Implement RasterizedMeshTexture (RenderingDevice)

[beicause]

• Implement and close Add support for rasterizing mesh to texture with custom shader godot-proposals#12443

Ported from https://github.com/beicause/GodotMeshTextureRd (very different now).

Current MeshTexture is just a wrapper for canvas_item_add_mesh() and doesn't store texture data itself, which means it can't be used in shader uniform or 3D scene. And it can't do regional drawing.

This PR implements a more powerful rasterized mesh texture, which provides more flexible control than the MeshTexture. And should have better performance compared to ViewportTexture (#102028).

RasterizedMeshTexture reads one surface from mesh and supports shader material (both vertex shader and fragment shader) with the new shader type "rasterize_mesh".

This is only implemented in RenderingDevice (Forawrd+&Mobile renderer) for now, not Compatibility.

[mk56-spn]

The latest commit seems to induce a crash when attempting to rotate the 3d preview for the mesh. this appear to be a regression from the version from before the force push 8991649 to cf91792 which did not in my testing suffer from this

[beicause]

The latest commit seems to induce a crash when attempting to rotate the 3d preview for the mesh. this appear to be a regression from the version from before the force push 8991649 to cf91792 which did not in my testing suffer from this

I couldn't reproduce the crash on Linux. However I tested on Windows and found it throws errors and can't run at all. (Fixed now, and it doesn't crash, either).
Could you provide more detailed information on how to reproduce it?

[mk56-spn]

The latest commit seems to induce a crash when attempting to rotate the 3d preview for the mesh. this appear to be a regression from the version from before the force push 8991649 to cf91792 which did not in my testing suffer from this

I couldn't reproduce the crash on Linux. However I tested on Windows and found it throws errors and can't run at all. (Fixed now, and it doesn't crash, either). Could you provide more detailed information on how to reproduce it?

2025-05-17.12-07-33.mp4

hey here are all the steps to repro this

and here is my specs in case. im also on linux

Godot v4.5.dev.mono (59a9f4c) - 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)

fwiw moving the main window also seems to cause a crash. weird

[beicause]

Are you able to compile with dev_build=yes to get a backtrace? I can't reproduce Vulkan 1.4.305 - Forward+ - Using Device #0: AMD - AMD Radeon Graphics (RADV RENOIR)

[CarpenterBlue]

I have encountered crash when trying to copy paste the node between scenes.

godot.windows.editor.dev.x86_64_8BCCvefFns.mp4

[CarpenterBlue]

And another crash when I try to remove the material.

godot.windows.editor.dev.x86_64_2JHCZwxR2C.mp4

[beicause]

I have encountered crash when trying to copy paste the node between scenes.
And another crash when I try to remove the material.

Fixed now.

[CarpenterBlue]

Perfect, I can confirm it's no longer crashing but when I add a shader, the texture stops showing up.
I also tried undo and redo and it still lived without an issue.

godot.windows.editor.x86_64_wCui41KOOc.mp4

[beicause]

but when I add a shader, the texture stops showing up.

It's because the projection is actually zero matrix until modifying or reloading the scene. I opened a separate issue #106561

[beicause]

You can also modify the ww component to globally scale.

[CarpenterBlue]

You can also modify the ww component to globally scale.

I did not realized that but that makes total sense.

[beicause]

Implemented drawable texture in my opinion that works with the mesh rasterizer. See also godotengine/godot-proposals#12443 (comment)

In addition:

• Custom blend state via RasterizerBlendState (almost the same with RDPipelineColorBlendStateAttachment).
• All possiable RD texture format that supported by Godot.
• MSAA.

TODO:
Waiting for more feedback and unify this PR with #105701. As I focus on RD render and not familiar with compatibility renderer, not sure if these features are suitable for compatibility renderer.

In addition, this PR chooses to do nothing for the conversion between sRGB and linear( source_color hint also does nothing ). There is a difference in RGBAF/RGBAH texture colors in the 2D and 3D renderers. But RGBA8/RGBA8_SRGB textures displays the same in 2D and 3D. I think it's expected.

Test project:

rasterized-mesh-tex (2).zip

And use mesh rasterizer with https://github.com/Auburn/FastNoiseLite/blob/master/GLSL/FastNoiseLite.glsl:

shader_type mesh_rasterizer;

uniform vec2 size = vec2(256,256);
uniform int noise_seed = 0;

#include "include/FastNoiseLite.gdshaderinc"

void fragment() {
	fnl_state state = fnlCreateState(noise_seed);
	state.noise_type = FNL_NOISE_OPENSIMPLEX2;
	state.fractal_type = FNL_FRACTAL_FBM;
	state.frequency = 0.01f;
	state.octaves = 4;
	state.lacunarity = 2.0f;
	state.gain = 0.5f;

	FNLfloat val = fnlGetNoise2D(state, UV.x*size.x, UV.y*size.y)/ 2.0f + 0.5f;
	COLOR = vec4(val, 0.0, 0.0, 1.0);
}

[beicause]

Pushed a simplified implementation (just a single texture_drawable_draw_mesh to draw, no separate mesh_rasterizer rid), and it completely avoids processing mesh on CPU. However, this means the mesh matrix needs to be manually adjusted otherwise the default position may be not good.

Removed blend state and MSAA settings.