blob: e5cecc833d004f903629943d2f632a23435ecbe7 [file] [log] [blame]
/*
* Copyright (C) 2006 Zack Rusin <zack@kde.org>
* 2006 Rob Buis <buis@kde.org>
* 2009 Dirk Schulze <krit@webkit.org>
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "Path.h"
#include "TransformationMatrix.h"
#include "FloatRect.h"
#include "GraphicsContext.h"
#include "ImageBuffer.h"
#include "PlatformString.h"
#include "StrokeStyleApplier.h"
#include <QPainterPath>
#include <QTransform>
#include <QString>
#include <wtf/OwnPtr.h>
#define _USE_MATH_DEFINES
#include <math.h>
#ifndef M_PI
# define M_PI 3.14159265358979323846
#endif
namespace WebCore {
Path::Path()
: m_path(new QPainterPath())
{
}
Path::~Path()
{
delete m_path;
}
Path::Path(const Path& other)
: m_path(new QPainterPath(*other.platformPath()))
{
}
Path& Path::operator=(const Path& other)
{
if (&other != this) {
delete m_path;
m_path = new QPainterPath(*other.platformPath());
}
return *this;
}
bool Path::contains(const FloatPoint& point, WindRule rule) const
{
Qt::FillRule savedRule = m_path->fillRule();
m_path->setFillRule(rule == RULE_EVENODD ? Qt::OddEvenFill : Qt::WindingFill);
bool contains = m_path->contains(point);
m_path->setFillRule(savedRule);
return contains;
}
bool Path::strokeContains(StrokeStyleApplier* applier, const FloatPoint& point) const
{
ASSERT(applier);
// FIXME: We should try to use a 'shared Context' instead of creating a new ImageBuffer
// on each call.
OwnPtr<ImageBuffer> scratchImage = ImageBuffer::create(IntSize(1, 1));
GraphicsContext* gc = scratchImage->context();
QPainterPathStroker stroke;
applier->strokeStyle(gc);
QPen pen = gc->pen();
stroke.setWidth(pen.widthF());
stroke.setCapStyle(pen.capStyle());
stroke.setJoinStyle(pen.joinStyle());
stroke.setMiterLimit(pen.miterLimit());
stroke.setDashPattern(pen.dashPattern());
stroke.setDashOffset(pen.dashOffset());
return (stroke.createStroke(*platformPath())).contains(point);
}
void Path::translate(const FloatSize& size)
{
QTransform matrix;
matrix.translate(size.width(), size.height());
*m_path = (*m_path) * matrix;
}
FloatRect Path::boundingRect() const
{
return m_path->boundingRect();
}
FloatRect Path::strokeBoundingRect(StrokeStyleApplier* applier)
{
// FIXME: We should try to use a 'shared Context' instead of creating a new ImageBuffer
// on each call.
OwnPtr<ImageBuffer> scratchImage = ImageBuffer::create(IntSize(1, 1));
GraphicsContext* gc = scratchImage->context();
QPainterPathStroker stroke;
if (applier) {
applier->strokeStyle(gc);
QPen pen = gc->pen();
stroke.setWidth(pen.widthF());
stroke.setCapStyle(pen.capStyle());
stroke.setJoinStyle(pen.joinStyle());
stroke.setMiterLimit(pen.miterLimit());
stroke.setDashPattern(pen.dashPattern());
stroke.setDashOffset(pen.dashOffset());
}
return (stroke.createStroke(*platformPath())).boundingRect();
}
void Path::moveTo(const FloatPoint& point)
{
m_path->moveTo(point);
}
void Path::addLineTo(const FloatPoint& p)
{
m_path->lineTo(p);
}
void Path::addQuadCurveTo(const FloatPoint& cp, const FloatPoint& p)
{
m_path->quadTo(cp, p);
}
void Path::addBezierCurveTo(const FloatPoint& cp1, const FloatPoint& cp2, const FloatPoint& p)
