Articles - Using superblack transparency

Superblack transparency will turn black parts of a texture transparent. This can be useful in creating shapes with textures. For example a realistic tree can be created by using an image of a tree that has non tree parts black. For example:



When the texture is assigned to a GLScene object with superblack transparency turned on black parts are transparent:



To set a material to use superblack transparency set the TGLMaterial blending mode to bmTransparent and the TGLTexture imagealpha to tiaSuperblackTransparency and load the image. Also having TGLTexture texturemode as tmReplace seems to be necessary aswell. It is best to save the superblack transparent image in TGA format or BMP format since JPG format isn't lossless and you'll see an ugly black line around your texture if you save it in JPG format.

by skinhat