layout/svg/base/src/nsSVGGradientFrame.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is the Mozilla SVG project.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Scooter Morris.
  19  * Portions created by the Initial Developer are Copyright (C) 2004
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Scooter Morris <scootermorris@comcast.net>
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either the GNU General Public License Version 2 or later (the "GPL"), or
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  34  * the provisions above, a recipient may use your version of this file under
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  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #ifndef __NS_SVGGRADIENTFRAME_H__
  40 #define __NS_SVGGRADIENTFRAME_H__
  41
  42 #include "nsSVGPaintServerFrame.h"
  43 #include "nsISVGValueObserver.h"
  44 #include "nsWeakReference.h"
  45 #include "nsSVGElement.h"
  46 #include "gfxPattern.h"
  47
  48 class nsIDOMSVGStopElement;
  49
  50 typedef nsSVGPaintServerFrame nsSVGGradientFrameBase;
  51
  52 /**
  53  * Gradients can refer to other gradients. We create an nsSVGPaintingProperty
  54  * with property type nsGkAtoms::href to track the referenced gradient.
  55  */
  56 class nsSVGGradientFrame : public nsSVGGradientFrameBase
  57 {
  58 protected:
  59   nsSVGGradientFrame(nsStyleContext* aContext);
  60
  61 public:
  62   // nsSVGPaintServerFrame methods:
  63   virtual PRBool SetupPaintServer(gfxContext *aContext,
  64                                   nsSVGGeometryFrame *aSource,
  65                                   float aGraphicOpacity);
  66
  67   // nsIFrame interface:
  68   virtual void DidSetStyleContext(nsStyleContext* aOldStyleContext);
  69
  70   NS_IMETHOD AttributeChanged(PRInt32         aNameSpaceID,
  71                               nsIAtom*        aAttribute,
  72                               PRInt32         aModType);
  73
  74 #ifdef DEBUG
  75   // nsIFrameDebug interface:
  76   NS_IMETHOD GetFrameName(nsAString& aResult) const
  77   {
  78     return MakeFrameName(NS_LITERAL_STRING("SVGGradient"), aResult);
  79   }
  80 #endif // DEBUG
  81
  82 private:
  83
  84   // Parse our xlink:href and set up our nsSVGPaintingProperty if we
  85   // reference another gradient and we don't have a property. Return
  86   // the referenced gradient's frame if available, null otherwise.
  87   nsSVGGradientFrame* GetReferencedGradient();
  88
  89   // Helpers to look at our gradient and then along its reference chain (if any)
  90   // to find the first gradient with the specified attribute.
  91   // Returns aDefault if no content with that attribute is found
  92   nsSVGGradientElement* GetGradientWithAttr(nsIAtom *aAttrName, nsIContent *aDefault);
  93
  94   // Some attributes are only valid on one type of gradient, and we *must* get
  95   // the right type or we won't have the data structures we require.
  96   // Returns aDefault if no content with that attribute is found
  97   nsSVGGradientElement* GetGradientWithAttr(nsIAtom *aAttrName, nsIAtom *aGradType,
  98                                             nsIContent *aDefault);
  99
 100   // Optionally get a stop frame (returns stop index/count)
 101   PRInt32 GetStopFrame(PRInt32 aIndex, nsIFrame * *aStopFrame);
 102
 103   PRUint16 GetSpreadMethod();
 104   PRUint32 GetStopCount();
 105   void GetStopInformation(PRInt32 aIndex,
 106                           float *aOffset, nscolor *aColor, float *aStopOpacity);
 107   gfxMatrix GetGradientTransform(nsSVGGeometryFrame *aSource);
 108
 109 protected:
 110   virtual already_AddRefed<gfxPattern> CreateGradient() = 0;
 111
 112   // Use these inline methods instead of GetGradientWithAttr(..., aGradType)
 113   nsSVGLinearGradientElement* GetLinearGradientWithAttr(nsIAtom *aAttrName, nsIContent *aDefault)
 114   {
 115     return static_cast<nsSVGLinearGradientElement*>(
 116             GetGradientWithAttr(aAttrName, nsGkAtoms::svgLinearGradientFrame, aDefault));
 117   }
 118   nsSVGRadialGradientElement* GetRadialGradientWithAttr(nsIAtom *aAttrName, nsIContent *aDefault)
 119   {
 120     return static_cast<nsSVGRadialGradientElement*>(
 121             GetGradientWithAttr(aAttrName, nsGkAtoms::svgRadialGradientFrame, aDefault));
 122   }
 123
 124   // Get the value of our gradientUnits attribute
 125   PRUint16 GetGradientUnits();
 126
 127   // The graphic element our gradient is (currently) being applied to
 128   nsRefPtr<nsSVGElement>                 mSourceContent;
 129
 130 private:
 131   // Flag to mark this frame as "in use" during recursive calls along our
 132   // gradient's reference chain so we can detect reference loops. See:
 133   // http://www.w3.org/TR/SVG11/pservers.html#LinearGradientElementHrefAttribute
 134   PRPackedBool                           mLoopFlag;
 135   // Gradients often don't reference other gradients, so here we cache
 136   // the fact that that isn't happening.
