/****************************************************************************+ −
**+ −
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).+ −
** All rights reserved.+ −
** Contact: Nokia Corporation (qt-info@nokia.com)+ −
**+ −
** This file is part of the test suite of the Qt Toolkit.+ −
**+ −
** $QT_BEGIN_LICENSE:LGPL$+ −
** No Commercial Usage+ −
** This file contains pre-release code and may not be distributed.+ −
** You may use this file in accordance with the terms and conditions+ −
** contained in the Technology Preview License Agreement accompanying+ −
** this package.+ −
**+ −
** GNU Lesser General Public License Usage+ −
** Alternatively, this file may be used under the terms of the GNU Lesser+ −
** General Public License version 2.1 as published by the Free Software+ −
** Foundation and appearing in the file LICENSE.LGPL included in the+ −
** packaging of this file. Please review the following information to+ −
** ensure the GNU Lesser General Public License version 2.1 requirements+ −
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.+ −
**+ −
** In addition, as a special exception, Nokia gives you certain additional+ −
** rights. These rights are described in the Nokia Qt LGPL Exception+ −
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.+ −
**+ −
** If you have questions regarding the use of this file, please contact+ −
** Nokia at qt-info@nokia.com.+ −
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** $QT_END_LICENSE$+ −
**+ −
****************************************************************************/+ −
#include "utils.h"+ −
+ −
#include <assert.h>+ −
#include <qglobal.h>+ −
+ −
#include "qnum.h"+ −
+ −
#define FloatToXFixed(i) (int)((i) * 65536)+ −
#define IntToXFixed(i) ((i) << 16)+ −
+ −
static double compute_x_at(XFixed y, XPointFixed p1, XPointFixed p2)+ −
{+ −
double d = XFixedToDouble(p2.x - p1.x);+ −
return+ −
XFixedToDouble(p1.x) + d*XFixedToDouble(y - p1.y)/XFixedToDouble(p2.y - p1.y);+ −
}+ −
+ −
double compute_area(XTrapezoid *trap)+ −
{+ −
double x1 = compute_x_at(trap->top, trap->left.p1, trap->left.p2);+ −
double x2 = compute_x_at(trap->top, trap->right.p1, trap->right.p2);+ −
double x3 = compute_x_at(trap->bottom, trap->left.p1, trap->left.p2);+ −
double x4 = compute_x_at(trap->bottom, trap->right.p1, trap->right.p2);+ −
+ −
double top = XFixedToDouble(trap->top);+ −
double bottom = XFixedToDouble(trap->bottom);+ −
double h = bottom - top;+ −
+ −
double top_base = x2 - x1;+ −
double bottom_base = x4 - x3;+ −
+ −
if ((top_base < 0 && bottom_base > 0)+ −
|| (top_base > 0 && bottom_base < 0)) {+ −
double y0 = top_base*h/(top_base - bottom_base) + top;+ −
double area = qAbs(top_base * (y0 - top) / 2.);+ −
area += qAbs(bottom_base * (bottom - y0) /2.);+ −
return area;+ −
}+ −
+ −
+ −
return 0.5 * h * qAbs(top_base + bottom_base);+ −
}+ −
+ −
double compute_area_for_x(const QVector<XTrapezoid> &traps)+ −
{+ −
double area = 0;+ −
+ −
for (int i = 0; i < traps.size(); ++i) {+ −
XTrapezoid trap = traps[i];+ −
area += compute_area(&trap);+ −
}+ −
return area;+ −
}+ −