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import Qt3D.Core 2.0
import Qt3D.Render 2.0

Technique {
    annotations : [
        Annotation { name : "RenderingStyle"; value : "forward"},
        Annotation { name : "Enabled"; value : true}
    ]
    graphicsApiFilter {api : GraphicsApiFilter.OpenGL; profile : GraphicsApiFilter.CoreProfile; minorVersion : 1; majorVersion : 3 }
    renderPasses : [
        RenderPass {
            annotations : [Annotation {name : "Name"; value : "TextureLighting" }]
            bindings : [ // Add only the bindings needed for a shader
                ParameterMapping {parameterName: "vertexTexCoord"; shaderVariableName: "texCoord0"; bindingType: ParameterMapping.Attribute},
                ParameterMapping {parameterName: "tex"; shaderVariableName: "texture"; bindingType: ParameterMapping.Uniform},
                ParameterMapping {parameterName: "modelViewProjection"; shaderVariableName: "customMvp"; bindingType: ParameterMapping.StandardUniform}
            ]

            shaderProgram : ShaderProgram {
                id : textureShaderLighting
                vertexShaderCode: "
                #version 140
                in vec4 vertexPosition;
                in vec3 vertexNormal;
                in vec2 texCoord0;

                out vec2 texCoord;
                out vec3 worldPosition;
                out vec3 normal;

                uniform mat4 customMvp;
                uniform mat4 modelView;
                uniform mat3 modelViewNormal;

                void main()
                {
                    texCoord = texCoord0;
                    worldPosition = vec3(modelView * vertexPosition);
                    normal = normalize(modelViewNormal * vertexNormal);
                    gl_Position  = customMvp * vertexPosition;
                }"

                fragmentShaderCode: "
                #version 140
                in vec2 texCoord;
                in vec3 worldPosition;
                in vec3 normal;
                out vec4 fragColor;

                struct PointLight
                {
                    vec3 position;
                    vec3 direction;
                    vec4 color;
                    float intensity;
                };

                const int lightCount = 3;
                uniform PointLight pointLights[lightCount];
                uniform sampler2D texture;

                void main()
                {
                    vec4 color;
                    for (int i = 0; i < lightCount; i++) {
                        vec3 s = normalize(pointLights[i].position - worldPosition);
                        color += pointLights[i].color * (pointLights[i].intensity * max(dot(s, normal), 0.0));
                    }
                    color /= float(lightCount);
                    fragColor = texture(texture, texCoord) * color;
                }"
            }
        },
        RenderPass {
            annotations : [Annotation {name : "Name"; value : "Texture" }]
            shaderProgram : ShaderProgram {
                vertexShaderCode : "
                #version 140
                in vec4 vertexPosition;
                in vec2 vertexTexCoord;
                out vec2 texCoord;

                uniform mat4 mvp;

                void main()
                {
                    texCoord = vertexTexCoord;
                    gl_Position = mvp * vertexPosition;
                }"

                fragmentShaderCode: "
                #version 140
                in vec2 texCoord;
                out vec4 fragColor;
                uniform sampler2D tex;

                void main()
                {
                    fragColor = texture(tex, texCoord);
                }
                "
            }
        },
        RenderPass {
            annotations : [Annotation {name : "Name"; value : "Lighting" }]
            renderStates : [BlendState {srcRGB: BlendState.One; dstRGB : BlendState.One},
                BlendEquation {mode: BlendEquation.FuncAdd},
                CullFace { mode : CullFace.Back },
                DepthTest { func : DepthTest.LessOrEqual}
            ]
            shaderProgram : ShaderProgram {
                vertexShaderCode: "
                #version 140
                in vec4 vertexPosition;
                in vec3 vertexNormal;

                out vec3 worldPosition;
                out vec3 normal;

                uniform mat4 modelViewProjection;
                uniform mat4 modelView;
                uniform mat3 modelViewNormal;

                void main()
                {
                    worldPosition = vec3(modelView * vertexPosition);
                    normal = normalize(modelViewNormal * vertexNormal);
                    gl_Position = modelViewProjection * vertexPosition;
                }
                "

                fragmentShaderCode: "
                #version 140
                in vec3 worldPosition;
                in vec3 normal;
                out vec4 fragColor;

                struct PointLight
                {
                    vec3 position;
                    vec3 direction;
                    vec4 color;
                    float intensity;
                };

                const int lightCount = 3;
                uniform PointLight pointLights[lightCount];

                void main()
                {
                    vec4 color;
                    for (int i = 0; i < lightCount; i++) {
                        vec3 s = normalize(pointLights[i].position - worldPosition);
                        color += pointLights[i].color * (pointLights[i].intensity * max(dot(s, normal), 0.0));
                    }
                    color /= float(lightCount);
                    fragColor = color;
                }"
            }
        },
        RenderPass {
            annotations : Annotation {name : "Name"; value : "Final" }
            shaderProgram : ShaderProgram {
                vertexShaderCode: "
                #version 140
                in vec4 vertexPosition;
                in vec2 vertexTexCoord;
                out vec2 texCoord;
                uniform mat4 modelViewProjection;

                void main()
                {
                    texCoord = vertexTexCoord;
                    gl_Position = modelViewProjection * vertexPosition;
                }
                "

                fragmentShaderCode: "
                #version 140
                in vec2 texCoord;
                out vec4 fragColor;
                uniform sampler2D gBuffer;

                void main()
                {
                    fragColor = texture(gBuffer, texCoord);
                }
                "
            }
        }

    ]
}