/********************************************************************
 KWin - the KDE window manager
 This file is part of the KDE project.

Copyright (C) 2007 Rivo Laks <rivolaks@hot.ee>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program 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.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*********************************************************************/

#include "demo_wavywindows.h"

#include <math.h>


namespace KWin
{

KWIN_EFFECT(demo_wavywindows, WavyWindowsEffect)

WavyWindowsEffect::WavyWindowsEffect()
{
    mTimeElapsed = 0.0f;
}


void WavyWindowsEffect::prePaintScreen(ScreenPrePaintData& data, int time)
{
    // Adjust elapsed time
    mTimeElapsed += (time / 1000.0f);
    // We need to mark the screen windows as transformed. Otherwise the whole
    //  screen won't be repainted, resulting in artefacts
    data.mask |= PAINT_SCREEN_WITH_TRANSFORMED_WINDOWS;

    effects->prePaintScreen(data, time);
}

void WavyWindowsEffect::prePaintWindow(EffectWindow* w, WindowPrePaintData& data, int time)
{
    // This window will be transformed by the effect
    data.setTransformed();
    // Check if OpenGL compositing is used
    // Request the window to be divided into cells which are at most 30x30
    //  pixels big
    data.quads = data.quads.makeGrid(30);

    effects->prePaintWindow(w, data, time);
}

void WavyWindowsEffect::paintWindow(EffectWindow* w, int mask, QRegion region, WindowPaintData& data)
{
    // Make sure we have OpenGL compositing and the window is vidible and not a
    //  special window
// TODO    if ( w->isVisible() && !w->isSpecialWindow() )
    if (!w->isSpecialWindow()) {
        // We have OpenGL compositing and the window has been subdivided
        //  because of our request (in pre-paint pass)
        // Transform all the vertices to create wavy effect
        for (int i = 0;
                i < data.quads.count();
                ++i)
            for (int j = 0;
                    j < 4;
                    ++j) {
                WindowVertex& v = data.quads[ i ][ j ];
                v.move(v.x() + sin(mTimeElapsed + v.originalY() / 60 + 0.5f) * 10,
                       v.y() + sin(mTimeElapsed + v.originalX() / 80) * 10);
            }
    }

    // Call the next effect.
    effects->paintWindow(w, mask, region, data);
}

void WavyWindowsEffect::postPaintScreen()
{
    // Repaint the workspace so that everything would be repainted next time
    effects->addRepaintFull();

    // Call the next effect.
    effects->postPaintScreen();
}

} // namespace