// NOTE: Shader automatically converted from Godot Engine 4.3.stable's StandardMaterial3D.

shader_type spatial;
render_mode blend_mix, depth_draw_opaque, cull_back, diffuse_burley, specular_schlick_ggx;


uniform sampler2D spray_texture;
uniform sampler2D lifetime_gradient;
varying vec4 passtrough;

void vertex() {
	passtrough = INSTANCE_CUSTOM;

	// Billboard Mode: Particles
	mat4 mat_world = mat4(
			normalize(INV_VIEW_MATRIX[0]),
			normalize(INV_VIEW_MATRIX[1]),
			normalize(INV_VIEW_MATRIX[2]),
			MODEL_MATRIX[3]);
	mat_world = mat_world * mat4(
			vec4(cos(INSTANCE_CUSTOM.x), -sin(INSTANCE_CUSTOM.x), 0.0, 0.0),
			vec4(sin(INSTANCE_CUSTOM.x), cos(INSTANCE_CUSTOM.x), 0.0, 0.0),
			vec4(0.0, 0.0, 1.0, 0.0),
			vec4(0.0, 0.0, 0.0, 1.0));
	MODELVIEW_MATRIX = VIEW_MATRIX * mat_world;

	// Billboard Keep Scale: Enabled
	MODELVIEW_MATRIX = MODELVIEW_MATRIX * mat4(
			vec4(length(MODEL_MATRIX[0].xyz), 0.0, 0.0, 0.0),
			vec4(0.0, length(MODEL_MATRIX[1].xyz), 0.0, 0.0),
			vec4(0.0, 0.0, length(MODEL_MATRIX[2].xyz), 0.0),
			vec4(0.0, 0.0, 0.0, 1.0));

	MODELVIEW_NORMAL_MATRIX = mat3(MODELVIEW_MATRIX);

	//passtrough = INSTANCE_CUSTOM;
}

void fragment() {
	ROUGHNESS = 0.2;

	vec2 uv = UV * 2.0 - COLOR.xy + (texture(spray_texture, UV * 1.5 + TIME * 0.2 + COLOR.xy * 4.0).zz - (TIME * 0.3)) * 0.2;
	float mist = texture(spray_texture, UV*0.7 + TIME*0.2 - COLOR.xy).x * sin(pow(passtrough.y, 8.0)*PI);
	float foam = (texture(spray_texture, uv).y -0.5) * 2.0 * sin(pow(passtrough.y, 0.5)*PI);
	float mask = max(0, pow((1.3 - length(0.5-UV)*2.5), 2.0-passtrough.y));
	//ALPHA = min(1.0, max(0, texture(spray_texture, UV*0.7 - TIME*0.5 - COLOR.xy).x * sin(pow(passtrough.y, 4.0)*PI) + texture(spray_texture, uv).y -0.5) * 2.0 * sin(pow(passtrough.y, 0.3)*PI) * max(0, pow((1.3 - length(0.5-UV) * 2.0), 1.0+passtrough.y)));
	ALPHA = min(1.0, max(0.0, (foam + mist) * mask));
	ALBEDO = texture(lifetime_gradient, vec2(passtrough.y, 0.5)).xyz;
	BACKLIGHT = ALBEDO;
	//EMISSION = COLOR.xyz * max(0, (1.5-pow(passtrough.y, 0.3)*2.0));
}