{
m_path->cubicTo(cp1, cp2, p);
}
void Path::addArcTo(const FloatPoint& p1, const FloatPoint& p2, float radius)
{
FloatPoint p0(m_path->currentPosition());
if ((p1.x() == p0.x() && p1.y() == p0.y()) || (p1.x() == p2.x() && p1.y() == p2.y()) || radius == 0.f) {
m_path->lineTo(p1);
return;
}
FloatPoint p1p0((p0.x() - p1.x()), (p0.y() - p1.y()));
FloatPoint p1p2((p2.x() - p1.x()), (p2.y() - p1.y()));
float p1p0_length = sqrtf(p1p0.x() * p1p0.x() + p1p0.y() * p1p0.y());
float p1p2_length = sqrtf(p1p2.x() * p1p2.x() + p1p2.y() * p1p2.y());
double cos_phi = (p1p0.x() * p1p2.x() + p1p0.y() * p1p2.y()) / (p1p0_length * p1p2_length);
// all points on a line logic
if (cos_phi == -1) {
m_path->lineTo(p1);
return;
}
if (cos_phi == 1) {
// add infinite far away point
unsigned int max_length = 65535;
double factor_max = max_length / p1p0_length;
FloatPoint ep((p0.x() + factor_max * p1p0.x()), (p0.y() + factor_max * p1p0.y()));
m_path->lineTo(ep);
return;
}
float tangent = radius / tan(acos(cos_phi) / 2);
float factor_p1p0 = tangent / p1p0_length;
FloatPoint t_p1p0((p1.x() + factor_p1p0 * p1p0.x()), (p1.y() + factor_p1p0 * p1p0.y()));
FloatPoint orth_p1p0(p1p0.y(), -p1p0.x());
float orth_p1p0_length = sqrt(orth_p1p0.x() * orth_p1p0.x() + orth_p1p0.y() * orth_p1p0.y());
float factor_ra = radius / orth_p1p0_length;
// angle between orth_p1p0 and p1p2 to get the right vector orthographic to p1p0
double cos_alpha = (orth_p1p0.x() * p1p2.x() + orth_p1p0.y() * p1p2.y()) / (orth_p1p0_length * p1p2_length);
if (cos_alpha < 0.f)
orth_p1p0 = FloatPoint(-orth_p1p0.x(), -orth_p1p0.y());
FloatPoint p((t_p1p0.x() + factor_ra * orth_p1p0.x()), (t_p1p0.y() + factor_ra * orth_p1p0.y()));
// calculate angles for addArc
orth_p1p0 = FloatPoint(-orth_p1p0.x(), -orth_p1p0.y());
float sa = acos(orth_p1p0.x() / orth_p1p0_length);
if (orth_p1p0.y() < 0.f)
sa = 2 * piDouble - sa;
// anticlockwise logic
bool anticlockwise = false;
float factor_p1p2 = tangent / p1p2_length;
FloatPoint t_p1p2((p1.x() + factor_p1p2 * p1p2.x()), (p1.y() + factor_p1p2 * p1p2.y()));
FloatPoint orth_p1p2((t_p1p2.x() - p.x()), (t_p1p2.y() - p.y()));
float orth_p1p2_length = sqrtf(orth_p1p2.x() * orth_p1p2.x() + orth_p1p2.y() * orth_p1p2.y());
float ea = acos(orth_p1p2.x() / orth_p1p2_length);
if (orth_p1p2.y() < 0)
ea = 2 * piDouble - ea;
if ((sa > ea) && ((sa - ea) < piDouble))
anticlockwise = true;
if ((sa < ea) && ((ea - sa) > piDouble))
anticlockwise = true;
m_path->lineTo(t_p1p0);
addArc(p, radius, sa, ea, anticlockwise);
}
void Path::closeSubpath()
{
m_path->closeSubpath();
}
#define DEGREES(t) ((t) * 180.0 / M_PI)
void Path::addArc(const FloatPoint& p, float r, float sar, float ear, bool anticlockwise)
{
qreal xc = p.x();
qreal yc = p.y();
qreal radius = r;
//### HACK
// In Qt we don't switch the coordinate system for degrees
// and still use the 0,0 as bottom left for degrees so we need
// to switch
sar = -sar;
ear = -ear;
anticlockwise = !anticlockwise;
//end hack
float sa = DEGREES(sar);
float ea = DEGREES(ear);
double span = 0;
double xs = xc - radius;
double ys = yc - radius;
