Terrain¶

Doriax renders large outdoor landscapes with a heightmap-based Terrain object. The terrain uses a clipmap-style LOD grid, so the polygon count on screen stays roughly constant regardless of terrain size, with detail concentrated near the camera.

Terrain anatomy¶

Input	Purpose
Heightmap	Grayscale image that displaces the grid vertically (white = `maxHeight`)
Base texture	The ground texture tiled across the whole terrain
Blend map	RGB mask that mixes up to three detail textures over the base
Detail textures	Red/green/blue channel textures (e.g. grass, rock, path)

Editing terrain in the editor¶

Select an entity with a Terrain component and click Open Terrain Editor in the Properties window. The Terrain Editor provides brush-based authoring:

Tool	Effect
Raise / Lower	Sculpt the heightmap up or down
Smooth	Soften height transitions
Flatten	Level an area to a uniform height
Paint Red / Green / Blue	Paint detail textures into the blend map channels

Brushes have configurable size, strength, shape (circle/square), and falloff.

Creating terrain in code¶

LuaC++

terrain = Terrain(scene)
terrain:setHeightMap("terrain/heightmap.png")
terrain:setTexture("terrain/grass_base.png")

terrain:setBlendMap("terrain/blendmap.png")
terrain:setTextureDetailRed("terrain/rock.png")
terrain:setTextureDetailGreen("terrain/grass_detail.png")
terrain:setTextureDetailBlue("terrain/path.png")

-- Dimensions and LOD are properties in Lua
terrain.size = 2000          -- world units per side
terrain.maxHeight = 80       -- world height of a white heightmap pixel
terrain.resolution = 256     -- heightmap sampling resolution

Terrain terrain(&scene);
terrain.setHeightMap("terrain/heightmap.png");
terrain.setTexture("terrain/grass_base.png");

terrain.setBlendMap("terrain/blendmap.png");
terrain.setTextureDetailRed("terrain/rock.png");
terrain.setTextureDetailGreen("terrain/grass_detail.png");
terrain.setTextureDetailBlue("terrain/path.png");

terrain.setSize(2000.0f);
terrain.setMaxHeight(80.0f);
terrain.setResolution(256);

Terrain derives from Mesh, so material, shadow, and texture APIs from Mesh apply as well.

LOD tuning¶

Property	Controls
`rootGridSize`	Quads per side of each patch — higher = denser geometry
`levels`	Number of LOD rings around the camera — higher = larger view range
`textureBaseTiles`	How many times the base texture repeats across the terrain
`textureDetailTiles`	Repeat count for the detail textures

Start with the defaults; raise levels for very large terrains and rootGridSize when close-up silhouettes look too coarse.

Terrain collision¶

For physics, add a Body3D with a height field shape to the terrain entity — see Physics. Keep the visual resolution and collision resolution consistent so objects rest on the visible surface.