1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "ui/gfx/blit.h" 6 7 #include "base/logging.h" 8 #include "build/build_config.h" 9 #include "skia/ext/platform_canvas.h" 10 #include "ui/gfx/point.h" 11 #include "ui/gfx/rect.h" 12 #include "ui/gfx/vector2d.h" 13 14 #if defined(USE_CAIRO) 15 #if defined(OS_OPENBSD) 16 #include <cairo.h> 17 #elif defined(OS_POSIX) && !defined(OS_MACOSX) && !defined(OS_ANDROID) 18 #include <cairo/cairo.h> 19 #endif 20 #endif 21 22 #if defined(OS_MACOSX) 23 #include "base/mac/scoped_cftyperef.h" 24 #endif 25 26 namespace gfx { 27 28 namespace { 29 30 // Returns true if the given canvas has any part of itself clipped out or 31 // any non-identity tranform. 32 bool HasClipOrTransform(SkCanvas& canvas) { 33 if (!canvas.getTotalMatrix().isIdentity()) 34 return true; 35 36 if (!canvas.isClipRect()) 37 return true; 38 39 // Now we know the clip is a regular rectangle, make sure it covers the 40 // entire canvas. 41 SkIRect clip_bounds; 42 canvas.getClipDeviceBounds(&clip_bounds); 43 44 SkImageInfo info; 45 size_t row_bytes; 46 void* pixels = canvas.accessTopLayerPixels(&info, &row_bytes); 47 DCHECK(pixels); 48 if (!pixels) 49 return true; 50 51 if (clip_bounds.fLeft != 0 || clip_bounds.fTop != 0 || 52 clip_bounds.fRight != info.width() || 53 clip_bounds.fBottom != info.height()) 54 return true; 55 56 return false; 57 } 58 59 } // namespace 60 61 void BlitContextToContext(NativeDrawingContext dst_context, 62 const Rect& dst_rect, 63 NativeDrawingContext src_context, 64 const Point& src_origin) { 65 #if defined(OS_WIN) 66 BitBlt(dst_context, dst_rect.x(), dst_rect.y(), 67 dst_rect.width(), dst_rect.height(), 68 src_context, src_origin.x(), src_origin.y(), SRCCOPY); 69 #elif defined(OS_MACOSX) 70 // Only translations and/or vertical flips in the source context are 71 // supported; more complex source context transforms will be ignored. 72 73 // If there is a translation on the source context, we need to account for 74 // it ourselves since CGBitmapContextCreateImage will bypass it. 75 Rect src_rect(src_origin, dst_rect.size()); 76 CGAffineTransform transform = CGContextGetCTM(src_context); 77 bool flipped = fabs(transform.d + 1) < 0.0001; 78 CGFloat delta_y = flipped ? CGBitmapContextGetHeight(src_context) - 79 transform.ty 80 : transform.ty; 81 src_rect.Offset(transform.tx, delta_y); 82 83 base::ScopedCFTypeRef<CGImageRef> src_image( 84 CGBitmapContextCreateImage(src_context)); 85 base::ScopedCFTypeRef<CGImageRef> src_sub_image( 86 CGImageCreateWithImageInRect(src_image, src_rect.ToCGRect())); 87 CGContextDrawImage(dst_context, dst_rect.ToCGRect(), src_sub_image); 88 #elif defined(USE_CAIRO) 89 // Only translations in the source context are supported; more complex 90 // source context transforms will be ignored. 91 cairo_save(dst_context); 92 double surface_x = src_origin.x(); 93 double surface_y = src_origin.y(); 94 cairo_user_to_device(src_context, &surface_x, &surface_y); 95 cairo_set_source_surface(dst_context, cairo_get_target(src_context), 96 dst_rect.x()-surface_x, dst_rect.y()-surface_y); 97 cairo_rectangle(dst_context, dst_rect.x(), dst_rect.y(), 98 dst_rect.width(), dst_rect.height()); 99 cairo_clip(dst_context); 100 cairo_paint(dst_context); 101 cairo_restore(dst_context); 102 #else 103 NOTIMPLEMENTED(); 104 #endif 105 } 106 107 void BlitContextToCanvas(SkCanvas *dst_canvas, 108 const Rect& dst_rect, 109 NativeDrawingContext src_context, 110 const Point& src_origin) { 111 DCHECK(skia::SupportsPlatformPaint(dst_canvas)); 112 BlitContextToContext(skia::BeginPlatformPaint(dst_canvas), dst_rect, 