 137   PRPackedBool                           mNoHRefURI;
 138 };
 139
 140
 141 // -------------------------------------------------------------------------
 142 // Linear Gradients
 143 // -------------------------------------------------------------------------
 144
 145 typedef nsSVGGradientFrame nsSVGLinearGradientFrameBase;
 146
 147 class nsSVGLinearGradientFrame : public nsSVGLinearGradientFrameBase
 148 {
 149   friend nsIFrame* NS_NewSVGLinearGradientFrame(nsIPresShell* aPresShell,
 150                                                 nsIContent*   aContent,
 151                                                 nsStyleContext* aContext);
 152 protected:
 153   nsSVGLinearGradientFrame(nsStyleContext* aContext) :
 154     nsSVGLinearGradientFrameBase(aContext) {}
 155
 156 public:
 157   // nsIFrame interface:
 158   virtual nsIAtom* GetType() const;  // frame type: nsGkAtoms::svgLinearGradientFrame
 159
 160   NS_IMETHOD AttributeChanged(PRInt32         aNameSpaceID,
 161                               nsIAtom*        aAttribute,
 162                               PRInt32         aModType);
 163
 164 #ifdef DEBUG
 165   // nsIFrameDebug interface:
 166   NS_IMETHOD GetFrameName(nsAString& aResult) const
 167   {
 168     return MakeFrameName(NS_LITERAL_STRING("SVGLinearGradient"), aResult);
 169   }
 170 #endif // DEBUG
 171
 172 protected:
 173   float GradientLookupAttribute(nsIAtom *aAtomName, PRUint16 aEnumName);
 174   virtual already_AddRefed<gfxPattern> CreateGradient();
 175 };
 176
 177 // -------------------------------------------------------------------------
 178 // Radial Gradients
 179 // -------------------------------------------------------------------------
 180
 181 typedef nsSVGGradientFrame nsSVGRadialGradientFrameBase;
 182
 183 class nsSVGRadialGradientFrame : public nsSVGRadialGradientFrameBase
 184 {
 185   friend nsIFrame* NS_NewSVGRadialGradientFrame(nsIPresShell* aPresShell,
 186                                                 nsIContent*   aContent,
 187                                                 nsStyleContext* aContext);
 188 protected:
 189   nsSVGRadialGradientFrame(nsStyleContext* aContext) :
 190     nsSVGRadialGradientFrameBase(aContext) {}
 191
 192 public:
 193   // nsIFrame interface:
 194   virtual nsIAtom* GetType() const;  // frame type: nsGkAtoms::svgRadialGradientFrame
 195
 196   NS_IMETHOD AttributeChanged(PRInt32         aNameSpaceID,
 197                               nsIAtom*        aAttribute,
 198                               PRInt32         aModType);
 199
 200 #ifdef DEBUG
 201   // nsIFrameDebug interface:
 202   NS_IMETHOD GetFrameName(nsAString& aResult) const
 203   {
 204     return MakeFrameName(NS_LITERAL_STRING("SVGRadialGradient"), aResult);
 205   }
 206 #endif // DEBUG
 207
 208 protected:
 209   float GradientLookupAttribute(nsIAtom *aAtomName, PRUint16 aEnumName,
 210                                 nsSVGRadialGradientElement *aElement = nsnull);
 211   virtual already_AddRefed<gfxPattern> CreateGradient();
 212 };
 213
 214 #endif // __NS_SVGGRADIENTFRAME_H__
 215