Hardware-Based Voxelization for 3 D Spatial Analysis

This paper presents and evaluates a fast graphics hardwarebased voxelization method to spatial analysis, which generates object-coded volume data utilizing the Performer scene-graph. Two color-coding algorithms are introduced. The first one resolves one object per voxel for a large number of objects. The second algorithm extends the first to identify multiple objects in one voxel, by using blending and the stencil buffer. This enables us to simulate the ”object to voxel” behavior of software-based polygon voxelization techniques. The voxelization process utilizes the application window without interfering with the visual part of the application. The results show that the voxelization time is only dependent on the z resolution – the number of slices to be rendered. The comparison of the hardwareand the software-based voxelization method demonstrates that, especially for small resolutions of z, the hardwarebased method is much faster.