/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (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.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is the Mozilla SVG project. * * The Initial Developer of the Original Code is * Crocodile Clips Ltd.. * Portions created by the Initial Developer are Copyright (C) 2002 * the Initial Developer. All Rights Reserved. * * Contributor(s): * Alex Fritze (original author) * * Alternatively, the contents of this file may be used under the terms of * either of the GNU General Public License Version 2 or later (the "GPL"), * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ #include // unknwn.h is needed to build with WIN32_LEAN_AND_MEAN #include #include using namespace Gdiplus; #include "nsCOMPtr.h" #include "nsISVGPathGeometrySource.h" #include "nsISVGRendererPathBuilder.h" #include /** * \addtogroup gdiplus_renderer GDI+ Rendering Engine * @{ */ //////////////////////////////////////////////////////////////////////// /** * Helper class used by nsSVGGDIPlusPathBuilder * * Maintains a stack of points during the path building process. */ class PointStack { public: PointStack(); ~PointStack(); struct PointData { float x; float y; }; void PushPoint(float x, float y); const PointData *PopPoint(); private: void Grow(); PointData mOrigin; PointData *mPoints; int mCapacity; int mSize; }; /** @} */ PointStack::PointStack() : mPoints(0), mCapacity(0), mSize(0) { mOrigin.x = 0.0f; mOrigin.y = 0.0f; } PointStack::~PointStack() { if (mPoints) delete[] mPoints; } void PointStack::PushPoint(float x, float y) { if (mCapacity-mSize<1) Grow(); NS_ASSERTION(mCapacity-mSize>0, "no space in array"); mPoints[mSize].x = x; mPoints[mSize].y = y; ++mSize; } const PointStack::PointData *PointStack::PopPoint() { if (mSize == 0) return &mOrigin; return &mPoints[--mSize]; } void PointStack::Grow() { // nested subpaths are not very common, so we'll just grow linearly PointData *oldPoints = mPoints; mPoints = new PointData[++mCapacity]; if (oldPoints) { memcpy(mPoints, oldPoints, sizeof(PointData) * mSize); delete[] oldPoints; } } /** * \addtogroup gdiplus_renderer GDI+ Rendering Engine * @{ */ //////////////////////////////////////////////////////////////////////// /** * GDI+ path builder implementation */ class nsSVGGDIPlusPathBuilder : public nsISVGRendererPathBuilder { protected: friend nsresult NS_NewSVGGDIPlusPathBuilder(nsISVGRendererPathBuilder **result, nsISVGPathGeometrySource *src, GraphicsPath* dest); nsSVGGDIPlusPathBuilder(nsISVGPathGeometrySource *src, GraphicsPath* dest); public: // nsISupports interface: NS_DECL_ISUPPORTS // nsISVGRendererPathBuilder interface: NS_DECL_NSISVGRENDERERPATHBUILDER private: nsCOMPtr mSource; GraphicsPath *mPath; PointStack mSubPathStack; PointF mCurrentPoint; }; /** @} */ //---------------------------------------------------------------------- // implementation: nsSVGGDIPlusPathBuilder::nsSVGGDIPlusPathBuilder(nsISVGPathGeometrySource *src, GraphicsPath* dest) : mSource(src), mPath(dest) { PRUint16 fillrule; mSource->GetFillRule(&fillrule); mPath->SetFillMode(fillrule==nsISVGGeometrySource::FILL_RULE_NONZERO ? FillModeWinding : FillModeAlternate); } nsresult NS_NewSVGGDIPlusPathBuilder(nsISVGRendererPathBuilder **result, nsISVGPathGeometrySource *src, GraphicsPath* dest) { *result = new nsSVGGDIPlusPathBuilder(src, dest); if (!result) return NS_ERROR_OUT_OF_MEMORY; NS_ADDREF(*result); return NS_OK; } //---------------------------------------------------------------------- // nsISupports methods: NS_IMPL_ADDREF(nsSVGGDIPlusPathBuilder) NS_IMPL_RELEASE(nsSVGGDIPlusPathBuilder) NS_INTERFACE_MAP_BEGIN(nsSVGGDIPlusPathBuilder) NS_INTERFACE_MAP_ENTRY(nsISVGRendererPathBuilder) NS_INTERFACE_MAP_ENTRY(nsISupports) NS_INTERFACE_MAP_END //---------------------------------------------------------------------- // nsISVGRendererPathBuilder methods: /** Implements void moveto(in float x, in float y); */ NS_IMETHODIMP nsSVGGDIPlusPathBuilder::Moveto(float x, float y) { // mPath->CloseFigure(); mPath->StartFigure(); mCurrentPoint.X = x; mCurrentPoint.Y = y; mSubPathStack.PushPoint(x, y); return NS_OK; } /** Implements void lineto(in float x, in float y); */ NS_IMETHODIMP nsSVGGDIPlusPathBuilder::Lineto(float x, float y) { mPath->AddLine(mCurrentPoint.X, mCurrentPoint.Y, x, y); mCurrentPoint.X = x; mCurrentPoint.Y = y; return NS_OK; } /** Implements void curveto(in float x, in float y, in float x1, in float y1, in float x2, in float y2); */ NS_IMETHODIMP nsSVGGDIPlusPathBuilder::Curveto(float x, float y, float x1, float y1, float x2, float y2) { mPath->AddBezier(mCurrentPoint.X, mCurrentPoint.Y, // startpoint x1, y1, x2, y2, // controlpoints x, y); // endpoint mCurrentPoint.X = x; mCurrentPoint.Y = y; return NS_OK; } /* helper for Arcto : */ static inline double CalcVectorAngle(double ux, double uy, double vx, double vy) { double ta = atan2(uy, ux); double tb = atan2(vy, vx); if (tb >= ta) return tb-ta; return 6.28318530718 - (ta-tb); } /** Implements void arcto(in float x, in float y, in float r1, in float r2, in float angle, in boolean largeArcFlag, in boolean sweepFlag); */ NS_IMETHODIMP nsSVGGDIPlusPathBuilder::Arcto(float x2, float y2, float rx, float ry, float angle, PRBool largeArcFlag, PRBool sweepFlag) { const double pi = 3.14159265359; const double radPerDeg = pi/180.0; float x1=mCurrentPoint.X, y1=mCurrentPoint.Y; // 1. Treat out-of-range parameters as described in // http://www.w3.org/TR/SVG/implnote.html#ArcImplementationNotes // If the endpoints (x1, y1) and (x2, y2) are identical, then this // is equivalent to omitting the elliptical arc segment entirely if (x1 == x2 && y1 == y2) return NS_OK; // If rX = 0 or rY = 0 then this arc is treated as a straight line // segment (a "lineto") joining the endpoints. if (rx == 0.0f || ry == 0.0f) { return Lineto(x2, y2); } // If rX or rY have negative signs, these are dropped; the absolute // value is used instead. if (rx<0.0) rx = -rx; if (ry<0.0) ry = -ry; // 2. convert to center parameterization as shown in // http://www.w3.org/TR/SVG/implnote.html double sinPhi = sin(angle*radPerDeg); double cosPhi = cos(angle*radPerDeg); double x1dash = cosPhi * (x1-x2)/2.0 + sinPhi * (y1-y2)/2.0; double y1dash = -sinPhi * (x1-x2)/2.0 + cosPhi * (y1-y2)/2.0; double root; double numerator = rx*rx*ry*ry - rx*rx*y1dash*y1dash - ry*ry*x1dash*x1dash; if (numerator < 0.0) { // If rX , rY and are such that there is no solution (basically, // the ellipse is not big enough to reach from (x1, y1) to (x2, // y2)) then the ellipse is scaled up uniformly until there is // exactly one solution (until the ellipse is just big enough). // -> find factor s, such that numerator' with rx'=s*rx and // ry'=s*ry becomes 0 : float s = (float)sqrt(1.0 - numerator/(rx*rx*ry*ry)); rx *= s; ry *= s; root = 0.0; } else { root = (largeArcFlag == sweepFlag ? -1.0 : 1.0) * sqrt( numerator/(rx*rx*y1dash*y1dash+ry*ry*x1dash*x1dash) ); } double cxdash = root*rx*y1dash/ry; double cydash = -root*ry*x1dash/rx; double cx = cosPhi * cxdash - sinPhi * cydash + (x1+x2)/2.0; double cy = sinPhi * cxdash + cosPhi * cydash + (y1+y2)/2.0; double theta1 = CalcVectorAngle(1.0, 0.0, (x1dash-cxdash)/rx, (y1dash-cydash)/ry); double dtheta = CalcVectorAngle((x1dash-cxdash)/rx, (y1dash-cydash)/ry, (-x1dash-cxdash)/rx, (-y1dash-cydash)/ry); if (!sweepFlag && dtheta>0) dtheta -= 2.0*pi; else if (sweepFlag && dtheta<0) dtheta += 2.0*pi; // 3. convert into cubic bezier segments <= 90deg int segments = (int)ceil(fabs(dtheta/(pi/2.0))); double delta = dtheta/segments; double t = 8.0/3.0 * sin(delta/4.0) * sin(delta/4.0) / sin(delta/2.0); for (int i = 0; i < segments; ++i) { double cosTheta1 = cos(theta1); double sinTheta1 = sin(theta1); double theta2 = theta1 + delta; double cosTheta2 = cos(theta2); double sinTheta2 = sin(theta2); // a) calculate endpoint of the segment: double xe = cosPhi * rx*cosTheta2 - sinPhi * ry*sinTheta2 + cx; double ye = sinPhi * rx*cosTheta2 + cosPhi * ry*sinTheta2 + cy; // b) calculate gradients at start/end points of segment: double dx1 = t * ( - cosPhi * rx*sinTheta1 - sinPhi * ry*cosTheta1); double dy1 = t * ( - sinPhi * rx*sinTheta1 + cosPhi * ry*cosTheta1); double dxe = t * ( cosPhi * rx*sinTheta2 + sinPhi * ry*cosTheta2); double dye = t * ( sinPhi * rx*sinTheta2 - cosPhi * ry*cosTheta2); // c) draw the cubic bezier: Curveto((float)xe, (float)ye, (float)(x1+dx1), (float)(y1+dy1), (float)(xe+dxe), (float)(ye+dye)); // do next segment theta1 = theta2; x1 = (float)xe; y1 = (float)ye; } return NS_OK; } /** Implements void closePath(out float newX, out float newY); */ NS_IMETHODIMP nsSVGGDIPlusPathBuilder::ClosePath(float *newX, float *newY) { mPath->CloseFigure(); const PointStack::PointData *point = mSubPathStack.PopPoint(); *newX = point->x; *newY = point->y; mCurrentPoint.X = point->x; mCurrentPoint.Y = point->y; return NS_OK; } /** Implements void endPath(); */ NS_IMETHODIMP nsSVGGDIPlusPathBuilder::EndPath() { return NS_OK; }