1 /* 2 * Copyright (C) 2008 Apple Inc. All rights reserved. 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 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. 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 APPLE COMPUTER, INC. ``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 APPLE COMPUTER, INC. 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 #include "config.h" 27 #include "GraphicsContext.h" 28 29 #include "AffineTransform.h" 30 #include "Path.h" 31 32 #include <cairo-win32.h> 33 #include "GraphicsContextPlatformPrivateCairo.h" 34 35 using namespace std; 36 37 namespace WebCore { 38 39 static cairo_t* createCairoContextWithHDC(HDC hdc, bool hasAlpha) 40 { 41 // Put the HDC In advanced mode so it will honor affine transforms. 42 SetGraphicsMode(hdc, GM_ADVANCED); 43 44 cairo_surface_t* surface = 0; 45 46 HBITMAP bitmap = static_cast<HBITMAP>(GetCurrentObject(hdc, OBJ_BITMAP)); 47 48 BITMAP info; 49 if (!GetObject(bitmap, sizeof(info), &info)) 50 surface = cairo_win32_surface_create(hdc); 51 else { 52 ASSERT(info.bmBitsPixel == 32); 53 54 surface = cairo_image_surface_create_for_data((unsigned char*)info.bmBits, 55 CAIRO_FORMAT_ARGB32, 56 info.bmWidth, 57 info.bmHeight, 58 info.bmWidthBytes); 59 } 60 61 cairo_t* context = cairo_create(surface); 62 cairo_surface_destroy(surface); 63 64 return context; 65 } 66 67 GraphicsContext::GraphicsContext(HDC dc, bool hasAlpha) 68 : m_updatingControlTints(false) 69 { 70 platformInit(dc, hasAlpha); 71 } 72 73 void GraphicsContext::platformInit(HDC dc, bool hasAlpha) 74 { 75 cairo_t* cr = 0; 76 if (dc) 77 cr = createCairoContextWithHDC(dc, hasAlpha); 78 else 79 setPaintingDisabled(true); 80 81 m_data = new GraphicsContextPlatformPrivateToplevel(new PlatformContextCairo(cr)); 82 m_data->m_hdc = dc; 83 if (platformContext()->cr()) { 84 // Make sure the context starts in sync with our state. 85 setPlatformFillColor(fillColor(), fillColorSpace()); 86 setPlatformStrokeColor(strokeColor(), strokeColorSpace()); 87 } 88 } 89 90 static void setRGBABitmapAlpha(unsigned char* bytes, size_t length, unsigned char level) 91 { 92 for (size_t i = 0; i < length; i += 4) 93 bytes[i + 3] = level; 94 } 95 96 static void drawBitmapToContext(GraphicsContextPlatformPrivate* context, cairo_t* cr, const DIBPixelData& pixelData, const IntSize& translate) 97 { 98 // Need to make a cairo_surface_t out of the bitmap's pixel buffer and then draw 99 // it into our context. 100 cairo_surface_t* surface = cairo_image_surface_create_for_data(pixelData.buffer(), 101 CAIRO_FORMAT_ARGB32, 102 pixelData.size().width(), 103 pixelData.size().height(), 104 pixelData.bytesPerRow()); 105 106 // Flip the target surface so that when we set the srcImage as 107 // the surface it will draw right-side-up. 108 cairo_save(cr); 109 cairo_translate(cr, static_cast<double>(translate.width()), static_cast<double>(translate.height())); 110 cairo_scale(cr, 1, -1); 111 cairo_set_source_surface(cr, surface, 0, 0); 112 113 if (context->layers.size()) 114 cairo_paint_with_alpha(cr, context->layers.last()); 115 else 116 cairo_paint(cr); 117 118 // Delete all our junk. 119 cairo_surface_destroy(surface); 120 cairo_restore(cr); 121 } 122 123 void GraphicsContext::releaseWindowsContext(HDC hdc, const IntRect& dstRect, bool supportAlphaBlend, bool mayCreateBitmap) 124 { 125 bool createdBitmap = mayCreateBitmap && (!m_data->m_hdc || inTransparencyLayer()); 126 if (!hdc || !createdBitmap) { 127 m_data->restore(); 128 return; 129 } 130 131 if (dstRect.isEmpty()) 132 return; 133 134 OwnPtr<HBITMAP> bitmap = adoptPtr(static_cast<HBITMAP>(GetCurrentObject(hdc, OBJ_BITMAP))); 135 136 DIBPixelData pixelData(bitmap.get()); 137 ASSERT(pixelData.bitsPerPixel() == 32); 138 139 // If this context does not support alpha blending, then it may have 140 // been drawn with GDI functions which always set the alpha channel 141 // to zero. We need to manually set the bitmap to be fully opaque. 142 unsigned char* bytes = reinterpret_cast<unsigned char*>(pixelData.buffer()); 143 if (!supportAlphaBlend) 144 setRGBABitmapAlpha(bytes, pixelData.size().height() * pixelData.bytesPerRow(), 255); 145 146 drawBitmapToContext(m_data, platformContext()->cr(), pixelData, IntSize(dstRect.x(), dstRect.height() + dstRect.y())); 147 148 ::DeleteDC(hdc); 149 } 150 151 void GraphicsContext::drawWindowsBitmap(WindowsBitmap* bitmap, const IntPoint& point) 152 { 153 drawBitmapToContext(m_data, platformContext()->cr(), bitmap->windowsDIB(), IntSize(point.x(), bitmap->size().height() + point.y())); 154 } 155 156 void GraphicsContextPlatformPrivate::syncContext(cairo_t* cr) 157 { 158 if (!cr) 159 return; 160 161 cairo_surface_t* surface = cairo_get_target(cr); 162 m_hdc = cairo_win32_surface_get_dc(surface); 163 164 SetGraphicsMode(m_hdc, GM_ADVANCED); // We need this call for themes to honor world transforms. 165 } 166 167 void GraphicsContextPlatformPrivate::flush() 168 { 169 cairo_surface_t* surface = cairo_win32_surface_create(m_hdc); 170 cairo_surface_flush(surface); 171 cairo_surface_destroy(surface); 172 } 173 174 } 175