1 /*

     2  * Copyright (C) 2003 Apple Computer, Inc.

     3  *

     4  * Portions are Copyright (C) 1998 Netscape Communications Corporation.

     5  *

     6  * Other contributors:

     7  *   Robert O'Callahan <roc+@cs.cmu.edu>

     8  *   David Baron <dbaron@fas.harvard.edu>

     9  *   Christian Biesinger <cbiesinger@web.de>

    10  *   Randall Jesup <rjesup@wgate.com>

    11  *   Roland Mainz <roland.mainz@informatik.med.uni-giessen.de>

    12  *   Josh Soref <timeless@mac.com>

    13  *   Boris Zbarsky <bzbarsky@mit.edu>

    14  *

    15  * This library is free software; you can redistribute it and/or

    16  * modify it under the terms of the GNU Lesser General Public

    17  * License as published by the Free Software Foundation; either

    18  * version 2.1 of the License, or (at your option) any later version.

    19  *

    20  * This library is distributed in the hope that it will be useful,

    21  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    23  * Lesser General Public License for more details.

    24  *

    25  * You should have received a copy of the GNU Lesser General Public

    26  * License along with this library; if not, write to the Free Software

    27  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

    28  *

    29  * Alternatively, the contents of this file may be used under the terms

    30  * of either the Mozilla Public License Version 1.1, found at

    31  * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public

    32  * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html

    33  * (the "GPL"), in which case the provisions of the MPL or the GPL are

    34  * applicable instead of those above.  If you wish to allow use of your

    35  * version of this file only under the terms of one of those two

    36  * licenses (the MPL or the GPL) and not to allow others to use your

    37  * version of this file under the LGPL, indicate your decision by

    38  * deletingthe provisions above and replace them with the notice and

    39  * other provisions required by the MPL or the GPL, as the case may be.

    40  * If you do not delete the provisions above, a recipient may use your

    41  * version of this file under any of the LGPL, the MPL or the GPL.

    42  */

    43 

    44 #ifndef RenderLayer_h

    45 #define RenderLayer_h

    46 

    47 #include "RenderObject.h"

    48 #include "ScrollBar.h"

    49 #include "Timer.h"

    50 

    51 namespace WebCore {

    52 

    53 class CachedResource;

    54 class HitTestResult;

    55 class PlatformScrollbar;

    56 class RenderFrameSet;

    57 class RenderObject;

    58 class RenderStyle;

    59 class RenderTable;

    60 class RenderText;

    61 class RenderView;

    62 class Scrollbar;

    63 

    64 struct HitTestRequest;

    65 

    66 class ClipRects {

    67 public:

    68     ClipRects(const IntRect& r)

    69         : m_overflowClipRect(r)

    70         , m_fixedClipRect(r)

    71         , m_posClipRect(r)

    72         , m_refCnt(0)

    73         , m_fixed(false)

    74     {

    75     }

    76 

    77     ClipRects(const IntRect& overflowRect, const IntRect& fixedRect, const IntRect& posRect, bool fixed)

    78         : m_overflowClipRect(overflowRect)

    79         , m_fixedClipRect(fixedRect)

    80         , m_posClipRect(posRect)

    81         , m_refCnt(0)

    82         , m_fixed(fixed)

    83     {

    84     }

    85 

    86     const IntRect& overflowClipRect() { return m_overflowClipRect; }

    87     const IntRect& fixedClipRect() { return m_fixedClipRect; }

    88     const IntRect& posClipRect() { return m_posClipRect; }

    89     bool fixed() const { return m_fixed; }

    90 

    91     void ref() { m_refCnt++; }

    92     void deref(RenderArena* renderArena) { if (--m_refCnt == 0) destroy(renderArena); }

    93 

    94     void destroy(RenderArena*);

    95 

    96     // Overloaded new operator.

    97     void* operator new(size_t, RenderArena*) throw();

    98 

    99     // Overridden to prevent the normal delete from being called.

   100     void operator delete(void*, size_t);

   101         

   102 private:

   103     // The normal operator new is disallowed on all render objects.

