Transparency

Is about rendering objects that are not fully opaque.

Problems rendering transparent objects #

1. Opaque objects all have to be rendered before the transparent objects

2. There is not one depth that corresponds to a pixel

3. The render order matters

   

How it is done #

• Use Alpha Blending
• Transparent objects should not write into the depth buffer
  1. First all non-transparent objects should be rendered with the normal depth buffer
  2. Then transparent objects should be ordered either back to front or front to back without modifying the depth buffer

Implementations #

• Sort objects by depth and use Alpha Blending
• Per-Pixel Linked Lists
• Depth Peeling