Godot fluid shader using flex engine

godot_fluid_shader

shader_type spatial;
render_mode blend_mix, unshaded;

uniform float water_transparency = 0.1;
uniform vec4 water_color: hint_color;
uniform float water_distortion = 20;
uniform vec2 water_distortion_direction = vec2(0, 1);


vec4 blur(sampler2D tex, vec2 current_uv, vec2 pixel_size, int passes ){

	vec2 uv;
	vec4 color = vec4(0.0);

	int c = 0;

	for(int i = 1; i <= passes; ++i){

		float f_i = float(i);
		//float factor = 5.0 - pow((f_i / float(passes)), 0.3) * 5.0;
		float factor = (f_i / float(passes));

		uv = current_uv + pixel_size * vec2(1, 0) * f_i;
		if( uv.x >= 0.0 && uv.y >= 0.0 && uv.x <= 1.0 && uv.y <= 1.0 ){
			vec4 t = texture(tex, uv);
			if(t.a >= 0.0){
				color += texture(tex, uv) * factor;
				c++;
			}
		}

		uv = current_uv + pixel_size * vec2(-1, 0) * f_i;
		if( uv.x >= 0.0 && uv.y >= 0.0 && uv.x <= 1.0 && uv.y <= 1.0 ){
			vec4 t = texture(tex, uv);
			if(t.a >= 0.0){
				color += texture(tex, uv) * factor;
				c++;
			}
		}

		uv = current_uv + pixel_size * vec2(0, 1) * f_i;
		if( uv.x >= 0.0 && uv.y >= 0.0 && uv.x <= 1.0 && uv.y <= 1.0 ){
			vec4 t = texture(tex, uv);
			if(t.a >= 0.0){
				color += texture(tex, uv) * factor;
				c++;
			}
		}

		uv = current_uv + pixel_size * vec2(0, -1) * f_i;
		if( uv.x >= 0.0 && uv.y >= 0.0 && uv.x <= 1.0 && uv.y <= 1.0 ){
			vec4 t = texture(tex, uv);
			if(t.a >= 0.0){
				color += texture(tex, uv) * factor;
				c++;
			}
		}

	}

	if( c > 0 )
		return color / float(c);
	return vec4(0);
}


void fragment(){

	/// Documentation:
	///
	/// vec4 extracted_normal_and_depth = texture(FLUID_NORMAL_DEPTH_TEXTURE, FLUID_SCREEN_UV);
	/// vec4 extracted_tickness = texture(FLUID_THICKNESS_TEXTURE, FLUID_SCREEN_UV);
	/// FLUID_NORMAL = extracted_normal_and_depth.xyz;
	/// FLUID_DEPTH = extracted_normal_and_depth.w;
	/// FLUID_THICKNESS = extracted_tickness.x;


	/// Note:
	/// Before use these please blur 

	float clamped_fluid_thickness = min(FLUID_THICKNESS, 1.0);
	vec4 normal_depth = blur(FLUID_NORMAL_DEPTH_TEXTURE, SCREEN_UV, SCREEN_PIXEL_SIZE, 5);
	vec3 _normal = normal_depth.rgb;
	float _depth = normal_depth.a;

	vec2 uv = SCREEN_UV;
	// Light distortion along plane
	uv += SCREEN_PIXEL_SIZE * clamped_fluid_thickness * water_distortion_direction * water_distortion * 4.0;
	// Light distortion along border
	uv += SCREEN_PIXEL_SIZE * pow(1.0 - _normal.y, 4.) * water_distortion_direction * water_distortion;

	vec3 light_color = vec3(1);
	vec3 shadow_color = vec3(0);

	vec3 color = texture(SCREEN_TEXTURE, uv).rgb;

	color = mix(color, light_color, clamp(pow(_normal.y - 0.53, 0.4), 0, 1));
	color = mix(shadow_color, color, clamp(pow(_normal.y + 0.45, 0.4), 0, 1));
	color = mix(color, water_color.rgb, min(pow(_depth + 0.5, 7.0), 1.0));

	ALBEDO = color;
	ALPHA = 1.0;
}