1 /* 2 * Copyright 2010, The Android Open Source Project 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * * Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * * Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #ifndef TiledPage_h 27 #define TiledPage_h 28 29 #if USE(ACCELERATED_COMPOSITING) 30 31 #include "BaseTile.h" 32 #include "SkCanvas.h" 33 #include "SkRegion.h" 34 35 #include "TilePainter.h" 36 37 namespace WebCore { 38 39 class GLWebViewState; 40 class IntRect; 41 42 /** 43 * The TiledPage represents a map of BaseTiles covering the viewport. Each 44 * GLWebViewState contains two TiledPages, one to display the page at the 45 * current scale factor, and another in the background that we use to paint the 46 * page at a different scale factor. For instance, when we zoom using one 47 * TiledPage its tiles are scaled in hardware and therefore are subject to a 48 * loss of quality. To address this when the user finishes zooming we paint the 49 * background TilePage at the new scale factor. When the background TilePage is 50 * ready, we swap it with the currently displaying TiledPage. 51 */ 52 class TiledPage : public TilePainter { 53 public: 54 enum PrepareBounds { 55 ExpandedBounds = 0, 56 VisibleBounds = 1 57 }; 58 59 TiledPage(int id, GLWebViewState* state); 60 ~TiledPage(); 61 62 // returns the other TiledPage who shares the same GLWebViewState 63 TiledPage* sibling(); 64 65 // prepare the page for display on the screen 66 void prepare(bool goingDown, bool goingLeft, const SkIRect& tileBounds, PrepareBounds bounds); 67 68 // update tiles with inval information, return true if visible ones are 69 // dirty (and thus repaint needed) 70 bool updateTileDirtiness(const SkIRect& tileBounds); 71 72 // returns true if the page can't draw the entire region (may still be stale) 73 bool hasMissingContent(const SkIRect& tileBounds); 74 75 bool isReady(const SkIRect& tileBounds); 76 77 // swap 'buffers' by swapping each modified texture 78 bool swapBuffersIfReady(const SkIRect& tileBounds, float scale); 79 // save the transparency and bounds to be drawn in drawGL() 80 void prepareForDrawGL(float transparency, const SkIRect& tileBounds); 81 // draw the page on the screen 82 void drawGL(); 83 84 // TilePainter implementation 85 // used by individual tiles to generate the bitmap for their tile 86 bool paint(BaseTile*, SkCanvas*, unsigned int*); 87 88 // used by individual tiles to get the information about the current picture 89 GLWebViewState* glWebViewState() { return m_glWebViewState; } 90 91 float scale() const { return m_scale; } 92 93 //TODO: clear all textures if this is called with a new value 94 void setScale(float scale) { m_scale = scale; m_invScale = 1 / scale; } 95 96 void invalidateRect(const IntRect& invalRect, const unsigned int pictureCount); 97 void discardTextures(); 98 void updateBaseTileSize(); 99 bool scrollingDown() { return m_scrollingDown; } 100 bool isPrefetchPage() { return m_isPrefetchPage; } 101 void setIsPrefetchPage(bool isPrefetch) { m_isPrefetchPage = isPrefetch; } 102 103 private: 104 void prepareRow(bool goingLeft, int tilesInRow, int firstTileX, int y, const SkIRect& tileBounds); 105 106 BaseTile* getBaseTile(int x, int y) const; 107 108 // array of tiles used to compose a page. The tiles are allocated in the 109 // constructor to prevent them from potentially being allocated on the stack 110 BaseTile* m_baseTiles; 111 // stores the number of tiles in the m_baseTiles array. This enables us to 112 // quickly iterate over the array without have to check it's size 113 int m_baseTileSize; 114 int m_id; 115 float m_scale; 116 float m_invScale; 117 GLWebViewState* m_glWebViewState; 118 119 // used to identify the tiles that have been invalidated (marked dirty) since 120 // the last time updateTileState() has been called. The region is stored in 121 // terms of the (x,y) coordinates used to determine the location of the tile 122 // within the page, not in content/view pixel coordinates. 123 SkRegion m_invalRegion; 124 125 // inval regions in content coordinates 126 SkRegion m_invalTilesRegion; 127 unsigned int m_latestPictureInval; 128 bool m_prepare; 129 bool m_scrollingDown; 130 bool m_isPrefetchPage; 131 132 // info saved in prepare, used in drawGL() 133 bool m_willDraw; 134 SkIRect m_tileBounds; 135 float m_transparency; 136 }; 137 138 } // namespace WebCore 139 140 #endif // USE(ACCELERATED_COMPOSITING) 141 #endif // TiledPage_h 142
