shader_type fog;

uniform vec3 shallow_color : source_color = vec3(0.25, 0.55, 0.70);
uniform vec3 deep_color : source_color = vec3(0.02, 0.05, 0.10);
uniform float surface_y : hint_range(0, 100) = 60.0;
uniform float abyss_y : hint_range(-100, 0) = -60.0;
uniform float base_density : hint_range(0, 1) = 0.04;
uniform float abyss_density : hint_range(0, 3) = 0.25;

void fog() {
	float depth_factor = clamp((surface_y - WORLD_POSITION.y) / (surface_y - abyss_y), 0.0, 1.0);
	vec3 col = mix(shallow_color, deep_color, depth_factor);
	float density = mix(base_density, abyss_density, depth_factor);
	// Subtle current movement
	float wave = sin(WORLD_POSITION.x * 0.1 + TIME * 0.3) * 0.5 + 0.5;
	density *= (0.9 + wave * 0.2);
	ALBEDO = col;
	DENSITY = density;
}