Why Procedural Terrain? Large area exploration Small details - PowerPoint PPT Presentation

Why Procedural Terrain? • Large area  exploration • Small details  interest • Endless worlds (e.g. Minecraft) • Time saving for artists  Procedural generation  Artistic control

Overview 1. Polygonal Map: initial shape 2. Terrain Features: tune the terrain 3. Water Erosion: increase realism 4. Vegetation: add life

Perlin Noise The programmer’s friend

Fractal noise – sum of perlin noise

Step 1: : Polygonal Map

Voronoi diagram

Island shape Perlin noise + distance to the center

Elevation, Temperature, Moisture

Elevation, Temperature, Moisture

Elevation, Temperature, Moisture

Elevation, Temperature, Moisture

Create height map

Step 2: : Terrain Features

Feature Curves Interpolation between Control Points • Elevation • Plateau size • Slope size • Slope angle • Smoothing influence

Hills only elevation and smoothing, no slope

Hills only elevation and smoothing, no slope

Ridge lines 45° slope

Ridge lines 45° slope

Cliffs 90° slope at one side, long smoothing at the other side

Cliffs 90° slope at one side, long smoothing at the other side

Step 3: : Hydraulic Erosion

Pipe model Move water from one cell to another when the height is lower

Erosion Water erodes sediment on steep slopes Sediment is deposited on flat areas

Step 4: : Vegetation

Assign biomes • Texture • Grass density • Tree types

Grass quads with texture

Grass quads with texture

Grass quads with texture

Trees • Define trees recursively • Specify properties for every layer: • Radius, scaling • Curvature • Branching, splitting • Textures

Problem: too many polygons  Use impostors for distant rendering

Thanks for your attention