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 "DragImage.h" 28 29 #include "BitmapInfo.h" 30 #include "CachedImage.h" 31 #include "GraphicsContext.h" 32 #include "GraphicsContextPlatformPrivateCairo.h" 33 #include "Image.h" 34 #include "RetainPtr.h" 35 #include <cairo-win32.h> 36 #include <windows.h> 37 38 namespace WebCore { 39 40 void deallocContext(PlatformContextCairo* target) 41 { 42 delete target; 43 } 44 45 HBITMAP allocImage(HDC dc, IntSize size, PlatformContextCairo** targetRef) 46 { 47 BitmapInfo bmpInfo = BitmapInfo::create(size); 48 49 LPVOID bits; 50 HBITMAP hbmp = CreateDIBSection(dc, &bmpInfo, DIB_RGB_COLORS, &bits, 0, 0); 51 52 // At this point, we have a Cairo surface that points to a Windows DIB. The DIB interprets 53 // with the opposite meaning of positive Y axis, so everything we draw into this cairo 54 // context is going to be upside down. 55 if (!targetRef) 56 return hbmp; 57 58 cairo_surface_t* bitmapContext = cairo_image_surface_create_for_data((unsigned char*)bits, 59 CAIRO_FORMAT_ARGB32, 60 bmpInfo.bmiHeader.biWidth, 61 bmpInfo.bmiHeader.biHeight, 62 bmpInfo.bmiHeader.biWidth * 4); 63 64 if (!bitmapContext) { 65 DeleteObject(hbmp); 66 return 0; 67 } 68 69 cairo_t* cr = cairo_create(bitmapContext); 70 cairo_surface_destroy(bitmapContext); 71 72 // At this point, we have a Cairo surface that points to a Windows DIB. The DIB interprets 73 // with the opposite meaning of positive Y axis, so everything we draw into this cairo 74 // context is going to be upside down. 75 // 76 // So, we must invert the CTM for the context so that drawing commands will be flipped 77 // before they get written to the internal buffer. 78 cairo_matrix_t matrix; 79 cairo_matrix_init(&matrix, 1.0, 0.0, 0.0, -1.0, 0.0, size.height()); 80 cairo_set_matrix(cr, &matrix); 81 82 *targetRef = new PlatformGraphicsContext(cr); 83 cairo_destroy(cr); 84 85 return hbmp; 86 } 87 88 static cairo_surface_t* createCairoContextFromBitmap(HBITMAP bitmap) 89 { 90 BITMAP info; 91 GetObject(bitmap, sizeof(info), &info); 92 ASSERT(info.bmBitsPixel == 32); 93 94 // At this point, we have a Cairo surface that points to a Windows BITMAP. The BITMAP 95 // has the opposite meaning of positive Y axis, so everything we draw into this cairo 96 // context is going to be upside down. 97 return cairo_image_surface_create_for_data((unsigned char*)info.bmBits, 98 CAIRO_FORMAT_ARGB32, 99 info.bmWidth, 100 info.bmHeight, 101 info.bmWidthBytes); 102 } 103 104 DragImageRef scaleDragImage(DragImageRef image, FloatSize scale) 105 { 106 // FIXME: due to the way drag images are done on windows we need 107 // to preprocess the alpha channel <rdar://problem/5015946> 108 if (!image) 109 return 0; 110 111 IntSize srcSize = dragImageSize(image); 112 IntSize dstSize(static_cast<int>(srcSize.width() * scale.width()), static_cast<int>(srcSize.height() * scale.height())); 113 114 HBITMAP hbmp = 0; 115 HDC dc = GetDC(0); 116 HDC dstDC = CreateCompatibleDC(dc); 117 118 if (!dstDC) 119 goto exit; 120 121 PlatformContextCairo* targetContext; 122 hbmp = allocImage(dstDC, dstSize, &targetContext); 123 if (!hbmp) 124 goto exit; 125 126 cairo_surface_t* srcImage = createCairoContextFromBitmap(image); 127 128 // Scale the target surface to the new image size, and flip it 129 // so that when we set the srcImage as the surface it will draw 130 // right-side-up. 131 cairo_t* cr = targetContext->cr(); 132 cairo_translate(cr, 0, dstSize.height()); 133 cairo_scale(cr, scale.width(), -scale.height()); 134 cairo_set_source_surface(cr, srcImage, 0.0, 0.0); 135 136 // Now we can paint and get the correct result 137 cairo_paint(cr); 138 139 cairo_surface_destroy(srcImage); 140 deallocContext(targetContext); 141 ::DeleteObject(image); 142 image = 0; 143 144 exit: 145 if (!hbmp) 146 hbmp = image; 147 if (dstDC) 148 DeleteDC(dstDC); 149 ReleaseDC(0, dc); 150 return hbmp; 151 } 152 153 DragImageRef createDragImageFromImage(Image* img) 154 { 155 HBITMAP hbmp = 0; 156 HDC dc = GetDC(0); 157 HDC workingDC = CreateCompatibleDC(dc); 158 if (!workingDC) 159 goto exit; 160 161 PlatformContextCairo* drawContext = 0; 162 hbmp = allocImage(workingDC, img->size(), &drawContext); 163 if (!hbmp) 164 goto exit; 165 166 if (!drawContext) { 167 ::DeleteObject(hbmp); 168 hbmp = 0; 169 } 170 171 cairo_t* cr = drawContext->cr(); 172 cairo_set_source_rgb(cr, 1.0, 0.0, 1.0); 173 cairo_fill_preserve(cr); 174 175 cairo_surface_t* srcImage = img->nativeImageForCurrentFrame(); 176 177 // Draw the image. 178 cairo_set_source_surface(cr, srcImage, 0.0, 0.0); 179 cairo_paint(cr); 180 181 deallocContext(drawContext); 182 183 exit: 184 if (workingDC) 185 DeleteDC(workingDC); 186 ReleaseDC(0, dc); 187 return hbmp; 188 } 189 190 } 191
