diff --git a/tests/domain/material-rendering.test.ts b/tests/domain/material-rendering.test.ts
new file mode 100644
index 00000000..3be7ac33
--- /dev/null
+++ b/tests/domain/material-rendering.test.ts
@@ -0,0 +1,91 @@
+import { describe, expect, it } from "vitest";
+import { NoColorSpace, SRGBColorSpace, Texture } from "three";
+
+import type { LoadedImageAsset } from "../../src/assets/image-assets";
+import {
+  createMaterialSignature,
+  createMaterialTextureSet,
+  disposeMaterialTextureSet
+} from "../../src/materials/material-rendering";
+import { createCustomMaterialDef } from "../../src/materials/starter-material-library";
+
+function createLoadedImageAsset(
+  assetId: string,
+  options: { hasAlpha?: boolean } = {}
+): LoadedImageAsset {
+  return {
+    assetId,
+    storageKey: `project-asset:${assetId}`,
+    metadata: {
+      kind: "image",
+      width: 2,
+      height: 2,
+      hasAlpha: options.hasAlpha ?? false,
+      warnings: []
+    },
+    texture: new Texture(),
+    sourceUrl: `memory://${assetId}`,
+    previewUrl: `memory://${assetId}`,
+    revokeSourceUrl: () => undefined
+  };
+}
+
+describe("material rendering", () => {
+  it("keeps scalar-only custom materials texture-free", () => {
+    const material = createCustomMaterialDef({
+      id: "material-scalar-only",
+      opacity: 0.62,
+      roughness: 0.24,
+      metallic: 0.11
+    });
+    const textureSet = createMaterialTextureSet(material, undefined, {});
+
+    expect(textureSet).toEqual({
+      baseColor: null,
+      normal: null,
+      roughness: null,
+      metallic: null,
+      specular: null,
+      albedoHasAlpha: false
+    });
+    expect(createMaterialSignature(material, {})).toContain("0.62|0.24|0.11");
+  });
+
+  it("lazily clones only referenced custom material maps with slot color spaces", () => {
+    const albedoAsset = createLoadedImageAsset("asset-albedo-alpha", {
+      hasAlpha: true
+    });
+    const normalAsset = createLoadedImageAsset("asset-normal");
+    const material = createCustomMaterialDef({
+      id: "material-textured",
+      textures: {
+        albedo: {
+          assetId: albedoAsset.assetId
+        },
+        normal: {
+          assetId: normalAsset.assetId
+        },
+        roughness: null,
+        metallic: null
+      }
+    });
+
+    const textureSet = createMaterialTextureSet(material, undefined, {
+      [albedoAsset.assetId]: albedoAsset,
+      [normalAsset.assetId]: normalAsset
+    });
+
+    expect(textureSet.baseColor).not.toBeNull();
+    expect(textureSet.normal).not.toBeNull();
+    expect(textureSet.roughness).toBeNull();
+    expect(textureSet.metallic).toBeNull();
+    expect(textureSet.albedoHasAlpha).toBe(true);
+    expect(textureSet.baseColor).not.toBe(albedoAsset.texture);
+    expect(textureSet.baseColor?.colorSpace).toBe(SRGBColorSpace);
+    expect(textureSet.normal?.colorSpace).toBe(NoColorSpace);
+
+    disposeMaterialTextureSet(textureSet);
+    albedoAsset.texture.dispose();
+    normalAsset.texture.dispose();
+  });
+});