JUCE/modules/juce_gui_basics/native/juce_MultiTouchMapper.h

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

   This file is part of the JUCE library.
   Copyright (c) 2015 - ROLI Ltd.

   Permission is granted to use this software under the terms of either:
   a) the GPL v2 (or any later version)
   b) the Affero GPL v3

   Details of these licenses can be found at: www.gnu.org/licenses

   JUCE is distributed in the hope that it will be useful, but WITHOUT ANY
   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
   A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

   ------------------------------------------------------------------------------

   To release a closed-source product which uses JUCE, commercial licenses are
   available: visit www.juce.com for more information.

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

#pragma once

template <typename IDType>
class MultiTouchMapper
{
public:
    MultiTouchMapper() {}

    int getIndexOfTouch (IDType touchID)
    {
        jassert (touchID != 0); // need to rethink this if IDs can be 0!

        int touchIndex = currentTouches.indexOf (touchID);

        if (touchIndex < 0)
        {
            for (touchIndex = 0; touchIndex < currentTouches.size(); ++touchIndex)
                if (currentTouches.getUnchecked (touchIndex) == 0)
                    break;

            currentTouches.set (touchIndex, touchID);
        }

        return touchIndex;
    }

    void clear()
    {
        currentTouches.clear();
    }

    void clearTouch (int index)
    {
        currentTouches.set (index, 0);
    }

    bool areAnyTouchesActive() const noexcept
    {
        for (int i = currentTouches.size(); --i >= 0;)
            if (currentTouches.getUnchecked(i) != 0)
                return true;

        return false;
    }

private:
    Array<IDType> currentTouches;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (MultiTouchMapper)
};