Unity3D:Graphics.BlitMultiTap method

In the study of the "Graphics.blitmultitap method and Shaderlab class shader multi-mapping study" code, found that the GRAPHICS.BLITMULTITAP function is not very understanding, Baidu is actually found good wen " Graphics.blitmultitap method and multi-mapping study of Shaderlab class shader, share here.

The most important words are as follows:

proves that it is true that every time SetTexture can acquire a new multi-texture layer and coordinates, this kind of implicit passing way really kills people ...
So the system blureffect the shader, even if the Blitmultitap specified more than 4 offsets, can only mix up to 4 layers, because shader wrote Dead 4 times SetTexture, This blitmultitap is not as good as it should be.

This is exactly how Graphics.blitmultitap and blureffect work completely: Using the OPEGGL multi-texturing feature, the multi-layer map with hardware support in a pass is offset and mixed with different coordinates. It's just that the official never has the data to mention that the original shader each settexture corresponds to BLITMULTITAP incoming a set of offsets coordinates, shader code to see people foggy.

This means that the number of vector2d arrays in the Blitmultitap parameter is matched to the number of settexture in the shader of the parameter material.

Unity3D:Graphics.BlitMultiTap method