| Value | Meaning |
|---|---|
| sourceTexture0 | Use the texture given as an argument for this function. |
| sourceScreen1 | Use the current viewport's texture as the source. |
| source2dTexture2 | Use the texture from this shader's texture built-in (e.g. a texture of a Sprite). |
| source2dNormal3 | Use the texture from this shader's normal map built-in. |
| sourceDepth4 | Use the depth texture available for this shader. |
| sourcePort5 | Use the texture provided in the input port for this function. |