double width = radius*2;
double height = radius*2;
if (!anticlockwise && (ea < sa))
span += 360;
else if (anticlockwise && (sa < ea))
span -= 360;
// this is also due to switched coordinate system
// we would end up with a 0 span instead of 360
if (!(qFuzzyCompare(span + (ea - sa) + 1, 1.0) &&
qFuzzyCompare(qAbs(span), 360.0))) {
span += ea - sa;
}
m_path->moveTo(QPointF(xc + radius * cos(sar),
yc - radius * sin(sar)));
m_path->arcTo(xs, ys, width, height, sa, span);
}
void Path::addRect(const FloatRect& r)
{
m_path->addRect(r.x(), r.y(), r.width(), r.height());
}
void Path::addEllipse(const FloatRect& r)
{
m_path->addEllipse(r.x(), r.y(), r.width(), r.height());
}
void Path::clear()
{
*m_path = QPainterPath();
}
bool Path::isEmpty() const
{
// Don't use QPainterPath::isEmpty(), as that also returns true if there's only
// one initial MoveTo element in the path.
return !m_path->elementCount();
}
bool Path::hasCurrentPoint() const
{
return !isEmpty();
}
String Path::debugString() const
{
QString ret;
for (int i = 0; i < m_path->elementCount(); ++i) {
const QPainterPath::Element &cur = m_path->elementAt(i);
switch (cur.type) {
case QPainterPath::MoveToElement:
ret += QString(QLatin1String("M %1 %2")).arg(cur.x).arg(cur.y);
break;
case QPainterPath::LineToElement:
ret += QString(QLatin1String("L %1 %2")).arg(cur.x).arg(cur.y);
break;
case QPainterPath::CurveToElement:
{
const QPainterPath::Element &c1 = m_path->elementAt(i + 1);
const QPainterPath::Element &c2 = m_path->elementAt(i + 2);
Q_ASSERT(c1.type == QPainterPath::CurveToDataElement);
Q_ASSERT(c2.type == QPainterPath::CurveToDataElement);
ret += QString(QLatin1String("C %1 %2 %3 %4 %5 %6")).arg(cur.x).arg(cur.y).arg(c1.x).arg(c1.y).arg(c2.x).arg(c2.y);
i += 2;
break;
}
case QPainterPath::CurveToDataElement:
Q_ASSERT(false);
break;
}
}
return ret;
}
void Path::apply(void* info, PathApplierFunction function) const
{
PathElement pelement;
FloatPoint points[3];
pelement.points = points;
for (int i = 0; i < m_path->elementCount(); ++i) {
const QPainterPath::Element& cur = m_path->elementAt(i);
switch (cur.type) {
case QPainterPath::MoveToElement:
pelement.type = PathElementMoveToPoint;
pelement.points[0] = QPointF(cur);
function(info, &pelement);
break;
case QPainterPath::LineToElement:
pelement.type = PathElementAddLineToPoint;
pelement.points[0] = QPointF(cur);
function(info, &pelement);
break;
case QPainterPath::CurveToElement:
{
const QPainterPath::Element& c1 = m_path->elementAt(i + 1);
const QPainterPath::Element& c2 = m_path->elementAt(i + 2);
Q_ASSERT(c1.type == QPainterPath::CurveToDataElement);
Q_ASSERT(c2.type == QPainterPath::CurveToDataElement);
pelement.type = PathElementAddCurveToPoint;
pelement.points[0] = QPointF(cur);
pelement.points[1] = QPointF(c1);
pelement.points[2] = QPointF(c2);
function(info, &pelement);
i += 2;
break;
}
case QPainterPath::CurveToDataElement:
Q_ASSERT(false);
}
}
}
void Path::transform(const TransformationMatrix& transform)
{
if (m_path) {
QTransform mat = transform;
QPainterPath temp = mat.map(*m_path);
delete m_path;
m_path = new QPainterPath(temp);
}
}
}
// vim: ts=4 sw=4 et