengthY() / fGridLen), 1);
_ulCtGridsZ = std::max<unsigned long>((unsigned long)(clBBMeshEnlarged.LengthZ() / fGridLen), 1);
fGridLen = sqrt(fAreaElem * float(ulCtGrid));
}
if (fGridLen > 0) {
_ulCtGridsX = std::max<unsigned long>(static_cast<unsigned long>(fLenX / fGridLen), 1);
_ulCtGridsY = std::max<unsigned long>(static_cast<unsigned long>(fLenY / fGridLen), 1);
_ulCtGridsZ = std::max<unsigned long>(static_cast<unsigned long>(fLenZ / fGridLen), 1);
}
else {
// Degenerated grid
_ulCtGridsX = 1;
_ulCtGridsY = 1;
_ulCtGridsZ = 1;
}
}
void MeshGrid::CalculateGridLength (int iCtGridPerAxis)