/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

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 * License, v. 2.0. If a copy of the MPL was not distributed with this

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 *

 * This file incorporates work covered by the following license notice:

 *

 *   Licensed to the Apache Software Foundation (ASF) under one or more

 *   contributor license agreements. See the NOTICE file distributed

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 *   ownership. The ASF licenses this file to you under the Apache

 *   License, Version 2.0 (the "License"); you may not use this file

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#pragma once

#include <drawinglayer/drawinglayerdllapi.h>

#include <drawinglayer/primitive2d/BufferedDecompositionPrimitive2D.hxx>

#include <drawinglayer/attribute/fillgradientattribute.hxx>

// predefines

namespace basegfx { class B2DPolygon; }

// FillGradientPrimitive2D class

namespace drawinglayer::primitive2d

{

        /** FillGradientPrimitive2D class

            This class defines a gradient filling for a rectangular area. The

            Range is defined by the Transformation, the gradient by the FillGradientAttribute.

            The decomposition will deliver the decomposed gradient, e.g. for an ellipse

            gradient the various ellipses in various color steps will be created.

            I have added functionality to create both versions of filled decompositions:

            Those who overlap and non-overlapping ones. The overlapping version is the

            default one since it works with and without AntiAliasing. The non-overlapping

            version is used in the MetafilePrimitive2D decomposition when the old XOR

            paint was recorded.

            SDPR: Have now added to directly support alpha in the definition so that

            all implementations of primitive renderers may use it. Be aware that if a

            renderer does not support using that alpha it is advised to use the

            decomposition which separates content and alpha in a TransparencePrimitive2D.

            That way all stuff being used to that before will work unchanged.

         */

        class DRAWINGLAYER_DLLPUBLIC FillGradientPrimitive2D : public BufferedDecompositionPrimitive2D

        {

        private:

            /// the geometrically visible area

            basegfx::B2DRange                       maOutputRange;

            /// the area the gradient definition is based on

            /// in the simplest case identical to OutputRange

            basegfx::B2DRange                       maDefinitionRange;

            /// the gradient definition

            attribute::FillGradientAttribute        maFillGradient;

            /// evtl. fitting alphaGradient definition

            attribute::FillGradientAttribute        maAlphaGradient;

            /// the transparency in range [0.0 .. 1.0]

            double mfTransparency;

        protected:

            /// local helper

            Primitive2DReference createFill(bool bOverlapping) const;

            /// local decomposition.

            virtual Primitive2DReference create2DDecomposition(const geometry::ViewInformation2D& rViewInformation) const override;

        public:

            /// helpers that support e.g. direct paint/geometry creation

            basegfx::B2DPolygon getUnitPolygon() const;

            basegfx::BColor getOuterColor() const;

            void generateMatricesAndColors(

                std::function<void(const basegfx::B2DHomMatrix& rMatrix, const basegfx::BColor& rColor)> aCallback) const;

            /// constructors. The one without definition range will use output range as definition range

            FillGradientPrimitive2D(

                const basegfx::B2DRange& rOutputRange,

                const attribute::FillGradientAttribute& rFillGradient);

            FillGradientPrimitive2D(

                const basegfx::B2DRange& rOutputRange,

                const basegfx::B2DRange& rDefinitionRange,

                const attribute::FillGradientAttribute& rFillGradient,

                const attribute::FillGradientAttribute* pAlphaGradient = nullptr,

                double fTransparency = 0.0);

            /// data read access

            const basegfx::B2DRange& getOutputRange() const { return maOutputRange; }

            const basegfx::B2DRange& getDefinitionRange() const { return maDefinitionRange; }

            const attribute::FillGradientAttribute& getFillGradient() const { return maFillGradient; }

            const attribute::FillGradientAttribute& getAlphaGradient() const { return maAlphaGradient; }

            bool hasAlphaGradient() const { return !maAlphaGradient.isDefault(); }

            double getTransparency() const { return mfTransparency; }

            bool hasTransparency() const { return !basegfx::fTools::equalZero(mfTransparency); }

            /// compare operator

            virtual bool operator==(const BasePrimitive2D& rPrimitive) const override final;

            /// get range

            virtual basegfx::B2DRange getB2DRange(const geometry::ViewInformation2D& rViewInformation) const override final;

            /// provide unique ID

            virtual sal_uInt32 getPrimitive2DID() const override final;

        };

} // end of namespace drawinglayer::primitive2d

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