   104     void* operator new(size_t) throw();

   105 

   106 private:

   107     IntRect m_overflowClipRect;

   108     IntRect m_fixedClipRect;

   109     IntRect m_posClipRect;

   110     unsigned m_refCnt : 31;

   111     bool m_fixed : 1;

   112 };

   113 

   114 

   115 // FIXME: move this to its own file

   116 // This class handles the auto-scrolling of layers with overflow: marquee.

   117 class Marquee {

   118 public:

   119     Marquee(RenderLayer*);

   120 

   121     int speed() const { return m_speed; }

   122     int marqueeSpeed() const;

   123 

   124     EMarqueeDirection reverseDirection() const { return static_cast<EMarqueeDirection>(-direction()); }

   125     EMarqueeDirection direction() const;

   126 

   127     bool isHorizontal() const;

   128 

   129     int computePosition(EMarqueeDirection, bool stopAtClientEdge);

   130 

   131     void setEnd(int end) { m_end = end; }

   132     

   133     void start();

   134     void suspend();

   135     void stop();

   136 

   137     void updateMarqueeStyle();

   138     void updateMarqueePosition();

   139 

   140 private:

   141     void timerFired(Timer<Marquee>*);

   142 

   143     RenderLayer* m_layer;

   144     int m_currentLoop;

   145     int m_totalLoops;

   146     Timer<Marquee> m_timer;

   147     int m_start;

   148     int m_end;

   149     int m_speed;

   150     Length m_height;

   151     bool m_reset: 1;

   152     bool m_suspended : 1;

   153     bool m_stopped : 1;

   154     EMarqueeDirection m_direction : 4;

   155 };

   156 

   157 class RenderLayer : public ScrollbarClient {

   158 public:

   159     enum ScrollBehavior {

   160         noScroll,

   161         alignCenter,

   162         alignTop,

   163         alignBottom, 

   164         alignLeft,

   165         alignRight,

   166         alignToClosestEdge

   167     };

   168 

   169     struct ScrollAlignment {

   170         ScrollBehavior m_rectVisible;

   171         ScrollBehavior m_rectHidden;

   172         ScrollBehavior m_rectPartial;

   173     };

   174 

   175     static const ScrollAlignment gAlignCenterIfNeeded;

   176     static const ScrollAlignment gAlignToEdgeIfNeeded;

   177     static const ScrollAlignment gAlignCenterAlways;

   178     static const ScrollAlignment gAlignTopAlways;

   179     static const ScrollAlignment gAlignBottomAlways;

   180 

   181     static ScrollBehavior getVisibleBehavior(const ScrollAlignment& s) { return s.m_rectVisible; }

   182     static ScrollBehavior getPartialBehavior(const ScrollAlignment& s) { return s.m_rectPartial; }

   183     static ScrollBehavior getHiddenBehavior(const ScrollAlignment& s) { return s.m_rectHidden; }

   184 

   185     RenderLayer(RenderObject*);

   186     ~RenderLayer();

   187 

   188     RenderObject* renderer() const { return m_object; }

   189     RenderLayer* parent() const { return m_parent; }

   190     RenderLayer* previousSibling() const { return m_previous; }

   191     RenderLayer* nextSibling() const { return m_next; }

   192     RenderLayer* firstChild() const { return m_first; }

   193     RenderLayer* lastChild() const { return m_last; }

   194 

   195     void addChild(RenderLayer* newChild, RenderLayer* beforeChild = 0);

   196     RenderLayer* removeChild(RenderLayer*);

   197 

   198     void removeOnlyThisLayer();

   199     void insertOnlyThisLayer();

   200 

   201     void repaintIncludingDescendants();

   202 

   203     void styleChanged();

   204 

   205     Marquee* marquee() const { return m_marquee; }

   206     void suspendMarquees();

   207 

   208     bool isOverflowOnly() const { return m_isOverflowOnly; }

   209 

   210     bool isTransparent() const;

   211     RenderLayer* transparentAncestor();

   212     void beginTransparencyLayers(GraphicsContext*, const IntRect&);

