The following tables and images show how mesh simplification, specifically converting large Uniform Grids into Triangulated Irregular Networks, can significantly reduce rendering time with only a slight decrease in model quality. The mesh simplification algorithm can reduce the mesh to a specified quantity or quality goal. For a quantity goal, the number of triangles or the number of vertices can be specified. For a quality goal, the average or maximum vertical error can be specified.
| Ethiopia Model | Original Model - Uniform Grid | Simplified Model - Triangulated Irregular Network |
|---|---|---|
| Number of Vertices | 262,144 | 5,079 (1.93 %) |
| Number of Triangles | 522,242 | 10,000 (1.914 %) |
| Average Vertical Error | 0.0 | 0.0916 (0.34 %) |
| Maximum Vertical Error | 0.0 | 0.2843 (1.07 %) |
| Drawing Time for Textured Model(O2 R10000, 128MB RAM) | 1.798 seconds | 0.068 seconds (3.78 %) |
| Mesh Simplification Time (O2 R10000, 128MB Ram) | n/a | 22 seconds |
The following two images show a wireframe and texture model of the Ethiopia data set.
| Grand_Canyon-west Digital Elevation Model from the USGS | Original Model - Uniform Grid | Simplified Model - Triangulated Irregular Network |
|---|---|---|
| Number of Vertices | 1,442,401 | 14480 (1 %) |
| Number of Triangles | 2,880,000 | 28800 (1 %) |
| Average Vertical Error | 0.0 | 0.037 (0.93 %) |
| Maximum Vertical Error | 0.0 | 0.134 (3.33 %) |
| Drawing Time For Wireframe (O2 R10000, 128MB RAM) | 3.453 seconds | 0.132 seconds |
| Mesh Simplification Time (O2 R10000, 128MB Ram) | n/a | 164 |
The following image shows the Triangulated Irregular Network model of the Grand Canyon model.
| Hurricane Andrew Model | Original Model - Uniform Grid | Simplified Model - Triangulated Irregular Network | Another Triangulated Irregular Network |
|---|---|---|---|
| Number of Vertices | 1,048,576 | 50,000 (4.77 %) | 10,000 (0.95 %) |
| Number of Triangles | 2,093,058 | 99,896 (4.77 %) | 19.958 (0.95 %) |
| Average Vertical Error | 0.0 | 0.026 (0.56 %) | 0.107 (2.23 %) |
| Maximum Vertical Error | 0.0 | 0.176 (3.66 %) | 0.754 (15.65 %) |
| Drawing Time for Textured Model(O2 R10000, 128MB RAM) | 6.9 seconds | 0.663 (9.6 %) | 0.144 seconds (0.208 %) |
| Mesh Simplification Time (O2 R10000, 128MB Ram) | n/a | 180 seconds | 173 seconds |
The followin two images show wireframe and texture map modes for Hurricane andrew with 10,000 vertices.
| Hurricane Fran Model | Original Model - Uniform Grid | Simplified Model - Triangulated Irregular Network |
|---|---|---|
| Number of Vertices | 466,804 | 25,000 (5.36 %) |
| Number of Triangles | 930,860 | 49,835 (5.35 %) |
| Average Vertical Error | 0.0 | 0.111 (1.75 %) |
| Maximum Vertical Error | 0.0 | 0.367 (5.77 %) |
| Drawing Time for Textured Model(O2 R10000, 128MB RAM) | 2.987seconds | 0.316 seconds (10.579 %) |
| Mesh Simplification Time (O2 R10000, 128MB Ram) | n/a | 73 seconds |
The following two images show wireframe and texture map modes for Hurricane Fran.
