Unity Shaders and Effects Cookbook中的Photoshop levels effect
这个shader写完了之后就是这样的。Shader"Custom/2_6Photoshoplevelseffect"{Properties{_MainTex("Base(RGB)",2D)="white"{}_inBlack("InputBlack",Range(0,255))=0_inGamma("InputGamma",Range(0,2))=1.61_inWhite("InputWhite"