Proximity Fade broken in Compatibility (OpenGL)

[lijon]

Tested versions

• v4.3.dev5.official [89f70e9]

System information

Godot v4.3.dev5 - macOS 13.6.0 - GLES3 (Compatibility) - Apple M1 Pro - Apple M1 Pro (8 Threads)

Issue description

The Proximity Fade in StandardMaterial3D does not work with Compatibility renderer. The produced code assumes Vulkan Z range 0.0 to 1.0 instead of OpenGL -1.0 to 1.0. The fix is to remap the depth_tex as follows:

// Proximity Fade: Enabled
	float depth_tex = textureLod(depth_texture, SCREEN_UV, 0.0).r;
        depth_tex = depth_tex * 2.0 - 1.0; // <-- For OpenGL
	vec4 world_pos = INV_PROJECTION_MATRIX * vec4(SCREEN_UV * 2.0 - 1.0, depth_tex, 1.0);
	world_pos.xyz /= world_pos.w;
	ALPHA *= clamp(1.0 - smoothstep(world_pos.z + proximity_fade_distance, world_pos.z, VERTEX.z), 0.0, 1.0);

Steps to reproduce

• Use Compatibility renderer.
• Add a cube on a plane, or two intersecting cubes, etc.
• Apply a new standardMaterial3D and enable Proximity Fade.

Minimal reproduction project (MRP)

N/A

[jsjtxietian]

Good catch!