Slicing of CAD models in color STL format

Slicing a surface colored model is the basis of forming it by Color Rapid Prototyping. It is also a voxelization process. The procedures for slicing a layer are as below. First, calculate the contour polygon of the intersection of each triangular facet and the layer by 3D polygonal clipping, and then calculate the coordinates of its bounding box. Second, find the boundary voxels intersecting the facet in the bounding box. Third, calculate the area of the contour polygon of the intersection of the facet and each of the boundary voxels intersecting the facet. Finally, for each boundary voxel, find the facet with the contour polygon of the intersection of the facet and the voxel being the largest among all the triangular facets intersecting the voxel, and assign the voxel the same color as that of the facet. The proposed method is applicable to the slicing of CAD models in color STL format. It is also meaningful to the development of the method for slicing CAD models in PLY or VRML format.