User:Plussai/GSoC 2012 log

7 May 2012

• build the brl-cad svn on VM successfully.
• build the brlcad-7.18.4 on windows(vs2005),but some link error occured from libtclcad.lib

8 May 2012

• get familiar with the Brep structure.

 ON_CurveArray m_C2;//Pointers to parameter space trimming curves (used by trims)

 ON_CurveArray m_C3;//Pointers to 3d curves (used by edges)

 ON_BrepEdgeArray m_E;//edges

 ON_BrepFaceArray m_F;//faces

 ON_BrepLoopArray m_L;//loops

 ON_SurfaceArray m_S;//Pointers to parametric surfaces (used by faces)

 ON_BrepTrimArray m_T;//trims

 ON_BrepVertexArray m_V;//vertexs
 figure:[1]

9 May 2012

• understand some important point about NURBS. 3D NURBS is not tensor product surface,but it can be represented into tensor product surface by mapping 3D NURBS into 4D using homogeneous coordinate.(The NURBS BOOK page 30)
• circle Arc can be represented by vector{(1,1,0,1),(1,1,1,1),(2,0,2,2)}in yz plane