Question about Material Override with Property Blocks

[errant jay]

Hey there! I've got a quick question about material handling... Our game has very flat materials with no textures, so we end up getting tons of materials that are only meant for colors. It was getting a little difficult to manage so many colors so I ended up writing a little script where you can set diferent colors with a material property block like:

rend.GetPropertyBlock(s_block,i);
s_block.SetColor(s_color, _colorInfos[i].MatColor);
s_block.SetFloat(s_max, _colorInfos[i].MaxFloat);
rend.SetPropertyBlock(s_block,i);

Now we only have one base material, and we can change the color freely for each object.

My question is... Can this affect badly the render pipeline? I have also activated GPU Instancing as they are all using the same shader/material now. I have done some testing and it seems fine 🤔 But maybe I'm missing some deep knowledge ahaha

Thank you for your time!

[lost ginkgo]

This is the kind of optimization you'd do without SRP batching

[errant jay]

Oh! Without?

[lost ginkgo]

But SRP batching is probably better

[lost ginkgo]

SRP batching is not compatible with MPBs or with GPU instancing
With it you'd make more materials, or runtime instances of materials
Since you're setting MPBs from code, creating material instances from code would not be a different workflow

GPU instancing has an overhead cost so it's best to use it when you have a lot of the same mesh, though in my tests SRP batching beats it even with thousands of meshes

Without any of its limitations

[errant jay]

I see, this is actually just to ease the development as there are not a lot of materials lying around now, but If I can have an optimization boost I will take it too ahah

[errant jay]

Yeah I have read about that... I didn't know SRP batching was that good though!

[lost ginkgo]

I think the way you define variants using MPBs in code would be practically the same as defining variants as materials instead
As long as you keep in mind that material instances exist in memory and should be destroyed when the object also is / when not needed

(by variants as materials I don't mean "material variants" which are an editor UX thing that lets materials inherit properties of parent materials with their own overrides, maybe that helps too)

[errant jay]

Thanks for the insights, it has been very helpful! Material instances are destroyed automatically right?

[lost ginkgo]

You should do that manually on OnDestroy, or when not needed
Afaik the instances remain floating until you have unloaded the scene otherwise

Destroying or unloading the scene they're from sends them to the Garbage Collector, which is better than letting them take up memory but you can re-use material instances as well if you do object pooling to avoid the GC cost