Raytracing based Renderer for Sphere-Packings

This thesis is about the implementation of a raytracing based renderer for sphere-packings, called ProtoRender.


The renderer uses different methods inside the raytracing approach. These methods range from simple ray-casting using only one ray per pixel to pathtracing, using multiple rays and multiple samples. Performance-tests on these methods were conducted using a broad range of computer-systems to gather meaningful data. Acceleration structures were implemented at varying degrees with optional visualizers to dynamically witness the integration of these structures. Additionally some attempts were made to render Metaballs. Generally, rendering is based on a tiled approach across all algorithms to provide a stable and highly configurable experience. Tiling in this case means that the algorithm divides the image into chunks to avoid long periods of GPU unresponsiveness.


A renderer with multiple rendering and acceleration techniques was implemented. The rendering methods are both useful for quick visualizations or for creating presentable images. The performance in the raycasting approach is good enough for interactive rendering while the pathtracing approach takes longer. However, combining these two methods (e.g. use a fast shader to position the camera and then use a slower, but more realistic shader to make the final render) yields a good user-experience as well as good looking images. Experiments with Metaballs show interesting results and may prove to be a good starting point for future work.

The pathtracing algorithm produces the best image quality but is relatively slow. A comparison between low and high sample rates can be seen down below.

The pictures below depict some visualization shaders for the acceleration structures. The first two pics visualize a grid, the last pic a BVH.

Finally a column chart which shows the render-time difference between pathtracing with and without acceleration using different sphere counts:


Full version of the bachelor thesis (English only)


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