What is new about raster masks?

So far, I have not discovered the difference between using raster masks and using the mask manager in DT. Both offer a convenient way to re-use a previously designed mask. However, I have so far only done this with drawn masks, but I assume there’s no difference.

For drawn masks it doesn’t matter. Raster masks matter when you use a parametric mask and then want to reuse the same mask in another module.

  1. Performance : reusing shapes involves re-cumputing the same mask for as many modules are using them. Raster masks are computed only once and re-used as-is.
  2. Lazyness : when using advanced masking with boolean operations, using raster masks inherits all the boolean ops too and saves you the trouble to reset them later.
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ThAnk you Aurelien! Great advice. What is a boolean op? I know about the principle of boolean algebra but could you give me an example of a boolean mask op?

https://darktable-org.github.io/dtdocs/module-reference/utility-modules/darkroom/mask-manager/#set-operators

Thank you, that’s awesome! I didn’t know about the grouping option in masks. That opens up new opportunities.