Compute pageScaleFactor on page so that fixed layout page fits width of window.

content/renderer/render_view.h

 // 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 CONTENT_RENDERER_RENDER_VIEW_H_
 #define CONTENT_RENDERER_RENDER_VIEW_H_
 #pragma once
 
 #include <deque>
 #include <map>
@@ skipping 132 matching lines @@
 class WebStorageNamespace;
 class WebURLLoader;
 class WebURLRequest;
 class WebView;
 struct WebContextMenuData;
 struct WebFileChooserParams;
 struct WebFindOptions;
 struct WebMediaPlayerAction;
 struct WebPluginParams;
 struct WebPoint;
+struct WebRect;
 struct WebWindowFeatures;
 }
 
 // We need to prevent a page from trying to create infinite popups. It is not
 // as simple as keeping a count of the number of immediate children
 // popups. Having an html file that window.open()s itself would create
 // an unlimited chain of RenderViews who only have one RenderView child.
 //
 // Therefore, each new top level RenderView creates a new counter and shares it
 // with all its children and grandchildren popup RenderViews created with
@@ skipping 201 matching lines @@
       WebKit::WebFrame* creator,
       const WebKit::WebURLRequest& request,
       const WebKit::WebWindowFeatures& features,
       const WebKit::WebString& frame_name);
   virtual WebKit::WebWidget* createPopupMenu(WebKit::WebPopupType popup_type);
   virtual WebKit::WebWidget* createPopupMenu(
       const WebKit::WebPopupMenuInfo& info);
   virtual WebKit::WebExternalPopupMenu* createExternalPopupMenu(
       const WebKit::WebPopupMenuInfo& popup_menu_info,
       WebKit::WebExternalPopupMenuClient* popup_menu_client);
+  virtual WebKit::WebRect getDeviceRect() const;
   virtual WebKit::WebStorageNamespace* createSessionStorageNamespace(
       unsigned quota);
   virtual void didAddMessageToConsole(
       const WebKit::WebConsoleMessage& message,
       const WebKit::WebString& source_name,
       unsigned source_line);
   virtual void printPage(WebKit::WebFrame* frame);
   virtual WebKit::WebNotificationPresenter* notificationPresenter();
   virtual bool enumerateChosenDirectory(
       const WebKit::WebString& path,
@@ skipping 242 matching lines @@
   // RenderWidget overrides:
   virtual void Close();
   virtual void OnResize(const gfx::Size& new_size,
                         const gfx::Rect& resizer_rect);
   virtual void DidInitiatePaint();
   virtual webkit::ppapi::PluginInstance* GetBitmapForOptimizedPluginPaint(
       const gfx::Rect& paint_bounds,
       TransportDIB** dib,
       gfx::Rect* location,
       gfx::Rect* clip);
+  virtual gfx::Size GetContentSize();
+  virtual float GetPageScaleFactor();
   virtual gfx::Point GetScrollOffset();
   virtual void DidHandleKeyEvent();
   virtual void DidHandleMouseEvent(const WebKit::WebMouseEvent& event);
   virtual void OnSetFocus(bool enable);
   virtual void OnWasHidden();
   virtual void OnWasRestored(bool needs_repainting);
   virtual bool SupportsAsynchronousSwapBuffers() OVERRIDE;
   virtual void OnImeSetComposition(
       const string16& text,
       const std::vector<WebKit::WebCompositionUnderline>& underlines,
@@ skipping 232 matching lines @@
 
   // Misc private functions ----------------------------------------------------
 
   void AltErrorPageFinished(WebKit::WebFrame* frame,
                             const WebKit::WebURLError& original_error,
                             const std::string& html);
 
   // Check whether the preferred size has changed.
   void CheckPreferredSize();
 
+  // Return the offset, restricted to the document area at the given scale.
+  // (The offset is in the coordinate space of the new scale).
+  gfx::Point ClampOffsetAtScale(const gfx::Point& offset, float scale);
+
+  // Get the scale when the document is fully zoomed out (minimum scale).
+  float ComputeOverviewScale(gfx::Size content_size);
+
+  // Compute the scale within min/max limits.
+  float ComputeScaleWithinLimits(float scale);
+
   // This callback is triggered when DownloadFavicon completes, either
   // succesfully or with a failure. See DownloadFavicon for more
   // details.
   void DidDownloadFavicon(webkit_glue::ImageResourceFetcher* fetcher,
                           const SkBitmap& image);
 
