src/Mod/Fem目录下App和Gui子目录是c++函数，其他的子目录为python函数。如果用python编程，如何调用c++函数呢？
我们看下src/Mod/Fem/Gui/ViewProviderFemMesh.cpp, 其中有个applyDisplacementToNodes函数:
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void ViewProviderFemMesh::applyDisplacementToNodes(double factor)
if(DisplacementVector.size() == 0)
return;
float x,y,z;
// set the point coordinates
long sz = pcCoords->point.getNum();
SbVec3f* verts = pcCoords->point.startEditing();
for (long i=0;i < sz ;i++) {
verts[i].getValue(x,y,z);
// undo old factor#
Base::Vector3d oldDisp = DisplacementVector[i] * DisplacementFactor;
x -= oldDisp.x;
y -= oldDisp.y;
z -= oldDisp.z;
// apply new factor
Base::Vector3d newDisp = DisplacementVector[i] * factor;
x += newDisp.x;
y += newDisp.y;
z += newDisp.z;
// set the new value
verts[i].setValue(x,y,z);
}Gui/
pcCoords->point.finishEditing();
DisplacementFactor = factor;
把它开放给python, 需要包装一下。包装函数在src/Mod/Fem/Gui/ViewProviderFemMeshPyImp.cpp里:
Code: Select all
PyObject* ViewProviderFemMeshPy::applyDisplacement(PyObject * args)
double factor;
if (!PyArg_ParseTuple(args, "d", &factor))
return 0;
this->getViewProviderFemMeshPtr()->applyDisplacementToNodes(factor);
Py_Return;
这样c++的applyDisplacementToNodes函数变成了python的applyDisplacement函数。
python中对这个函数的调用可以看femguiobjects\_ViewProviderFemResultMechanical.py:
Code: Select all
def update_displacement(self, factor=None):
if factor is None:
if FreeCAD.FEM_dialog["show_disp"]:
factor = self.result_widget.sb_displacement_factor.value()
else:
factor = 0.0
self.mesh_obj.ViewObject.applyDisplacement(factor)
这样你就可以用c++写一些功能，然后在python里调用了。