113 src_context, src_origin); 114 skia::EndPlatformPaint(dst_canvas); 115 } 116 117 void BlitCanvasToContext(NativeDrawingContext dst_context, 118 const Rect& dst_rect, 119 SkCanvas *src_canvas, 120 const Point& src_origin) { 121 DCHECK(skia::SupportsPlatformPaint(src_canvas)); 122 BlitContextToContext(dst_context, dst_rect, 123 skia::BeginPlatformPaint(src_canvas), src_origin); 124 skia::EndPlatformPaint(src_canvas); 125 } 126 127 void BlitCanvasToCanvas(SkCanvas *dst_canvas, 128 const Rect& dst_rect, 129 SkCanvas *src_canvas, 130 const Point& src_origin) { 131 DCHECK(skia::SupportsPlatformPaint(dst_canvas)); 132 DCHECK(skia::SupportsPlatformPaint(src_canvas)); 133 BlitContextToContext(skia::BeginPlatformPaint(dst_canvas), dst_rect, 134 skia::BeginPlatformPaint(src_canvas), src_origin); 135 skia::EndPlatformPaint(src_canvas); 136 skia::EndPlatformPaint(dst_canvas); 137 } 138 139 void ScrollCanvas(SkCanvas* canvas, 140 const gfx::Rect& in_clip, 141 const gfx::Vector2d& offset) { 142 DCHECK(!HasClipOrTransform(*canvas)); // Don't support special stuff. 143 #if defined(OS_WIN) 144 // If we have a PlatformCanvas, we should use ScrollDC. Otherwise, fall 145 // through to the software implementation. 146 if (skia::SupportsPlatformPaint(canvas)) { 147 skia::ScopedPlatformPaint scoped_platform_paint(canvas); 148 HDC hdc = scoped_platform_paint.GetPlatformSurface(); 149 150 RECT damaged_rect; 151 RECT r = in_clip.ToRECT(); 152 ScrollDC(hdc, offset.x(), offset.y(), NULL, &r, NULL, &damaged_rect); 153 return; 154 } 155 #endif // defined(OS_WIN) 156 // For non-windows, always do scrolling in software. 157 // Cairo has no nice scroll function so we do our own. On Mac it's possible to 158 // use platform scroll code, but it's complex so we just use the same path 159 // here. Either way it will be software-only, so it shouldn't matter much. 160 SkBitmap& bitmap = const_cast<SkBitmap&>( 161 skia::GetTopDevice(*canvas)->accessBitmap(true)); 162 SkAutoLockPixels lock(bitmap); 163 164 // We expect all coords to be inside the canvas, so clip here. 165 gfx::Rect clip = gfx::IntersectRects( 166 in_clip, gfx::Rect(0, 0, bitmap.width(), bitmap.height())); 167 168 // Compute the set of pixels we'll actually end up painting. 169 gfx::Rect dest_rect = gfx::IntersectRects(clip + offset, clip); 170 if (dest_rect.size().IsEmpty()) 171 return; // Nothing to do. 172 173 // Compute the source pixels that will map to the dest_rect 174 gfx::Rect src_rect = dest_rect - offset; 175 176 size_t row_bytes = dest_rect.width() * 4; 177 if (offset.y() > 0) { 178 // Data is moving down, copy from the bottom up. 179 for (int y = dest_rect.height() - 1; y >= 0; y--) { 180 memcpy(bitmap.getAddr32(dest_rect.x(), dest_rect.y() + y), 181 bitmap.getAddr32(src_rect.x(), src_rect.y() + y), 182 row_bytes); 183 } 184 } else if (offset.y() < 0) { 185 // Data is moving up, copy from the top down. 186 for (int y = 0; y < dest_rect.height(); y++) { 187 memcpy(bitmap.getAddr32(dest_rect.x(), dest_rect.y() + y), 188 bitmap.getAddr32(src_rect.x(), src_rect.y() + y), 189 row_bytes); 190 } 191 } else if (offset.x() != 0) { 192 // Horizontal-only scroll. We can do it in either top-to-bottom or bottom- 193 // to-top, but have to be careful about the order for copying each row. 194 // Fortunately, memmove already handles this for us. 195 for (int y = 0; y < dest_rect.height(); y++) { 196 memmove(bitmap.getAddr32(dest_rect.x(), dest_rect.y() + y), 197 bitmap.getAddr32(src_rect.x(), src_rect.y() + y), 198 row_bytes); 199 } 200 } 201 } 202 203 } // namespace gfx 204