   213 

   214     const RenderLayer* root() const

   215     {

   216         const RenderLayer* curr = this;

   217         while (curr->parent())

   218             curr = curr->parent();

   219         return curr;

   220     }

   221     

   222     int xPos() const { return m_x; }

   223     int yPos() const { return m_y; }

   224     void setPos(int xPos, int yPos)

   225     {

   226         m_x = xPos;

   227         m_y = yPos;

   228     }

   229 

   230     int width() const { return m_width; }

   231     int height() const { return m_height; }

   232     void setWidth(int w) { m_width = w; }

   233     void setHeight(int h) { m_height = h; }

   234 

   235     int scrollWidth();

   236     int scrollHeight();

   237 

   238     // Scrolling methods for layers that can scroll their overflow.

   239     void scrollOffset(int& x, int& y);

   240     void subtractScrollOffset(int& x, int& y);

   241     int scrollXOffset() const { return m_scrollX + m_scrollOriginX; }

   242     int scrollYOffset() const { return m_scrollY; }

   243     void scrollToOffset(int x, int y, bool updateScrollbars = true, bool repaint = true);

   244     void scrollToXOffset(int x) { scrollToOffset(x, m_scrollY); }

   245     void scrollToYOffset(int y) { scrollToOffset(m_scrollX + m_scrollOriginX, y); }

   246     void scrollRectToVisible(const IntRect&, const ScrollAlignment& alignX = gAlignCenterIfNeeded, const ScrollAlignment& alignY = gAlignCenterIfNeeded);

   247 

   248     IntRect getRectToExpose(const IntRect& visibleRect, const IntRect& exposeRect, const ScrollAlignment& alignX, const ScrollAlignment& alignY);    

   249 

   250     void setHasHorizontalScrollbar(bool);

   251     void setHasVerticalScrollbar(bool);

   252 

   253     PassRefPtr<Scrollbar> createScrollbar(ScrollbarOrientation);

   254     void destroyScrollbar(ScrollbarOrientation);

   255 

   256     Scrollbar* horizontalScrollbar() { return m_hBar.get(); }

   257     Scrollbar* verticalScrollbar() { return m_vBar.get(); }

   258 

   259     PlatformScrollbar* horizontalScrollbarWidget() const;

   260     PlatformScrollbar* verticalScrollbarWidget() const;

   261 

   262     int verticalScrollbarWidth() const;

   263     int horizontalScrollbarHeight() const;

   264 

   265     void positionOverflowControls();

   266     bool isPointInResizeControl(const IntPoint&);

   267     bool hitTestOverflowControls(HitTestResult&);

   268     IntSize offsetFromResizeCorner(const IntPoint&) const;

   269 

   270     void paintOverflowControls(GraphicsContext*, int tx, int ty, const IntRect& damageRect);

   271 

   272     void updateScrollInfoAfterLayout();

   273 

   274     bool scroll(ScrollDirection, ScrollGranularity, float multiplier = 1.0f);

   275     void autoscroll();

   276 

   277     void resize(const PlatformMouseEvent&, const IntSize&);

   278     bool inResizeMode() const { return m_inResizeMode; }

   279     void setInResizeMode(bool b) { m_inResizeMode = b; }

   280     

   281     void updateLayerPosition();

   282     void updateLayerPositions(bool doFullRepaint = false, bool checkForRepaint = true);

   283 

   284     void relativePositionOffset(int& relX, int& relY) { relX += m_relX; relY += m_relY; }

   285 

   286     void clearClipRects();

   287     void clearClipRect();

   288 

   289     // Get the enclosing stacking context for this layer.  A stacking context is a layer

   290     // that has a non-auto z-index.

