Improving Electrical Power Grid Visualization Using Geometry Shaders

The graphics engine of a Power Grids Computer-Aided-Design application was upgraded from Direct3D 9 to Direct3D 11, allowing the use of new features such as the Geometry Shader and Stream Output stages of the graphics pipeline to improve the performance of power grids visualization. Geometry shaders have been used to generate two triangles forming a quadrangle (quad) for each power line, giving it a width as a function of the power load carried by the line. Two implementations were tested: one generating the quads in every draw and other which only generates them once, saving the results to video memory for subsequent draws. Both have been compared with the previous implementation which used vertex shaders. The possibility of using the mentioned pipeline stages to generate levels of detail for the power grids was also studied.