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