After loading a level, open Edit → Materials to launch the Material Editor. It edits the level's visual/render materials — texture samplers, ubershader features, and shader parameters stored under that level's RENDERABLE data (e.g. LEVEL_MODELS.MTL / LEVEL_MODELS.CST).

This is separate from Physical Materials (collision / Havok surface types under Configurations). The Material Editor is about how things look.

The same window can also open as a picker (with Use This Material) from places like renderable instances, the Material Mapping Editor, and Model Editor import.

The left list shows materials for the loaded level, grouped by ubershader type. Use Search / Clear to filter, then select a material to edit it on the right. Edits apply in memory immediately (Viewport and other views that use the material can update without waiting for a disk save).

The footer shows the material's Ubershader Type (read-only).

Samplers

Each material can reference textures through sampler slots (up to 12). Tabs list the sampler names for that ubershader — a bold tab usually means a texture is assigned.

• Edit Texture… / Pick Texture… — opens the Texture Editor so you can choose or change the texture (level or global).
• Clear Texture — removes the assignment from that slot.

A preview and reference details (sampler index, texture name/format, and so on) appear below when a texture is set.

Features

Feature checkboxes toggle ubershader feature flags for the material's shader. Which options appear depends on the ubershader type — unsupported or unmapped features won't show.

Parameters

Parameters expose pixel-shader constants for the material (floats, vectors, colours). Colour-like parameters (names containing colour/tint, etc.) get a colour preview and Pick Color….

Only parameters that the shader maps into the material's constant buffer are listed.

There isn't a blank “new material” action. To create a variant, select a material and click Duplicate Selected Material. The clone is named with a Clone suffix so you can tune samplers/features/parameters independently.

Duplicates start from the same shader setup as the original — change what you need on the clone rather than assuming every shared field is fully isolated.

The Material Editor has no separate Save button. Persist changes with File → Save Level (Ctrl+S). That writes the level's material (and related) files back to disk.

Saving closes the game if it's running so install files aren't locked.

• Texture Editor — browse and assign textures used by material samplers
• Material Mapping Editor — From→To remaps for materials in the level (separate from editing a material's look)
• Model Editor — model preview/import can use material data and open the Material Editor as a picker
• Physical Materials — collision/surface types (MATERIALS.BML), not visual MTL materials