2016 Volume 24 Issue 4 Pages 690-699
The theory of general relativity predicts that the strong gravity of a black hole bends the trajectories of light rays. Calculating their bendings numerically, we can obtain a 3D CG image when the view point is set in the black hole spacetime. The existing researches adopt the ray tracing method for rendering while we adopt the rasterization method in this paper. In order to achieve fast perspective projection in the curved spacetime, we calculate more than thirty million light trajectories on an optimally constructed computational mesh in advance and let a GPU interpolate them when rendering. Furthermore, in order to render the lines and triangular polygons of CG objects accurately, we apply the dynamic subdividing technique (tessellation). Various types of CG programs can be easily written in the same way as in the conventional 3D CG programming with a common graphics API. Utilizing the recent computing power of the GPU, the rendering performance of nearly one million polygons per second is achieved even on a notebook PC.