Research On The Hardware Voxelization Algorithm For Canonical Volumetric Display

The main research content of this thesis is the hardware voxelization algorithm for canonical volumetric display. Volumetric display is a techonology which can display 3D geometric in real 3D space. It is a true 3D display techonology. The voxels in canonical volumetric display are cubes that uniformly distributed in the cartesian coordinate system. Hardware voxelization algorithm which concerned with converting geometric object from its continuous geometric representation into a set of voxels that best approximates the original one is realized using circuit.First, the Bresenham algorithm of 2D lines and its extension in 3D space is described in this thesis. The hardware Bresenham algorithm which is described with VHDL language for 3D lines is realized in FPGA. Then the parametric equation of cubic Bezier curves is discussed and its integer voxelization algorithm is proposed. Then the hardware voxelization algorithm which based on the integer algorithm is realized in FPGA. The resultes of these hardware voxelization algorithms are stored in a DDR2 SDRAM memory whose capacity is 2GB in this thesis. The corresponding data is read from the memory when a voxels is generated by the hardware voxelization algorithm. Then the exclusive or operation between the voxel data and the corresponding data is done and the result of the operation is written into the memory to realize the generation and erasure of the 3D geometric. The corresponding data is read from the memory to display the 3D geometric according to the state of the canonical volumetric displayer. An operation method which generates and stores 8 voxels together continiously according to the read/write sequence of DDR2 SDRAM memory and the process of the voxelization algorithms is presented. And the computation efficiency increased about 8 times. Then the idea of ping-pang operation is used to gain a higher efficiency. Finnaly, a canonical volumetric display system which is based on these hardware voxelization algorithms is constructed. The real-time generation and display of the grid models of complex 3D geometries which is based on the hardware Bresenham algorithm for 3D lines, cubic Bezier curve voxelization algorithm and Solidworks API etc. are realized. The user guide interface which makes it easy to interact with the volumetric display system is also designed.