ui/gfx/canvas_paint_win.cc

   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 "base/basictypes.h"
   6 #include "base/compiler_specific.h"
   7 #include "ui/gfx/canvas.h"
   8 #include "ui/gfx/canvas_skia_paint.h"
   9 #include "ui/gfx/rect.h"
  10
  11 namespace gfx {
  12
  13 CanvasSkiaPaint::CanvasSkiaPaint(HWND hwnd, HDC dc, const PAINTSTRUCT& ps)
  14     : hwnd_(hwnd),
  15       paint_dc_(dc) {
  16   memset(&ps_, 0, sizeof(ps_));
  17   ps_.rcPaint.left = ps.rcPaint.left;
  18   ps_.rcPaint.right = ps.rcPaint.right;
  19   ps_.rcPaint.top = ps.rcPaint.top;
  20   ps_.rcPaint.bottom = ps.rcPaint.bottom;
  21   Init(true);
  22 }
  23
  24 CanvasSkiaPaint::CanvasSkiaPaint(HDC dc, bool opaque, int x, int y,
  25                                  int w, int h)
  26     : hwnd_(NULL),
  27       paint_dc_(dc) {
  28   memset(&ps_, 0, sizeof(ps_));
  29   ps_.rcPaint.left = x;
  30   ps_.rcPaint.right = x + w;
  31   ps_.rcPaint.top = y;
  32   ps_.rcPaint.bottom = y + h;
  33   Init(opaque);
  34 }
  35
  36 CanvasSkiaPaint::~CanvasSkiaPaint() {
  37   if (!is_empty()) {
  38     skia::PlatformCanvas* canvas = platform_canvas();
  39     canvas->restoreToCount(1);
  40     // Commit the drawing to the screen
  41     skia::DrawToNativeContext(canvas, paint_dc_, ps_.rcPaint.left,
  42                               ps_.rcPaint.top, NULL);
  43   }
  44 }
  45
  46 gfx::Rect CanvasSkiaPaint::GetInvalidRect() const {
  47   return gfx::Rect(paint_struct().rcPaint);
  48 }
  49
  50 void CanvasSkiaPaint::Init(bool opaque) {
  51   // FIXME(brettw) for ClearType, we probably want to expand the bounds of
  52   // painting by one pixel so that the boundaries will be correct (ClearType
  53   // text can depend on the adjacent pixel). Then we would paint just the
  54   // inset pixels to the screen.
  55   const int width = ps_.rcPaint.right - ps_.rcPaint.left;
  56   const int height = ps_.rcPaint.bottom - ps_.rcPaint.top;
  57
  58   RecreateBackingCanvas(gfx::Size(width, height),
  59       gfx::win::GetDeviceScaleFactor(),
  60       opaque);
  61   skia::PlatformCanvas* canvas = platform_canvas();
  62
  63   canvas->clear(SkColorSetARGB(0, 0, 0, 0));
  64
  65   // This will bring the canvas into the screen coordinate system for the
  66   // dirty rect
  67   canvas->translate(
  68       -ps_.rcPaint.left / gfx::win::GetDeviceScaleFactor(),
  69       -ps_.rcPaint.top / gfx::win::GetDeviceScaleFactor());
  70 }
  71
  72 }  // namespace gfx