   291     RenderLayer* stackingContext() const;

   292     bool isStackingContext() const { return !hasAutoZIndex() || renderer()->isRenderView(); }

   293 

   294     void dirtyZOrderLists();

   295     void updateZOrderLists();

   296     Vector<RenderLayer*>* posZOrderList() const { return m_posZOrderList; }

   297     Vector<RenderLayer*>* negZOrderList() const { return m_negZOrderList; }

   298 

   299     void dirtyOverflowList();

   300     void updateOverflowList();

   301     Vector<RenderLayer*>* overflowList() const { return m_overflowList; }

   302 

   303     bool hasVisibleContent() const { return m_hasVisibleContent; }

   304     void setHasVisibleContent(bool);

   305     void dirtyVisibleContentStatus();

   306 

   307     // Gets the nearest enclosing positioned ancestor layer (also includes

   308     // the <html> layer and the root layer).

   309     RenderLayer* enclosingPositionedAncestor() const;

   310 

   311     void convertToLayerCoords(const RenderLayer* ancestorLayer, int& x, int& y) const;

   312 

   313     bool hasAutoZIndex() const { return renderer()->style()->hasAutoZIndex(); }

   314     int zIndex() const { return renderer()->style()->zIndex(); }

   315 

   316     // The two main functions that use the layer system.  The paint method

   317     // paints the layers that intersect the damage rect from back to

   318     // front.  The hitTest method looks for mouse events by walking

   319     // layers that intersect the point from front to back.

   320     void paint(GraphicsContext*, const IntRect& damageRect, PaintRestriction = PaintRestrictionNone, RenderObject* paintingRoot = 0);

   321     bool hitTest(const HitTestRequest&, HitTestResult&);

   322 

   323     // This method figures out our layerBounds in coordinates relative to

   324     // |rootLayer}.  It also computes our background and foreground clip rects

   325     // for painting/event handling.

   326     void calculateRects(const RenderLayer* rootLayer, const IntRect& paintDirtyRect, IntRect& layerBounds,

   327                         IntRect& backgroundRect, IntRect& foregroundRect, IntRect& outlineRect) const;

   328     void calculateClipRects(const RenderLayer* rootLayer);

   329     ClipRects* clipRects() const { return m_clipRects; }

   330     IntRect childrenClipRect() const; // Returns the foreground clip rect of the layer in the document's coordinate space.

   331     IntRect selfClipRect() const; // Returns the background clip rect of the layer in the document's coordinate space.

   332 

   333     bool intersectsDamageRect(const IntRect& layerBounds, const IntRect& damageRect) const;

   334 

   335     // Returns a bounding box for this layer only.

   336     IntRect absoluteBoundingBox() const;

   337 

   338     void updateHoverActiveState(const HitTestRequest&, HitTestResult&);

   339 

   340     IntRect repaintRect() const { return m_repaintRect; }

   341     void setNeedsFullRepaint(bool f = true) { m_needsFullRepaint = f; }

   342     

   343     int staticX() const { return m_staticX; }

   344     int staticY() const { return m_staticY; }

   345     void setStaticX(int staticX) { m_staticX = staticX; }

   346     void setStaticY(int staticY) { m_staticY = staticY; }

   347 

   348     void destroy(RenderArena*);

   349 

   350      // Overloaded new operator.  Derived classes must override operator new

   351     // in order to allocate out of the RenderArena.

   352     void* operator new(size_t, RenderArena*) throw();

   353 

   354     // Overridden to prevent the normal delete from being called.

   355     void operator delete(void*, size_t);

   356 

   357 private:

   358     // The normal operator new is disallowed on all render objects.

   359     void* operator new(size_t) throw();

   360 

   361 private:

   362     void setNextSibling(RenderLayer* next) { m_next = next; }

   363     void setPreviousSibling(RenderLayer* prev) { m_previous = prev; }

   364     void setParent(RenderLayer* parent) { m_parent = parent; }

   365     void setFirstChild(RenderLayer* first) { m_first = first; }

   366     void setLastChild(RenderLayer* last) { m_last = last; }

   367 

   368     void collectLayers(Vector<RenderLayer*>*&, Vector<RenderLayer*>*&);

   369 

   370     void paintLayer(RenderLayer* rootLayer, GraphicsContext*, const IntRect& paintDirtyRect,

   371                     bool haveTransparency, PaintRestriction, RenderObject* paintingRoot);

