 u_layer1 = 1
 u_layer2 = 2
 u_layer3 = 3
+u_background_color = [0.965, 0.965, 0.965, 1.0]
 u_outline_strength = 1.0
 u_outline_color = [0.05, 0.66, 0.89, 1.0]
 


    uniform vec2 u_offset[9];

    uniform float u_outline_strength;
    uniform vec4 u_outline_color;


        kernel[3] = 1.0; kernel[4] = -4.0; kernel[5] = 1.0;
        kernel[6] = 0.0; kernel[7] = 1.0; kernel[8] = 0.0;

        vec4 result = u_background_color;
        vec4 layer0 = texture2D(u_layer0, v_uvs);
        vec4 layer2 = texture2D(u_layer2, v_uvs);

