Revert 164660 - Change CanvasPaintT from a template to just a subclass of gfx::Canvas. Greatly

simplifies source-code-readability, and will allow us to move the impl into
a .cc file, rather than carry it to every call-site.

This is also a necessary precursor to a subsequent change to remove initialize()
from PlatformCanvas, and make it just a typedef for SkCanvas.
Review URL: https://codereview.chromium.org/11193037

TBR=reed@google.com
Review URL: https://codereview.chromium.org/11347017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@164666 0039d316-1c4b-4281-b951-d872f2087c98

7 files changed, 33 insertions, 417 deletions

diff --git a/ui/gfx/canvas_paint_gtk.cc b/ui/gfx/canvas_paint_gtk.cc
deleted file mode 100644
index e164cdc..0000000
--- a/ui/gfx/canvas_paint_gtk.cc
+++ /dev/null
@@ -1,71 +0,0 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-#include "ui/gfx/canvas.h"
-#include "ui/gfx/canvas_skia_paint.h"
-#include "ui/gfx/rect.h"
-
-namespace gfx {
-
-CanvasSkiaPaint::CanvasSkiaPaint(GdkEventExpose* event)
-    : context_(NULL),
-      window_(event->window),
-      region_(gdk_region_copy(event->region)),
-      composite_alpha_(false) {
-  Init(true);
-}
-
-CanvasSkiaPaint::CanvasSkiaPaint(GdkEventExpose* event, bool opaque)
-    : context_(NULL),
-      window_(event->window),
-      region_(gdk_region_copy(event->region)),
-      composite_alpha_(false) {
-  Init(opaque);
-}
-
-CanvasSkiaPaint::~CanvasSkiaPaint() {
-  if (!is_empty()) {
-    platform_canvas()->restoreToCount(1);
-
-    // Blit the dirty rect to the window.
-    CHECK(window_);
-    cairo_t* cr = gdk_cairo_create(window_);
-    CHECK(cr);
-    if (composite_alpha_)
-      cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
-    cairo_surface_t* source_surface = cairo_get_target(context_);
-    CHECK(source_surface);
-    // Flush cairo's cache of the surface.
-    cairo_surface_mark_dirty(source_surface);
-    GdkRectangle bounds = rectangle();
-    cairo_set_source_surface(cr, source_surface, bounds.x, bounds.y);
-    gdk_cairo_region(cr, region_);
-    cairo_fill(cr);
-    cairo_destroy(cr);
-  }
-
-  gdk_region_destroy(region_);
-}
-
-void CanvasSkiaPaint::Init(bool opaque) {
-  GdkRectangle bounds = rectangle();
-  skia::PlatformCanvas* canvas = platform_canvas();
-  if (!canvas->initialize(bounds.width, bounds.height, opaque, NULL)) {
-    // Cause a deliberate crash;
-    CHECK(false);
-  }
-  // No need to clear the canvas, because cairo automatically performs the
-  // clear.
-
-  // Need to translate so that the dirty region appears at the origin of the
-  // surface.
-  canvas->translate(-SkIntToScalar(bounds.x), -SkIntToScalar(bounds.y));
-
-  context_ = skia::BeginPlatformPaint(canvas);
-}
-
-} // namespace gfx
-
diff --git a/ui/gfx/canvas_paint_gtk.h b/ui/gfx/canvas_paint_gtk.h
deleted file mode 100644
index db64e49..0000000
--- a/ui/gfx/canvas_paint_gtk.h
+++ /dev/null
@@ -1,62 +0,0 @@
-
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef UI_GFX_CANVAS_PAINT_LINUX_H_
-#define UI_GFX_CANVAS_PAINT_LINUX_H_
-
-#include "base/logging.h"
-#include "skia/ext/platform_canvas.h"
-#include "ui/gfx/canvas.h"
-#include <gdk/gdk.h>
-
-namespace gfx {
-
-// A class designed to translate skia painting into a region in a GdkWindow.
-// On construction, it will set up a context for painting into, and on
-// destruction, it will commit it to the GdkWindow.
-// Note: The created context is always inialized to (0, 0, 0, 0).
-class CanvasSkiaPaint : public Canvas {
- public:
-  // This constructor assumes the result is opaque.
-  explicit CanvasSkiaPaint(GdkEventExpose* event);
-  CanvasSkiaPaint(GdkEventExpose* event, bool opaque);
-  virtual ~CanvasSkiaPaint();
-
-  // Sets whether the bitmap is composited in such a way that the alpha channel
-  // is honored. This is only useful if you've enabled an RGBA colormap on the
-  // widget. The default is false.
-  void set_composite_alpha(bool composite_alpha) {
-    composite_alpha_ = composite_alpha;
-  }
-
-  // Returns true if the invalid region is empty. The caller should call this
-  // function to determine if anything needs painting.
-  bool is_empty() const {
-    return gdk_region_empty(region_);
-  }
-
-  GdkRectangle rectangle() const {
-    GdkRectangle bounds;
-    gdk_region_get_clipbox(region_, &bounds);
-    return bounds;
-  }
-
- private:
-  void Init(bool opaque);
-
-  cairo_t* context_;
-  GdkWindow* window_;
-  GdkRegion* region_;
-  // See description above setter.
-  bool composite_alpha_;
-
-  // Disallow copy and assign.
-  CanvasSkiaPaint(const CanvasSkiaPaint&);
-  CanvasSkiaPaint& operator=(const CanvasSkiaPaint&);
-};
-
-}  // namespace gfx
-
-#endif  // UI_GFX_CANVAS_PAINT_LINUX_H_
diff --git a/ui/gfx/canvas_paint_mac.h b/ui/gfx/canvas_paint_mac.h
