/*
  ==============================================================================

   This file is part of the JUCE library.
   Copyright (c) 2017 - ROLI Ltd.

   JUCE is an open source library subject to commercial or open-source
   licensing.

   By using JUCE, you agree to the terms of both the JUCE 5 End-User License
   Agreement and JUCE 5 Privacy Policy (both updated and effective as of the
   27th April 2017).

   End User License Agreement: www.juce.com/juce-5-licence
   Privacy Policy: www.juce.com/juce-5-privacy-policy

   Or: You may also use this code under the terms of the GPL v3 (see
   www.gnu.org/licenses).

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

//==============================================================================
/**
    A graphical effect filter that can be applied to components.

    An ImageEffectFilter can be applied to the image that a component
    paints before it hits the screen.

    This is used for adding effects like shadows, blurs, etc.

    @see Component::setComponentEffect

    @tags{Graphics}
*/
class JUCE_API  ImageEffectFilter
{
public:
    //==============================================================================
    /** Overridden to render the effect.

        The implementation of this method must use the image that is passed in
        as its source, and should render its output to the graphics context passed in.

        @param sourceImage      the image that the source component has just rendered with
                                its paint() method. The image may or may not have an alpha
                                channel, depending on whether the component is opaque.
        @param destContext      the graphics context to use to draw the resultant image.
        @param scaleFactor      a scale factor that has been applied to the image - e.g. if
                                this is 2, then the image is actually scaled-up to twice the
                                original resolution
        @param alpha            the alpha with which to draw the resultant image to the
                                target context
    */
    virtual void applyEffect (Image& sourceImage,
                              Graphics& destContext,
                              float scaleFactor,
                              float alpha) = 0;

    /** Destructor. */
    virtual ~ImageEffectFilter() = default;

};

} // namespace juce
