Move DIP translation from ui/aura to ui/compositor

ui/gfx/compositor/compositor.cc

Index: ui/gfx/compositor/compositor.cc
diff --git a/ui/gfx/compositor/compositor.cc b/ui/gfx/compositor/compositor.cc
index 3a8942a46bc72b742d834a77b51c141e6fba20ed..98efe7584705916a9e6b05e53628d8aa921576f0 100644
--- a/ui/gfx/compositor/compositor.cc
+++ b/ui/gfx/compositor/compositor.cc
@@ -15,6 +15,7 @@
 #include "ui/gfx/compositor/compositor_observer.h"
 #include "ui/gfx/compositor/compositor_switches.h"
 #include "ui/gfx/compositor/layer.h"
+#include "ui/gfx/compositor/dip_util.h"
 #include "ui/gfx/compositor/test_web_graphics_context_3d.h"
 #include "ui/gfx/gl/gl_context.h"
 #include "ui/gfx/gl/gl_implementation.h"
@@ -119,14 +120,13 @@ Texture::~Texture() {
 }
 
 Compositor::Compositor(CompositorDelegate* delegate,
-                       gfx::AcceleratedWidget widget,
-                       const gfx::Size& size)
+                       gfx::AcceleratedWidget widget)
     : delegate_(delegate),
-      size_(size),
       root_layer_(NULL),
       widget_(widget),
       root_web_layer_(WebKit::WebLayer::create()),
-      swap_posted_(false) {
+      swap_posted_(false),
+      device_scale_factor_(0.0f) {
   WebKit::WebLayerTreeView::Settings settings;
   CommandLine* command_line = CommandLine::ForCurrentProcess();
   settings.showFPSCounter =
@@ -142,7 +142,6 @@ Compositor::Compositor(CompositorDelegate* delegate,
 
   host_.initialize(this, root_web_layer_, settings);
   root_web_layer_.setAnchorPoint(WebKit::WebFloatPoint(0.f, 0.f));
-  WidgetSizeChanged(size_);
 }
 
 Compositor::~Compositor() {
@@ -210,32 +209,47 @@ void Compositor::ScheduleFullDraw() {
   host_.setNeedsRedraw();
 }
 
-bool Compositor::ReadPixels(SkBitmap* bitmap, const gfx::Rect& bounds) {
-  if (bounds.right() > size().width() || bounds.bottom() > size().height())
+bool Compositor::ReadPixels(SkBitmap* bitmap,
+                            const gfx::Rect& bounds_in_pixel) {
+  if (bounds_in_pixel.right() > size().width() ||
+      bounds_in_pixel.bottom() > size().height())
     return false;
   // Convert to OpenGL coordinates.
-  gfx::Point new_origin(bounds.x(),
-                        size().height() - bounds.height() - bounds.y());
+  gfx::Point new_origin(
+      bounds_in_pixel.x(),
+      size().height() - bounds_in_pixel.height() - bounds_in_pixel.y());
 
   bitmap->setConfig(SkBitmap::kARGB_8888_Config,
-                    bounds.width(), bounds.height());
+                    bounds_in_pixel.width(), bounds_in_pixel.height());
   bitmap->allocPixels();
   SkAutoLockPixels lock_image(*bitmap);
   unsigned char* pixels = static_cast<unsigned char*>(bitmap->getPixels());
-  if (host_.compositeAndReadback(pixels,
-                                 gfx::Rect(new_origin, bounds.size()))) {
-    SwizzleRGBAToBGRAAndFlip(pixels, bounds.size());
+  if (host_.compositeAndReadback(
+          pixels, gfx::Rect(new_origin, bounds_in_pixel.size()))) {
+    SwizzleRGBAToBGRAAndFlip(pixels, bounds_in_pixel.size());
     return true;
   }
   return false;
 }
 
-void Compositor::WidgetSizeChanged(const gfx::Size& size) {
-  if (size.IsEmpty())
+void Compositor::WidgetScaleOrSizeChanged(float scale,
+                                          const gfx::Size& size_in_pixel) {
+  if (size_in_pixel.IsEmpty() || scale <= 0)
     return;
-  size_ = size;
-  host_.setViewportSize(size_);
-  root_web_layer_.setBounds(size_);
+  size_ = size_in_pixel;
+  host_.setViewportSize(size_in_pixel);
+  root_web_layer_.setBounds(size_in_pixel);
+
+  if (device_scale_factor_ != scale && IsDIPEnabled()) {
+    device_scale_factor_ = scale;
+    scale_translate_.matrix().set3x3(scale, 0, 0,
+                                     0, scale, 0,
+                                     0, 0, 1);
+    CHECK(scale_translate_.matrix().invert(
+        &invese_scale_translate_.matrix()));
+     if (root_layer_)

[piman, 2012/05/04 18:46:06]

nit: indentation?

+      root_layer_->UpdateLayerSize();
+  }
 }
 
 void Compositor::AddObserver(CompositorObserver* observer) {
@@ -267,6 +281,17 @@ void Compositor::OnSwapBuffersAborted() {
   }
 }
 
+Transform Compositor::GetTranslateTransform(
+    const Transform& transform,
+    const gfx::Point& offset) {
+  ui::Transform ret;
+  ret.ConcatTransform(invese_scale_translate_);

[piman, 2012/05/04 18:46:06]

nit: you probably want to start with ret=inverse_scale_translate_ and
concatenate the other transforms. It saves a trivial matrix multiply.

+  ret.ConcatTransform(transform);
+  ret.ConcatTranslate(offset.x(), offset.y());
+  ret.ConcatTransform(scale_translate_);
+  return ret;
+}
+
 void Compositor::updateAnimations(double frameBeginTime) {
 }