deleted file mode 100644
index 6d19565..0000000
--- a/ui/gfx/canvas_paint_mac.h
+++ /dev/null
@@ -1,59 +0,0 @@
-
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef UI_GFX_CANVAS_PAINT_MAC_H_
-#define UI_GFX_CANVAS_PAINT_MAC_H_
-
-#include "skia/ext/platform_canvas.h"
-#include "ui/gfx/canvas.h"
-
-#import <Cocoa/Cocoa.h>
-
-namespace gfx {
-
-// A class designed to translate skia painting into a region to the current
-// graphics context.  On construction, it will set up a context for painting
-// into, and on destruction, it will commit it to the current context.
-// Note: The created context is always inialized to (0, 0, 0, 0).
-class CanvasSkiaPaint : public Canvas {
- public:
-  // This constructor assumes the result is opaque.
-  explicit CanvasSkiaPaint(NSRect dirtyRect);
-  CanvasSkiaPaint(NSRect dirtyRect, bool opaque);
-  virtual ~CanvasSkiaPaint();
-
-  // If true, the data painted into the CanvasSkiaPaint is blended onto the
-  // current context, else it is copied.
-  void set_composite_alpha(bool composite_alpha) {
-    composite_alpha_ = composite_alpha;
-  }
-
-  // Returns true if the invalid region is empty. The caller should call this
-  // function to determine if anything needs painting.
-  bool is_empty() const {
-    return NSIsEmptyRect(rectangle_);
-  }
-
-  const NSRect& rectangle() const {
-    return rectangle_;
-  }
-
- private:
-  void Init(bool opaque);
-
-  CGContext* context_;
-  NSRect rectangle_;
-  // See description above setter.
-  bool composite_alpha_;
-
-  // Disallow copy and assign.
-  CanvasSkiaPaint(const CanvasSkiaPaint&);
-  CanvasSkiaPaint& operator=(const CanvasSkiaPaint&);
-};
-
-}  // namespace gfx
-
-
-#endif  // UI_GFX_CANVAS_PAINT_MAC_H_
diff --git a/ui/gfx/canvas_paint_mac.mm b/ui/gfx/canvas_paint_mac.mm
deleted file mode 100644
index 83c5a9bb..0000000
--- a/ui/gfx/canvas_paint_mac.mm
+++ /dev/null
@@ -1,76 +0,0 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "ui/gfx/canvas_paint_mac.h"
-#include "ui/gfx/size.h"
-
-namespace gfx {
-
-CanvasSkiaPaint::CanvasSkiaPaint(NSRect dirtyRect)
-    : context_(NULL),
-      rectangle_(dirtyRect),
-      composite_alpha_(false) {
-  Init(true);
-}
-
-CanvasSkiaPaint::CanvasSkiaPaint(NSRect dirtyRect, bool opaque)
-    : context_(NULL),
-      rectangle_(dirtyRect),
-      composite_alpha_(false) {
-  Init(opaque);
-}
-
-CanvasSkiaPaint::~CanvasSkiaPaint() {
-  if (!is_empty()) {
-    platform_canvas()->restoreToCount(1);
-
-    // Blit the dirty rect to the current context.
-    CGImageRef image = CGBitmapContextCreateImage(context_);
-    CGRect dest_rect = NSRectToCGRect(rectangle_);
-
-    CGContextRef destination_context =
-        (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
-    CGContextSaveGState(destination_context);
-    CGContextSetBlendMode(
-        destination_context,
-        composite_alpha_ ? kCGBlendModeNormal : kCGBlendModeCopy);
-
-    if ([[NSGraphicsContext currentContext] isFlipped]) {
-      // Mirror context on the target's rect middle scanline.
-      CGContextTranslateCTM(destination_context, 0.0, NSMidY(rectangle_));
-      CGContextScaleCTM(destination_context, 1.0, -1.0);
-      CGContextTranslateCTM(destination_context, 0.0, -NSMidY(rectangle_));
-    }
-
-    CGContextDrawImage(destination_context, dest_rect, image);
-    CGContextRestoreGState(destination_context);
-
-    CFRelease(image);
-  }
-}
-
-void CanvasSkiaPaint::Init(bool opaque) {
-  CGContextRef destination_context =
-        (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
-  CGRect scaled_unit_rect = CGContextConvertRectToDeviceSpace(
-        destination_context, CGRectMake(0, 0, 1, 1));
-    // Assume that the x scale and the y scale are the same.
-  CGFloat scale = scaled_unit_rect.size.width;
-
-  ui::ScaleFactor scale_factor = ui::GetScaleFactorFromScale(scale);
-  gfx::Size size(NSWidth(rectangle_), NSHeight(rectangle_));
-  this->RecreateBackingCanvas(size, scale_factor, opaque);
-  skia::PlatformCanvas* canvas = platform_canvas();
-  canvas->clear(SkColorSetARGB(0, 0, 0, 0));
-
-    // Need to translate so that the dirty region appears at the origin of the
-    // surface.
-  canvas->translate(-SkDoubleToScalar(NSMinX(rectangle_)),
-                    -SkDoubleToScalar(NSMinY(rectangle_)));
-
-  context_ = skia::GetBitmapContext(skia::GetTopDevice(*canvas));
-}
-
-}  // namespace skia
-
diff --git a/ui/gfx/canvas_paint_win.cc b/ui/gfx/canvas_paint_win.cc
index 27898fc..87ba3f6 100644
--- a/ui/gfx/canvas_paint_win.cc
+++ b/ui/gfx/canvas_paint_win.cc
@@ -5,6 +5,7 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "ui/gfx/canvas.h"
+#include "ui/gfx/canvas_paint.h"
 #include "ui/gfx/canvas_skia_paint.h"
 #include "ui/gfx/rect.h"
 
