AOO410/main/slideshow/source/engine/transitions/spiralwipe.cxx

/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * 
 *************************************************************/



// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_slideshow.hxx"

#include <canvas/debug.hxx>
#include "spiralwipe.hxx"
#include "transitiontools.hxx"

#include <basegfx/matrix/b2dhommatrix.hxx>
#include <basegfx/polygon/b2dpolygon.hxx>
#include <basegfx/numeric/ftools.hxx>
#include <basegfx/matrix/b2dhommatrixtools.hxx>


namespace slideshow {
namespace internal {

SpiralWipe::SpiralWipe( sal_Int32 nElements, bool flipOnYAxis )
    : m_elements(nElements),
      m_sqrtElements( static_cast<sal_Int32>(
                          sqrt( static_cast<double>(nElements) ) ) ),
      m_flipOnYAxis(flipOnYAxis)
{
}

::basegfx::B2DPolyPolygon SpiralWipe::calcNegSpiral( double t ) const
{
    const double area = (t * m_elements);
    const double e = (sqrt(area) / 2.0);
    const sal_Int32 edge = (static_cast<sal_Int32>(e) * 2);
    
    basegfx::B2DHomMatrix aTransform(basegfx::tools::createTranslateB2DHomMatrix(-0.5, -0.5));
    const double edge_ = ::basegfx::pruneScaleValue(
        static_cast<double>(edge) / m_sqrtElements );
    aTransform.scale( edge_, edge_ );
    aTransform.translate( 0.5, 0.5 );
    ::basegfx::B2DPolygon poly( createUnitRect() );
    poly.transform( aTransform );
    ::basegfx::B2DPolyPolygon res(poly);
    
    if (! ::basegfx::fTools::equalZero( 1.0 - t )) {
        const sal_Int32 edge1 = (edge + 1);
        sal_Int32 len = static_cast<sal_Int32>( (e - (edge /2)) * edge1 * 4 );
        double w = M_PI_2;
        while (len > 0) {
            const sal_Int32 alen = (len > edge1 ? edge1 : len);
            len -= alen;
            poly = createUnitRect();
            aTransform = basegfx::tools::createScaleB2DHomMatrix(
                ::basegfx::pruneScaleValue( static_cast<double>(alen) / m_sqrtElements ),
                ::basegfx::pruneScaleValue( 1.0 / m_sqrtElements ) );
            aTransform.translate(
                - ::basegfx::pruneScaleValue(
                    static_cast<double>(edge / 2) / m_sqrtElements ),
                ::basegfx::pruneScaleValue(
                    static_cast<double>(edge / 2) / m_sqrtElements ) );
            aTransform.rotate( w );
            w -= M_PI_2;
            aTransform.translate( 0.5, 0.5 );
            poly.transform( aTransform );
            res.append(poly);
        }
    }
    
    return res;
}

::basegfx::B2DPolyPolygon SpiralWipe::operator () ( double t )
{
    ::basegfx::B2DPolyPolygon res( createUnitRect() );
    ::basegfx::B2DPolyPolygon innerSpiral( calcNegSpiral( 1.0 - t ) );
    innerSpiral.flip();
    res.append(innerSpiral);
    return m_flipOnYAxis ? flipOnYAxis(res) : res;
}

::basegfx::B2DPolyPolygon BoxSnakesWipe::operator () ( double t )
{
    ::basegfx::B2DPolyPolygon res( createUnitRect() );
    ::basegfx::B2DPolyPolygon innerSpiral( calcNegSpiral( 1.0 - t ) );
    innerSpiral.flip();
    
    if (m_fourBox) {
        ::basegfx::B2DHomMatrix aTransform;
        aTransform.scale( 0.5, 0.5 );
        innerSpiral.transform( aTransform );
        res.append(innerSpiral);
        res.append( flipOnXAxis(innerSpiral) );
        innerSpiral = flipOnYAxis(innerSpiral);
        res.append(innerSpiral);
        res.append( flipOnXAxis(innerSpiral) );
    }
    else {
        ::basegfx::B2DHomMatrix aTransform;
        aTransform.scale( 1.0, 0.5 );
        innerSpiral.transform( aTransform );
        res.append(innerSpiral);
        res.append( flipOnXAxis(innerSpiral) );
    }
    
    return m_flipOnYAxis ? flipOnYAxis(res) : res;
}

}
}