   372     RenderLayer* hitTestLayer(RenderLayer* rootLayer, const HitTestRequest&, HitTestResult&, const IntRect& hitTestRect);

   373     void computeScrollDimensions(bool* needHBar = 0, bool* needVBar = 0);

   374 

   375     bool shouldBeOverflowOnly() const;

   376 

   377     virtual void valueChanged(Scrollbar*);

   378     virtual IntRect windowClipRect() const;

   379 

   380     void updateOverflowStatus(bool horizontalOverflow, bool verticalOverflow);

   381 

   382     void childVisibilityChanged(bool newVisibility);

   383     void dirtyVisibleDescendantStatus();

   384     void updateVisibilityStatus();

   385 

   386     Node* enclosingElement() const;

   387 

   388 protected:   

   389     RenderObject* m_object;

   390 

   391     RenderLayer* m_parent;

   392     RenderLayer* m_previous;

   393     RenderLayer* m_next;

   394     RenderLayer* m_first;

   395     RenderLayer* m_last;

   396 

   397     IntRect m_repaintRect; // Cached repaint rects. Used by layout.

   398     IntRect m_outlineBox;

   399 

   400     // Our current relative position offset.

   401     int m_relX;

   402     int m_relY;

   403 

   404     // Our (x,y) coordinates are in our parent layer's coordinate space.

   405     int m_x;

   406     int m_y;

   407 

   408     // The layer's width/height

   409     int m_width;

   410     int m_height;

   411 

   412     // Our scroll offsets if the view is scrolled.

   413     int m_scrollX;

   414     int m_scrollY;

   415     int m_scrollOriginX;

   416     int m_scrollLeftOverflow;

   417 

   418     // The width/height of our scrolled area.

   419     int m_scrollWidth;

   420     int m_scrollHeight;

   421 

   422     // For layers with overflow, we have a pair of scrollbars.

   423     RefPtr<Scrollbar> m_hBar;

   424     RefPtr<Scrollbar> m_vBar;

   425 

   426     // Keeps track of whether the layer is currently resizing, so events can cause resizing to start and stop.

   427     bool m_inResizeMode;

   428 

   429     // For layers that establish stacking contexts, m_posZOrderList holds a sorted list of all the

   430     // descendant layers within the stacking context that have z-indices of 0 or greater

   431     // (auto will count as 0).  m_negZOrderList holds descendants within our stacking context with negative

   432     // z-indices.

   433     Vector<RenderLayer*>* m_posZOrderList;

   434     Vector<RenderLayer*>* m_negZOrderList;

   435 

   436     // This list contains our overflow child layers.

   437     Vector<RenderLayer*>* m_overflowList;

   438 

   439     ClipRects* m_clipRects;      // Cached clip rects used when painting and hit testing.

   440 

   441     bool m_scrollDimensionsDirty : 1;

   442     bool m_zOrderListsDirty : 1;

   443     bool m_overflowListDirty: 1;

   444     bool m_isOverflowOnly: 1;

   445 

   446     bool m_usedTransparency : 1; // Tracks whether we need to close a transparent layer, i.e., whether

   447                                  // we ended up painting this layer or any descendants (and therefore need to

   448                                  // blend).

   449     bool m_inOverflowRelayout : 1;

   450     bool m_needsFullRepaint : 1;

   451 

   452     bool m_overflowStatusDirty : 1;

   453     bool m_horizontalOverflow : 1;

   454     bool m_verticalOverflow : 1;

   455     bool m_visibleContentStatusDirty : 1;

   456     bool m_hasVisibleContent : 1;

   457     bool m_visibleDescendantStatusDirty : 1;

   458     bool m_hasVisibleDescendant : 1;

   459 

   460     Marquee* m_marquee; // Used by layers with overflow:marquee

   461     

   462     // Cached normal flow values for absolute positioned elements with static left/top values.

   463     int m_staticX;

   464     int m_staticY;

   465 };

   466 

   467 } // namespace WebCore

   468 

   469 #endif // RenderLayer_h