Some methods for shader to solve Blend Alpha

Regarding the problem that Blend Alpha encounters the occlusion error of translucent objects, there are two methods,

The first, the traditional way, in the D3D9 era and on the Android platform, is generally solved by double pass, (AlphaTest + Blend Alpha).

Second, Alpha to Coverage was added after DX10 to replace the previous dual-pass method. After Unity 5.3, the corresponding AlphaToMask in unityshader