MeshTexture does not render correctly on GPUparticles2D, CPUparticles2D or Polygon2D

[mk56-spn]

Tested versions

• Reproducible in the 4.4 beta.
• Reproducible in 4.1.1 stable.

Honestly i doubt it ever worked given its relatively niche so its feasible it was never brought up ( seems to be the case from an issue search)

System information

Godot v4.4.beta.mono (d004aed08) - Pop!_OS 22.04 LTS on X11 - X11 display driver, Multi-window, 1 monitor - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 4060 Laptop GPU - 12th Gen Intel(R) Core(TM) i7-12650H (16 threads) (this is the branch from this PR : #102028 but the issues are present on other versions too

Issue description

The MeshTexture 2D doesn't display on most the aforementioned nodes. There may be good reasons for this internally but if so it shouldn't show up in the dropdowns imo, or at least throw some sort of error upon attempted assignment

Steps to reproduce

Create a one of the aforementioned nodes, add a MeshTexture to it with it's corresponding mesh and texture. You will be greeted by a blank canvas,

I highly recommend anyone testing this issue test it on #102028 since meshtexture has a plethora of other bugs previous to that that will harm evaluation of this one potentially

Minimal reproduction project (MRP)

MeshParticlesPolygonTest.zip

[beicause]

The 3d model in the MRP is not suitable for MeshTexture, as it does not have appropriate UV. The simplest way to test is using QuadMesh.

[beicause]

Sorry, please ignore my previous comment. I just test the model in #81213, not this MRP.

[mk56-spn]

The most recent changes to #102028 would close this issue / proposal since it is now rendered in a viewport and therefor is a real texture suitable for usage anywhere a normal texture would be a requisite ( barring special cases like point lights that get atlased) , as appears to be the case here