   // Requests to download a favicon image. When done, the RenderView
   // is notified by way of DidDownloadFavicon. Returns true if the
   // request was successfully started, false otherwise. id is used to
   // uniquely identify the request and passed back to the
@@ skipping 20 matching lines @@
 
   // Returns false unless this is a top-level navigation that crosses origins.
   bool IsNonLocalTopLevelNavigation(const GURL& url,
                                     WebKit::WebFrame* frame,
                                     WebKit::WebNavigationType type);
 
   bool MaybeLoadAlternateErrorPage(WebKit::WebFrame* frame,
                                    const WebKit::WebURLError& error,
                                    bool replace);
 
+  // Scales current scroll offset to a new factor.
+  void SetPageScaleFactor(float scale);
+
+  // Moves to the scroll offset (should be provided in the new scale, not the
+  // previous one).
+  void SetPageScaleFactorAndScroll(float scale, const gfx::Point& offset);
+
+  // Keeps Keeps the anchor (in window coordinates) in a stable position on the

[jam, 2011/09/02 17:11:41]

nit Keeps Keeps

[Fady Samuel, 2011/09/08 23:46:39]

Done.

+  // screen.
+  void SetPageScaleFactorWithAnchor(float scale,
+                                    const gfx::Point& window_anchor);
+
   // Starts nav_state_sync_timer_ if it isn't already running.
   void StartNavStateSyncTimerIfNecessary();
 
   // Dispatches the current navigation state to the browser. Called on a
   // periodic timer so we don't send too many messages.
   void SyncNavigationState();
 
   // Dispatches the current state of selection on the webpage to the browser if
   // it has changed.
   // TODO(varunjain): delete this method once we figure out how to keep
   // selection handles in sync with the webpage.
   void SyncSelectionIfRequired();
 
+  // If not already initialized, initialize the scale to the overview scale.
+  bool TryInitializeScale();
+
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
   void UpdateFontRenderingFromRendererPrefs();
 #else
   void UpdateFontRenderingFromRendererPrefs() {}
 #endif
 
+  void UpdatePageScale(gfx::Size new_content_size);
+
   // Update the target url and tell the browser that the target URL has changed.
   // If |url| is empty, show |fallback_url|.
   void UpdateTargetURL(const GURL& url, const GURL& fallback_url);
 
   // ---------------------------------------------------------------------------
   // ADDING NEW FUNCTIONS? Please keep private functions alphabetized and put
   // it in the same order in the .cc file as it was in the header.
   // ---------------------------------------------------------------------------
 
   // Settings ------------------------------------------------------------------
@@ skipping 213 matching lines @@
       pending_accessibility_notifications_;
 
   // Set if we are waiting for a accessibility notification ack.
   bool accessibility_ack_pending_;
 
   // Dispatches all P2P socket used by the renderer.
   content::P2PSocketDispatcher* p2p_socket_dispatcher_;
 
   DevToolsAgent* devtools_agent_;
 
+  // Scaling and Fixed Layout --------------------------------------------------
+
+  // viewport scale related fields.
+  bool user_scalable_;
+  float minimum_scale_;
+  float maximum_scale_;

[jamesr, 2011/09/02 17:43:09]

why are these member variables? from what I can tell they are always set to the
defaults

[Fady Samuel, 2011/09/08 23:46:39]

These will be used in an upcoming patch once the viewport meta tag is enabled.

+
   // Misc ----------------------------------------------------------------------
 
   // The current and pending file chooser completion objects. If the queue is
   // nonempty, the first item represents the currently running file chooser
   // callback, and the remaining elements are the other file chooser completion
   // still waiting to be run (in order).
   struct PendingFileChooser;
   std::deque< linked_ptr<PendingFileChooser> > file_chooser_completions_;
 
   // The current directory enumeration callback
@@ skipping 51 matching lines @@
   // bunch of stuff, you should probably create a helper class and put your
   // data and methods on that to avoid bloating RenderView more.  You can use
   // the Observer interface to filter IPC messages and receive frame change
   // notifications.
   // ---------------------------------------------------------------------------
 
   DISALLOW_COPY_AND_ASSIGN(RenderView);
 };
 
 #endif  // CONTENT_RENDERER_RENDER_VIEW_H_