In case you have a seperate opacity map and a base (diffuse/Albedo) map. You'd need to combine them into 1 to use the transparancy in the hdrp lit shader. This does that for you
- Go from this
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- To this
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- place the script in an editor folder (doesn't have to because I wrapped it in Unity_Editor preprocessor directives)
- Make the albedo and opacity map readable/writable.
- Open me by going to Tools/Opacity Albedo Packer
- place the textures in the respective slots
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- Make sure the opacity map has it's transparency properly set up (either set 'Alpha Source' to 'from grayscale' or to 'Input Texture Alpha')
- Either way your preview should show the transparent squares in the preview
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Hit Combine Textures.
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It'll create a new texture with 'combined' at the end.
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- Place this texture in the 'base map' slot.
- Make sure alpha clipping is enabled in the material shader.