material {
    name : Image,
    parameters : [
        {
            type : sampler2d,
            name : image
        },
        {
            type : mat4,
            name : transform,
            precision : high
        },
        {
            type : float3,
            name : backgroundColor
        },
        {
            type : int,
            name : showImage
        }
    ],
    variables : [
        imageUV
    ],
    vertexDomain : device,
    depthWrite : false,
    shadingModel : unlit,
    variantFilter : [ skinning, shadowReceiver, vsm ],
    culling: none
}

vertex {
    void materialVertex(inout MaterialVertexInputs material) {
        material.imageUV.st = getPosition().st * 0.5 + 0.5;
    }
}

fragment {
    void material(inout MaterialInputs material) {
        prepareMaterial(material);

        vec4 bg = vec4(materialParams.backgroundColor, 1.0);
        highp vec2 uv = (materialParams.transform * vec4(saturate(variable_imageUV.st), 1.0, 1.0)).st;
        if (materialParams.showImage == 0 || uv.s > 1.0 || uv.s < 0.0 || uv.t < 0.0 || uv.t > 1.0) {
            material.baseColor = bg;
        } else {
            uv.t = 1.0 - uv.t;
            vec4 color = max(texture(materialParams_image, uv.st), 0.0);
            color.rgb *= color.a;
            // Manual, pre-multiplied srcOver with opaque destination optimization
            material.baseColor.rgb = color.rgb + bg.rgb * (1.0 - color.a);
        }
    }
}