Core Concept
A heightfield is a 2D volume (a ZX grid) where every point stores a height value. It isn't classic geometry - it's a volume manipulated by dedicated nodes, converted to polygons only at the end of the pipeline. This companion reference lists the individual nodes; for the full workflow, biome logic and the 3×3 vegetation rule, see Heightfield Terrains, Biomes and Vegetation.
Two volumes coexist at all times: the height layer (altitudes) and the mask layer (zones of influence, values 0-1). Every terrain node reads and writes these two layers.
Basic Pipeline
The Grid Spacing parameter on the HeightField node sets the size of a voxel in meters (resolution). The smaller it is, the more detailed the terrain - and the slower the simulation. Work at a high Grid Spacing during tests, and only lower it for the final render.
Typical chain: HeightField → HeightField Noise → [sculpting / erosion] → HeightField Convert. The Convert step is mandatory before rendering - it turns the volume into polygons; Karma and Mantra don't render heightfield volumes directly.
Generation Nodes
| Node | Role |
|---|---|
| HeightField | Starting point. Generates the flat 2D volume. Key parameters: Size (world scale in meters) and Grid Spacing (resolution/voxel). |
| HeightField Noise | The first node wired in 95% of cases. Adds vertical noise to create the base relief. Controls: Amplitude, Element Size, noise type (Perlin, Worley, Simplex...). |
| HeightField File | Imports an external heightmap - a 2D image, EXR, or RAW file. Used to bring in data from Gaea, World Machine, or real DEM data (USGS, Copernicus). |
| HeightField Project | Projects 3D geometry onto the heightfield. Useful for embedding a rock, a building, or a precise footprint into the terrain. Caution: vertical areas get stretched along the Y axis. |
| HeightField Paint | Manual brush sculpting directly on the terrain or its masks. |
| HeightField Pattern | Adds procedural geometric patterns: ramps, steps, bands, Voronoi cells. |
Sculpting and Modification Nodes
| Node | Role |
|---|---|
| HeightField Blur | Softens the terrain or a mask. Used to smooth transitions or reduce noise artifacts. |
| HeightField Clip | Clamps min/max values - creates plateaus (upper clip) or floors (lower clip). |
| HeightField Remap | Redistributes height values through a curve. Very powerful for flattening zones, exaggerating peaks, or redistributing the overall amplitude. Often underrated - it's frequently what makes the difference between a flat terrain and one with character. |
| HeightField Resample | Changes the volume's resolution. Upres before export, downres for quick tests. |
| HeightField Terrace | Creates terraces/steps from slopes - Andean-style terrain or stepped cliffs. |
| HeightField Slump | Simulates gravity acting on loose material: rockfalls, natural talus slopes, accumulation at the base of slopes. |
Layers and Compositing Nodes
| Node | Role |
|---|---|
| HeightField Layer | Composites two heightfields together (modes: add, subtract, max, min, blend...). |
| HeightField Copy Layer | Duplicates a layer (height or mask) to reuse elsewhere in the network. |
| HeightField Layer Clear | Resets a layer to zero (a fixed value across the whole volume). |
| HeightField Patch | Pastes features from one heightfield onto another - useful for assembling elements generated separately. |
| HeightField Isolate Layer | Copies a layer onto the mask and optionally flattens the height. |
Mask Nodes
Masks are the central system behind biomes. They determine where effects apply and where vegetation is placed. A mask is always a value between 0 (no effect) and 1 (full effect).
| Node | Role |
|---|---|
| HeightField Mask by Feature | Generates a mask from the terrain's own features: slope, altitude, curvature, exposure. The foundation of the biome system and vegetation placement. |
| HeightField Mask by Object | A mask defined by external geometry - useful for placing vegetation inside a manually drawn zone. |
| HeightField Mask by Occlusion | Masks hollow, shadowed areas - riverbeds, valleys, wetlands. |
Output and Utility Nodes
| Node | Role |
|---|---|
| HeightField Convert | Mandatory before rendering. Converts the volume into polygons, VDB, or a polygon soup. |
| HeightField Scatter | Scatters points across the terrain surface. The foundation of procedural vegetation placement. |
| HeightField Output | Exports the heightfield as an image file (for Substance, Gaea, etc.). |
| HeightField Flow Field | Generates flow-direction layers - useful for placing vegetation according to water flow. |
| HeightField Quick Shade | A fast material preview with per-layer textures. For visualizing biomes while working. |
| HeightField Visualize | Visualization via an altitude ramp plus a colored tint for masks. |
| HeightField Tile Split / Splice | Splits and reassembles the terrain into tiles - for distributed rendering or very large terrains. |
Tips
- Tab-menu shortcut - type
hfinstead ofheightfieldto filter directly to all the Heightfield nodes. - High Grid Spacing for tests, low for the final - don't work at high resolution during the design phase.
- Stack several HeightField Noise nodes - one for the overall shape (large Element Size, strong Amplitude), one for detail (small Element Size, low Amplitude).
- HeightField Remap is underrated - it's often what makes the difference between a flat terrain and one with character.
- Always finish with HeightField Convert - Karma and Mantra don't render heightfield volumes directly.