Tribes 2 // Mod Development Handbook GitHub

14 · Terrain texturing

Two tools: one places materials by rule, the other by hand. Use them in that order.

Texture Editor — placement by rule

“The Terrain Texture Editor is used to algorithmically place terrain textures based on the heightfield at the bottom of the terraformer heightfield stack.” [script]

Note what it keys off: the heightfield at the bottom of the terraform stack, not the final applied terrain. Texture rules are evaluated against the generated base, which is why importing terraform rules and texture rules together (File ▸ Import Terraform Data… and Import Texture Data…) reproduces a coherent result.

Three interface elements down the right side [script]:

Element Purpose
Operation inspector pane Parameters of the selected placement operation
Material list The textures in use
Placement operation list The rules that place them

Adding materials

“terrain materials (textures) are added with the Add Material button. This will look for any texture (.png or .jpg) in a subdirectory of any directory named “terrains”.” [script]

So the discovery path is **/terrains/<subdir>/*.png|jpg — which resolves through the mod path stack like everything else (Mod paths and overrides). A mod shipping MyMod/textures/terrains/mymats/rock.png makes that material available in the editor with no registration.

The four placement rules

Rule Places the texture…
Place by Fractal Randomly across the terrain, driven by a Brownian-motion fractal
Place by Height Through an elevation filter
Place by Slope Through a slope filter
Place by Water Level Relative to the water level parameter in the Terraform Editor

These four compose into everything conventional terrain texturing needs:

  • Slope distinguishes cliff faces from ground — the single highest-value rule, because a rock texture on anything steep and grass on anything flat immediately reads as natural.
  • Height gives you snowlines and lowland.
  • Water Level handles shoreline transitions, and takes its parameter from Terraform, so shore texturing follows the water you generated.
  • Fractal breaks up the regularity the other three produce.

Apply commits the operation list to the terrain file.

Texture Painter — manual work

“Users can select up to six different textures in the boxes in the upper right corner of the screen. Selecting a texture will place a black box around it. The terrain brush can then be used to paint the texture on the terrain.” [script]

The brush is the same one as the Terrain Editor — shape, size and hard/soft falloff all carry over (13 · Terrain). Painting is also reachable from the Terrain Editor itself via the Paint Material action mode.

The four-texture rule

The manual’s own warning, and the most important practical constraint in this section [script]:

“Terrains with more than four textures may exhibit rendering irregularities if all those textures are used in the same area of a map. In general it is wise to use four or fewer textures on any individual terrain map.”

So there are three numbers in play and they are not the same:

Limit Value Source
Painter slots 6 Texture Painter UI [script]
makeTestTerrain material arguments 8 Console function signature [binary]
Safe simultaneous textures in one area 4 The manual’s guidance [script]

Design to four. You may define more across a map, but keep any given region to four or fewer, and the rendering stays clean.

Under the QoL patch, the painter is extended from six slots to eight via EPainter::setup, EPainter::onAdd and EPainterChangeMat [patch-script]. Two consequences: a map painted with slots 6–7 will not paint correctly in an unpatched editor, and the four-in-one-area guidance is a rendering constraint that more slots do not remove.

.dml — the material list

Materials are grouped into .dml (DyMaterial List) files — 89 ship in the vanilla archives (File formats). makeTestTerrain takes up to eight of them [binary]:

makeTestTerrain(fileName, {dml1, dml2, ...dml8} );

and echoTerrainTextures() dumps the current set to the console — the quickest way to see what a shipped map actually uses.

Detail texture

Separate from the material set, and set on the TerrainBlock in the .mis [script]:

detailTexture = "details/lushdet2";

The detail texture is a high-frequency overlay applied at close range, independent of which material is underneath. It is what stops terrain looking flat and blurry underfoot. Shipped maps use the per-environment detail textures — lushdet2, and equivalents for desert, ice, lava and badlands.

Custom terrain materials in a mod

If your mod ships terrain textures:

Step Where
Put .png/.jpg under a terrains/ subdirectory MyMod/textures/terrains/mymats/
Group them in a .dml if you want a set Same directory
Clients need the files Textures are referenced by name, not transmitted (Datablocks)

The QoL patch registers a fallback so an unmapped material renders as a flat colour rather than failing [patch-script]:

addMaterialMapping("terrain/default", "color: 0.46 0.36 0.26 0.4 0.0", "sound: 0");

Useful as a safety net; not a substitute for shipping the texture.

Note the "sound:" parameter — terrain materials carry a sound type, which is what selects footstep audio (Armors — LFootSoftSound, LFootHardSound, LFootSnowSound and the rest). Get the material sound wrong and players walk on snow that sounds like metal.