Generating Terrains via Marching Cube Algorithm for Games

1. Generating Terrains via Marching Cube Algorithm for Games KethanTellisAdam SmithChris BarakianRavi Vaishnav

2. Game Terrains How can we create more interesting game terrains?

3. Game Terrains Methods Height maps

4. Game Terrains Methods Height maps Procedurally Generated

5. Game Terrains Methods Height maps Procedurally Generated Via Geometry Shaders

6. Game Terrains Methods Height maps Procedurally Generated Via Geometry Shaders Scanning Models

7. Game Terrains Methods Drawbacks • Heightmaps • Lack of complexity in environment (No caves / tunnels) • Procedurally Generated • Can’t be saved and reused. Gameplay is inconsistent • Geometry Shaders • Difficulty in collision detection • High computational costs • Scanning Models • Difficult to create • Costly in time and resources

8. Complex, Reusable, Cheap Terrains Perlin Noise Marching Cubes Algorithm

9. PerlinNoise Implementation • Octaves • Number of octaves increases the amount of the jitter around the lowest frequency • Alpha • Increases / Decreases amplitude of certain frequencies, bigger changes in terrains • Beta • Changes how much weight is granted to higher frequencies, more sharp deviations in terrain • Frequency • Amplifies the fluctuations in the amount of jitter

10. PerlinNoise Implementation • Octaves • Number of octaves increases the amount of the jitter around the lowest frequency • Alpha • Increases / Decreases amplitude of certain frequencies, bigger changes in terrains • Beta • Changes how much weight is granted to higher frequencies, more sharp deviations in terrain • Frequency • Amplifies the fluctuations in the amount of jitter

11. PerlinNoise Implementation • Octaves • Number of octaves increases the amount of the jitter around the lowest frequency • Alpha • Increases / Decreases amplitude of certain frequencies, bigger changes in terrains • Beta • Changes how much weight is granted to higher frequencies, more sharp deviations in terrain • Frequency • Amplifies the fluctuations in the amount of jitter

12. Marching Cubes Implementation • Algorithm / Look-Up Table • Actually algorithmically described all 256 cases • Face Normals / Winding Order • Correctly had face normals face away from bounded density areas • Vertex Normals • Achieved weight averaged normalsfor verticiesby comparing to neighbors • OBJ Export • Allowed surface to be exported as OBJ file for loading into Maya and eventually games

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26. Marching Cubes Implementation • Mesh Construction • Built lookup table of each case • Built final mesh by adding position • OpenGL Implementation • Used Vertex Arrays for speed increase • GLSL for custom shading

27. Q & A Demo

28. Q & A Questions?