diff --git a/ui/gfx/canvas_paint_win.h b/ui/gfx/canvas_paint_win.h
deleted file mode 100644
index 07044b5..0000000
--- a/ui/gfx/canvas_paint_win.h
+++ /dev/null
@@ -1,135 +0,0 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef UI_GFX_CANVAS_PAINT_WIN_H_
-#define UI_GFX_CANVAS_PAINT_WIN_H_
-
-#include "skia/ext/platform_canvas.h"
-#include "ui/gfx/canvas.h"
-#include "ui/gfx/canvas_paint.h"
-
-namespace gfx {
-
-// A class designed to help with WM_PAINT operations on Windows. It will
-// do BeginPaint/EndPaint on init/destruction, and will create the bitmap and
-// canvas with the correct size and transform for the dirty rect. The bitmap
-// will be automatically painted to the screen on destruction.
-//
-// You MUST call isEmpty before painting to determine if anything needs
-// painting. Sometimes the dirty rect can actually be empty, and this makes
-// the bitmap functions we call unhappy. The caller should not paint in this
-// case.
-//
-// Therefore, all you need to do is:
-//   case WM_PAINT: {
-//     gfx::PlatformCanvasPaint canvas(hwnd);
-//     if (!canvas.isEmpty()) {
-//       ... paint to the canvas ...
-//     }
-//     return 0;
-//   }
-// Note: The created context is always inialized to (0, 0, 0, 0).
-class CanvasSkiaPaint : public Canvas {
- public:
-  // This constructor assumes the canvas is opaque.
-  explicit CanvasSkiaPaint(HWND hwnd) : hwnd_(hwnd), paint_dc_(NULL),
-    for_paint_(true) {
-    memset(&ps_, 0, sizeof(ps_));
-    initPaint(true);
-  }
-
-  CanvasSkiaPaint(HWND hwnd, bool opaque) : hwnd_(hwnd), paint_dc_(NULL),
-      for_paint_(true) {
-    memset(&ps_, 0, sizeof(ps_));
-    initPaint(opaque);
-  }
-
-  // Creates a CanvasSkiaPaint for the specified region that paints to the
-  // specified dc. This does NOT do BeginPaint/EndPaint.
-  CanvasSkiaPaint(HDC dc, bool opaque, int x, int y, int w, int h)
-      : hwnd_(NULL),
-        paint_dc_(dc),
-        for_paint_(false) {
-    memset(&ps_, 0, sizeof(ps_));
-    ps_.rcPaint.left = x;
-    ps_.rcPaint.right = x + w;
-    ps_.rcPaint.top = y;
-    ps_.rcPaint.bottom = y + h;
-    init(opaque);
-  }
-
-  virtual ~CanvasSkiaPaint() {
-    if (!isEmpty()) {
-      skia::PlatformCanvas* canvas = platform_canvas();
-      canvas->restoreToCount(1);
-      // Commit the drawing to the screen
-      skia::DrawToNativeContext(canvas, paint_dc_, ps_.rcPaint.left,
-                                ps_.rcPaint.top, NULL);
-    }
-    if (for_paint_)
-      EndPaint(hwnd_, &ps_);
-  }
-
-  // Returns true if the invalid region is empty. The caller should call this
-  // function to determine if anything needs painting.
-  bool isEmpty() const {
-    return ps_.rcPaint.right - ps_.rcPaint.left == 0 ||
-           ps_.rcPaint.bottom - ps_.rcPaint.top == 0;
-  }
-
-  // Use to access the Windows painting parameters, especially useful for
-  // getting the bounding rect for painting: paintstruct().rcPaint
-  const PAINTSTRUCT& paintStruct() const {
-    return ps_;
-  }
-
-  // Returns the DC that will be painted to
-  HDC paintDC() const {
-    return paint_dc_;
-  }
-
- protected:
-  HWND hwnd_;
-  HDC paint_dc_;
-  PAINTSTRUCT ps_;
-
- private:
-  void initPaint(bool opaque) {
-    paint_dc_ = BeginPaint(hwnd_, &ps_);
-
-    init(opaque);
-  }
-
-  void init(bool opaque) {
-    skia::PlatformCanvas* canvas = platform_canvas();
-    // FIXME(brettw) for ClearType, we probably want to expand the bounds of
-    // painting by one pixel so that the boundaries will be correct (ClearType
-    // text can depend on the adjacent pixel). Then we would paint just the
-    // inset pixels to the screen.
-    const int width = ps_.rcPaint.right - ps_.rcPaint.left;
-    const int height = ps_.rcPaint.bottom - ps_.rcPaint.top;
-    if (!canvas->initialize(width, height, opaque, NULL)) {
-      // Cause a deliberate crash;
-      __debugbreak();
-      _exit(1);
-    }
-    canvas->clear(SkColorSetARGB(0, 0, 0, 0));
-
-    // This will bring the canvas into the screen coordinate system for the
-    // dirty rect
-    canvas->translate(SkIntToScalar(-ps_.rcPaint.left),
-                      SkIntToScalar(-ps_.rcPaint.top));
-  }
-
-  // If true, this canvas was created for a BeginPaint.
-  const bool for_paint_;
-
-  // Disallow copy and assign.
-  CanvasSkiaPaint(const CanvasSkiaPaint&);
-  CanvasSkiaPaint& operator=(const CanvasSkiaPaint&);
-};
-
-}  // namespace gfx
-
-#endif  // UI_GFX_CANVAS_PAINT_WIN_H_
diff --git a/ui/gfx/canvas_skia_paint.h b/ui/gfx/canvas_skia_paint.h
index 3f21f5c..ad92d94 100644
--- a/ui/gfx/canvas_skia_paint.h
+++ b/ui/gfx/canvas_skia_paint.h
@@ -5,19 +5,37 @@
 #ifndef UI_GFX_CANVAS_SKIA_PAINT_H_
 #define UI_GFX_CANVAS_SKIA_PAINT_H_
 
