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#include "qsgvivantevideomaterialshader.h"
#include "qsgvivantevideonode.h"
#include "qsgvivantevideomaterial.h"

QSGVivanteVideoMaterialShader::QSGVivanteVideoMaterialShader() :
    mUScale(1),
    mVScale(1),
    mNewUVScale(true)
{
}

void QSGVivanteVideoMaterialShader::updateState(const RenderState &state,
                                                QSGMaterial *newMaterial,
                                                QSGMaterial *oldMaterial)
{
    Q_UNUSED(oldMaterial);

    QSGVivanteVideoMaterial *mat = static_cast<QSGVivanteVideoMaterial *>(newMaterial);
    program()->setUniformValue(mIdTexture, 0);
    mat->bind();
    if (state.isOpacityDirty()) {
        mat->setOpacity(state.opacity());
        program()->setUniformValue(mIdOpacity, state.opacity());
    }
    if (mNewUVScale) {
        program()->setUniformValue(mIdUVScale, mUScale, mVScale);
        mNewUVScale = false;
    }
    if (state.isMatrixDirty())
        program()->setUniformValue(mIdMatrix, state.combinedMatrix());
}

const char * const *QSGVivanteVideoMaterialShader::attributeNames() const {
    static const char *names[] = {
        "qt_VertexPosition",
        "qt_VertexTexCoord",
        0
    };
    return names;
}

void QSGVivanteVideoMaterialShader::setUVScale(float uScale, float vScale)
{
    mUScale = uScale;
    mVScale = vScale;
    mNewUVScale = true;
}

const char *QSGVivanteVideoMaterialShader::vertexShader() const {
    static const char *shader =
            "uniform highp mat4 qt_Matrix;                      \n"
            "attribute highp vec4 qt_VertexPosition;            \n"
            "attribute highp vec2 qt_VertexTexCoord;            \n"
            "varying highp vec2 qt_TexCoord;                    \n"
            "void main() {                                      \n"
            "    qt_TexCoord = qt_VertexTexCoord;               \n"
            "    gl_Position = qt_Matrix * qt_VertexPosition;   \n"
            "}";
    return shader;
}

const char *QSGVivanteVideoMaterialShader::fragmentShader() const {
    static const char *shader =
            "uniform sampler2D texture;"
            "uniform lowp float opacity;"
            "uniform highp vec2 uvScale;"
            ""
            "varying highp vec2 qt_TexCoord;"
            ""
            "void main()"
            "{"
            "  gl_FragColor = vec4(texture2D( texture, qt_TexCoord * uvScale ).rgb, 1.0) * opacity;\n"
            "}";
    return shader;
}


void QSGVivanteVideoMaterialShader::initialize() {
    mIdMatrix = program()->uniformLocation("qt_Matrix");
    mIdTexture = program()->uniformLocation("texture");
    mIdOpacity = program()->uniformLocation("opacity");
    mIdUVScale = program()->uniformLocation("uvScale");
}