Ok, currently there are two plausible variants on the table:
First solution - Two spinners
- One spinner for material opacity/amount
- One spinner for mask influence
- If no mask is present in mask slot, mask spinner will become frozen
- If mask is present, mask spinner will blend between mask influence and material amount value
The question here is. If we are blending between mask influence and material amount, do we want to blend between absolute value of the mask (from black to white) and the material amount, OR between mask multiplied by the material amount and the material amount without mask.
Practical example: We have one material layer with material amount set to 50%, and this layer has black and white checkerboard mask:
Option 1: Mask amount 0% will mean material amount is used and mask is ignored. Mask amount of 100% will mean black and white checkerboard mask is used, and on white parts of the mask, our material layer is showing 100%, on black parts, layer is completely transparent
Option 2: Mask amount 0% will mean material amount is used and mask is ignored. Mask amount of 100% will mean black and white checkerboard is multiplied by material amount, so that white parts of the mask show our material 50% opaque, black parts show material. So basically mask will never make layer more opaque than what material amount spinner is set to
Second solution: Spinner and a checkbox
- Spinner will be controlling amount of material layer opacity
- If material layer mask is present, spinner will act as a multiplier of mask map
- Checkbox will simply disable entire material layer, rendering it completely transparent regardless of mask or amount value.