Billboarding not working when building with precision=double

[joao-pedro-braz]

Godot version

v4.1.dev.custom_build [1e0194a]

System information

Linux X11, Vulkan, Forward+, RX6600XT

Issue description

This behavior can be noticed when building the engine with double precision (precision=double).

Comparison between 4.1.dev (double precision) and 4.0.stable (single precision):

4.1.dev (with double precision)

4.0.stable (with single precision)

According to my testing, the following bit on "scene_forward_clustered.glsl" is responsible for this behavior:

Code for reference:

// We separate the basis from the origin because the basis is fine with single point precision.
// Then we combine the translations from the model matrix and the view matrix using emulated doubles.
// We add the result to the vertex and ignore the final lost precision.
vec3 model_origin = model_matrix[3].xyz;
if (is_multimesh) {
	vertex = mat3(matrix) * vertex;
	model_origin = double_add_vec3(model_origin, model_precision, matrix[3].xyz, vec3(0.0), model_precision);
}
vertex = mat3(model_matrix) * vertex;
vec3 temp_precision; // Will be ignored.
vertex += double_add_vec3(model_origin, model_precision, scene_data.inv_view_matrix[3].xyz, view_precision, temp_precision);
vertex = mat3(scene_data.view_matrix) * vertex;

Removing it and leaving the "else" path as the default gets rid of this behavior:

Code for reference:

vertex = (modelview * vec4(vertex, 1.0)).xyz;

CC-ing @clayjohn as per @Calinou request on Rocket.Chat

Steps to reproduce

Build from master with precision=double, create a scene and add a MeshInstance3D with any mesh whose Material has "billboard" enabled (both "enabled" and "Y-Billboard" fails)

Minimal reproduction project

Can be reproduced using godot-demo-projects#894.