Thanks for the clarification. Unfortunately your task is not trivial. Bullet hole decals are easier in comparison, as they are typically just additional geometry overlaid onto existing static geometry by adding additional triangles on top of the hit surface.
Depending on how you would want to implement your solution, it would be equivalent to painting to the texture of a 3D model in Substance Painter. So the task would be to invert texture uv mapping, transforming the blob center position to texture space. Perhaps you can find something on the Unity Asset Store like this package (I didn't check whether this asset can be applied in your case).
There are other approaches for modifying blending of textures, often based on vertex colors (like e.g. this asset). However, in your case it is not a static mesh but a dynamic one, so this will not be a viable solution here.
An easier solution could be to use a vector based approach, storing e.g. a maximum of 10 impact center positions and the impact radius. In a custom pixel shader you can then evaluate whether the pixel lies within any of the disk areas.
Another solution would be to use the stencil buffer as a mask buffer. You could then attach your impact disk GameObject to the bone of the hit attachment, and then render the impact disk into the stencil buffer only. Then you can use your custom shader to render your object damaged where the stencil buffer is > 0.
The easiest solution would be to have predefined damage for e.g. 4 directions and enable them by switching the Attachment at the Slot, or overlay a damage Attachment.
In case anyone has other suggestions that I did not think of, I would be happy to hear them. :nerd:
