Unity Shader - Stencil

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Comparison Function ( ex: Comp always )

Greater
Only render pixels whose reference value is greater than the value in the buffer.

GEqual
Only render pixels whose reference value is greater than or equal to the value in the buffer.

Less
Only render pixels whose reference value is less than the value in the buffer.

LEqual
Only render pixels whose reference value is less than or equal to the value in the buffer.

Equal
Only render pixels whose reference value equals the value in the buffer.

NotEqual
Only render pixels whose reference value differs from the value in the buffer.

Always
Make the stencil test always pass.

Never
Make the stencil test always fail.


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Stencil Operation ( ex: Pass replace )
ex: ZFail decrWrap -> comp에 실패한 경우 Ref를 낮춘다.

Keep
Keep the current contents of the buffer.

Zero
Write 0 into the buffer.

Replace
Write the reference value into the buffer.

IncrSat
Increment the current value in the buffer. If the value is 255 already, it stays at 255.

DecrSat
Decrement the current value in the buffer. If the value is 0 already, it stays at 0.

Invert
Negate all the bits.


IncrWrap
Increment the current value in the buffer. If the value is 255 already, it becomes 0.


DecrWrap
Decrement the current value in the buffer. If the value is 0 already, it becomes 255.