Geometry for Programmers

12 Modeling bodies with images and voxels

This chapter covers

• Understanding 3D images, image masks, and voxels
• Learning the pros and cons of representing 3D models as images
• Using the most common voxel operations, such as erosion and dilation
• Combining voxel operations to create more complex operations
• Making smooth contouring work on images, resulting in an image vectorization algorithm

A 3D image is an image, pretty much like any bitmap but with another dimension. As you can imagine a 2D image as an array of strings in which every string is an array of colored elements, you can imagine a 3D image as an array of 2D images (figure 12.1). 2D images are made of colored squares called pixels, and 3D images are made out of colored cubes called ...