Different Ray-Casting Algorithm Implementations for Volume Rendering

Volume Rendering is the way to achieve 3D visualization. Volume Rendering is used for visualization of 2D projections of 3D data. In volume rendering techniques, direct volume rendering techniques (DVR) can be divided into image order and object order. Image order technique can be achieved by ray-casting algorithm. Ray-casting algorithm is used for raysurface interaction tests to solve problems in computer graphics like collision detection and hidden surface removal. In DVR, the ray is pushed through the object and 3D scalar field of interest is sampled along the ray inside the object. Over the years, different approaches towards this algorithm took place. This paper represents the review and analysis of different approaches of raycasting algorithm

Three-Dimensional Reconstruction of Mechanical Parts Based on Digital Holography

In reconstruction of the off-axis digital hologram of diffuse reflection objects, the position of the positive first-order image cannot be accurately obtained because of the low quality of the reconstruction image. This paper focuses on the above problem and proposes a method for marking the first-order image of the 1-FFT surface based on the fast Fourier transform (1-FFT). The parameters of angle of illumination light were investigated, and the maximum relative measurement error is 5.6% by standard objects. The multiaperture stitching technique in cylindrical coordinates is applied to digital holography technology, and the particle swarm optimization algorithm is used to transform the nonlinear equations into optimization problems to solve the splicing parameters. Finally, the 3D display of a typical rotary three-dimensional mechanical part is successfully realized with holography stitching using the above method.