-// This file provides an easy way to include the appropriate CanvasPaint
-// header file on your platform.
-
-#if defined(WIN32)
-#include "ui/gfx/canvas_paint_win.h"
-#elif defined(__APPLE__)
-#include "ui/gfx/canvas_paint_mac.h"
-#elif defined(__linux__) || defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__sun)
-#if defined(TOOLKIT_GTK)
-#include "ui/gfx/canvas_paint_gtk.h"
-#else
-#error "No canvas paint for this platform"
-#endif
-#endif
+#include "base/logging.h"
+#include "skia/ext/canvas_paint.h"
+#include "ui/gfx/canvas.h"
+#include "ui/gfx/size.h"
+
+// Define a gfx::CanvasSkiaPaint type that wraps our gfx::Canvas like the
+// skia::PlatformCanvasPaint wraps PlatformCanvas.
+
+namespace skia {
+
+template<> inline
+PlatformCanvas* GetPlatformCanvas(skia::CanvasPaintT<gfx::Canvas>* canvas) {
+  PlatformCanvas* platform_canvas = canvas->platform_canvas();
+  DCHECK(platform_canvas);
+  return platform_canvas;
+}
+
+template<> inline
+void RecreateBackingCanvas(skia::CanvasPaintT<gfx::Canvas>* canvas,
+    int width, int height, float scale, bool opaque) {
+  ui::ScaleFactor scale_factor = ui::GetScaleFactorFromScale(scale);
+  canvas->RecreateBackingCanvas(gfx::Size(width, height), scale_factor,
+      opaque);
+}
+
+}  // namespace skia
+
+namespace gfx {
+
+typedef skia::CanvasPaintT<Canvas> CanvasSkiaPaint;
+
+}  // namespace gfx
 
 #endif  // UI_GFX_CANVAS_SKIA_PAINT_H_