Use isColorType for clarity

Signed-off-by: Jonathan Stone <[email protected]>

python/Scripts/creatematerial.py

@@ -177,7 +177,7 @@ def buildDocument(textureFiles, mtlxFile, shadingModel, colorspace, useTiledImag
  imageNode = nodeGraph.addNode(imageNodeCategory, textureName, inputType)
 
  # Set color space.
- if 'color' in inputType.lower():
+ if shaderInput.isColorType():
  imageNode.setColorSpace(colorspace)
 
  # Set file path.