Terrain

Korender supports optimized rendering of large terrain surfaces by implementing an algorithm based on the idea of Geometry Clipmaps. This algorithm allows to drastically reduce the number of triangles required to render a large terrain while minimizing visual details loss and LOD transitions. Basically, Korender draws the terrain as the series of clipmap rings centered at the viewpoint. Rings represent LOD levels — the more distant the ring is, the coarser triangles it contains. Transitions between rings are smoothed using vertex morphing, which eliminates vertex popping during viewport moving.

To render a terrain, use HeightField within a Frame context:

Frame {
    HeightField(id = "terrain", cellSize = 2.0f, hg = 10, rings = 6) {
        colorTexture = texture("terrain/diffuse.png")
        heightTexture(
            heightTexture = texture("terrain/heightmap.png"),
            heightScale = 200.0f,
            outsideHeight = 0.0f,
            terrainCenter = Vec3(0f, 300f, 0f)
        )
    }
}

HeightField parameters:

Parameter	Type	Default	Description
id	String	—	Unique identifier
cellSize	Float	—	World space size of a terrain cell
hg	Int	—	Parameter defining ring width: the higher the value, the more geometry details are preserved
rings	Int	—	Number of clipmap rings
block	TerrainMaterialScope.() -> Unit	—	Terrain material configuration

The visible terrain extent from the viewpoint is roughly 2 * hg * 2^rings terrain cells.

The block configures the terrain material via TerrainMaterialScope, which extends BaseMaterialScope with all its properties (color, colorTexture, normalTexture, metallicFactor, roughnessFactor, etc.) plus the following:

Method	Parameters	Description
heightTexture	heightTexture: TextureDeclaration, heightScale: Float, outsideHeight: Float = 0f, terrainCenter: Vec3 = Vec3.ZERO	Configures the heightmap: texture (uses red channel for elevation), world-space height scale, fallback height outside texture, and world-space center point