Combining texture and shape colors

A texture image may contain:

• A red-green-blue color at each pixel

• A transparency, or alpha value at each pixel

Typically, image color modulates shape color

• Darkly shaded parts of the shape use a darkened texture, etc.

Blending textures using alpha

• Alpha blending is a linear blending from one value to another as alpha goes from 0.0 to 1.0:

  • Value = (1.0-alpha)*Value0 + alpha*Value1

• Texture alpha values can control color blending

• Texture color values can do spectral color filtering, using color as three alpha values