Carla/source/modules/juce_gui_basics/buttons/juce_DrawableButton.cpp

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

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2020 - Raw Material Software Limited

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

   For this technical preview, this file is not subject to commercial licensing.

   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
{

DrawableButton::DrawableButton (const String& name, const DrawableButton::ButtonStyle buttonStyle)
    : Button (name), style (buttonStyle)
{
}

DrawableButton::~DrawableButton()
{
}

//==============================================================================
static std::unique_ptr<Drawable> copyDrawableIfNotNull (const Drawable* const d)
{
    if (d != nullptr)
        return d->createCopy();

    return {};
}

void DrawableButton::setImages (const Drawable* normal,
                                const Drawable* over,
                                const Drawable* down,
                                const Drawable* disabled,
                                const Drawable* normalOn,
                                const Drawable* overOn,
                                const Drawable* downOn,
                                const Drawable* disabledOn)
{
    jassert (normal != nullptr); // you really need to give it at least a normal image..

    normalImage     = copyDrawableIfNotNull (normal);
    overImage       = copyDrawableIfNotNull (over);
    downImage       = copyDrawableIfNotNull (down);
    disabledImage   = copyDrawableIfNotNull (disabled);
    normalImageOn   = copyDrawableIfNotNull (normalOn);
    overImageOn     = copyDrawableIfNotNull (overOn);
    downImageOn     = copyDrawableIfNotNull (downOn);
    disabledImageOn = copyDrawableIfNotNull (disabledOn);

    currentImage = nullptr;

    buttonStateChanged();
}

//==============================================================================
void DrawableButton::setButtonStyle (const DrawableButton::ButtonStyle newStyle)
{
    if (style != newStyle)
    {
        style = newStyle;
        buttonStateChanged();
    }
}

void DrawableButton::setEdgeIndent (const int numPixelsIndent)
{
    edgeIndent = numPixelsIndent;
    repaint();
    resized();
}

Rectangle<float> DrawableButton::getImageBounds() const
{
    auto r = getLocalBounds();

    if (style != ImageStretched)
    {
        auto indentX = jmin (edgeIndent, proportionOfWidth  (0.3f));
        auto indentY = jmin (edgeIndent, proportionOfHeight (0.3f));

        if (shouldDrawButtonBackground())
        {
            indentX = jmax (getWidth()  / 4, indentX);
            indentY = jmax (getHeight() / 4, indentY);
        }
        else if (style == ImageAboveTextLabel)
        {
            r = r.withTrimmedBottom (jmin (16, proportionOfHeight (0.25f)));
        }

        r = r.reduced (indentX, indentY);
    }

    return r.toFloat();
}

void DrawableButton::resized()
{
    Button::resized();

    if (currentImage != nullptr)
    {
        if (style != ImageRaw)
        {
            int transformFlags = 0;

            if (style == ImageStretched)
            {
                transformFlags |= RectanglePlacement::stretchToFit;
            }
            else
            {
                transformFlags |= RectanglePlacement::centred;

                if (style == ImageOnButtonBackgroundOriginalSize)
                    transformFlags |= RectanglePlacement::doNotResize;
            }

            currentImage->setTransformToFit (getImageBounds(), transformFlags);
        }
    }
}

void DrawableButton::buttonStateChanged()
{
    repaint();

    Drawable* imageToDraw = nullptr;
    float opacity = 1.0f;

    if (isEnabled())
    {
        imageToDraw = getCurrentImage();
    }
    else
    {
        imageToDraw = getToggleState() ? disabledImageOn.get()
                                       : disabledImage.get();

        if (imageToDraw == nullptr)
        {
            opacity = 0.4f;
            imageToDraw = getNormalImage();
        }
    }

    if (imageToDraw != currentImage)
    {
        removeChildComponent (currentImage);
        currentImage = imageToDraw;

        if (currentImage != nullptr)
        {
            currentImage->setInterceptsMouseClicks (false, false);
            addAndMakeVisible (currentImage);
            resized();
        }
    }

    if (currentImage != nullptr)
        currentImage->setAlpha (opacity);
}

void DrawableButton::enablementChanged()
{
    Button::enablementChanged();
    buttonStateChanged();
}

void DrawableButton::colourChanged()
{
    repaint();
}

void DrawableButton::paintButton (Graphics& g,
                                  const bool shouldDrawButtonAsHighlighted,
                                  const bool shouldDrawButtonAsDown)
{
    auto& lf = getLookAndFeel();

    if (shouldDrawButtonBackground())
        lf.drawButtonBackground (g, *this,
                                 findColour (getToggleState() ? TextButton::buttonOnColourId
                                                              : TextButton::buttonColourId),
                                 shouldDrawButtonAsHighlighted, shouldDrawButtonAsDown);
    else
        lf.drawDrawableButton (g, *this, shouldDrawButtonAsHighlighted, shouldDrawButtonAsDown);
}

//==============================================================================
Drawable* DrawableButton::getCurrentImage() const noexcept
{
    if (isDown())  return getDownImage();
    if (isOver())  return getOverImage();

    return getNormalImage();
}

Drawable* DrawableButton::getNormalImage() const noexcept
{
    return (getToggleState() && normalImageOn != nullptr) ? normalImageOn.get()
                                                          : normalImage.get();
}

Drawable* DrawableButton::getOverImage() const noexcept
{
    if (getToggleState())
    {
        if (overImageOn   != nullptr)   return overImageOn.get();
        if (normalImageOn != nullptr)   return normalImageOn.get();
    }

    return overImage != nullptr ? overImage.get() : normalImage.get();
}

Drawable* DrawableButton::getDownImage() const noexcept
{
    if (auto* d = getToggleState() ? downImageOn.get() : downImage.get())
        return d;

    return getOverImage();
}

} // namespace juce