MRT needs a filter if there are several objects with different shader counts in the scene

[Spiri0]

MRT needs a filter if there are several objects with different shader counts in the scene

[Mugen87]

When you configure in webgl2_multiple_rendertargets the render target with a count of 3, the following WebGL warning in the console appears:

GL_INVALID_OPERATION: Active draw buffers with missing fragment shader outputs.

The issue could be fixed by making sure the object's shader writes data to the new layout(location = 2). Or by not rendering the object at all.

I'm not sure if the engine should automatically handle this use case. It seems to me the the developer instead is responsible to configure its scene correctly. So if you have objects with different shader outputs in your scene, you could

a) create multiple scenes and render them separately with different render targets.
b) use Layers or Object3D.visible and configure the objects with a respective value that you want include/exclude from rendering.

The problem is that objects with non-matching outputs are some sort of invalid input for MRT in the first place. It must be defined how objects are treated if they write e.g. no normal or velocity values and that is an application specific thing.

[Spiri0]

I use different layers. But your comment is correct because that's exactly why I introduced the layers and I use 4 of them.
According to logic there should be no conflicts.

Yesterday I worked more intensively on the readRenderTargetPixels topic. To do this, I have to familiarize myself with webgl much more intensively. I actually only deal with WebGPU

Please take the issue out so I can examine it more intensively with the layers.

I'm juggling with a little too many topics at the moment and am becoming less attentive as a result. I'm usually very thorough with my analyses. I'll slow down a bit.

[Mugen87]

Don't worry! The discussions here at GitHub are also intended to sort out one thoughts.