Linux: server side backing stores

chrome/browser/renderer_host/backing_store.h

 // Copyright (c) 2006-2008 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 CHROME_BROWSER_RENDERER_HOST_BACKING_STORE_H_
 #define CHROME_BROWSER_RENDERER_HOST_BACKING_STORE_H_
 
 #include "base/basictypes.h"
 #include "base/gfx/rect.h"
 #include "base/gfx/size.h"
 #include "base/process.h"
 #include "build/build_config.h"
 #include "chrome/common/mru_cache.h"
 
 #if defined(OS_WIN)
 #include <windows.h>
-#elif defined(OS_POSIX)
+#elif defined(OS_MACOSX)
 #include "skia/ext/platform_canvas.h"
+#elif defined(OS_LINUX)
+#include "chrome/common/x11_util.h"
 #endif
 
 class RenderWidgetHost;
 class TransportDIB;
 
 // BackingStore ----------------------------------------------------------------
 
 // Represents a backing store for the pixels in a RenderWidgetHost.
 class BackingStore {
  public:
+#if defined(OS_WIN) || defined(OS_MACOSX)
   explicit BackingStore(const gfx::Size& size);
+#elif defined(OS_LINUX)
+  // Create a backing store on the X server.
+  //   size: the size of the server-side pixmap
+  //   x_connection: the display to target
+  //   depth: the depth of the X window which will be drawn into
+  //   visual: An Xlib Visual describing the format of the target window
+  //   parent_window: The X id of the target window
+  //   use_shared_memory: if true, the X server is local
+  BackingStore(const gfx::Size& size, Display* x_connection, int depth,
+               void* visual, XID parent_window, bool use_shared_memory);
+  // This is for unittesting only. An object constructed using this constructor
+  // will silently ignore all paints
+  explicit BackingStore(const gfx::Size& size);
+#endif
   ~BackingStore();
 
   const gfx::Size& size() { return size_; }
 
 #if defined(OS_WIN)
   HDC hdc() { return hdc_; }
-#elif defined(OS_POSIX)
+#elif defined(OS_MACOSX)
   skia::PlatformCanvas* canvas() { return &canvas_; }
+#elif defined(OS_LINUX)
+  // Copy from the server-side backing store to the target window
+  //   display: the display of the backing store and target window
+  //   damage: the area to copy
+  //   target: the X id of the target window
+  void ShowRect(const gfx::Rect& damage);
 #endif
 
   // Paints the bitmap from the renderer onto the backing store.
-  bool PaintRect(base::ProcessHandle process,
+  void PaintRect(base::ProcessHandle process,
                  TransportDIB* bitmap,
                  const gfx::Rect& bitmap_rect);
 
   // Scrolls the given rect in the backing store, replacing the given region
   // identified by |bitmap_rect| by the bitmap in the file identified by the
   // given file handle.
   void ScrollRect(base::ProcessHandle process,
                   TransportDIB* bitmap, const gfx::Rect& bitmap_rect,
                   int dx, int dy,
                   const gfx::Rect& clip_rect,
@@ skipping 13 matching lines @@
                    HANDLE section);
 
   // The backing store dc.
   HDC hdc_;
 
   // Handle to the backing store dib.
   HANDLE backing_store_dib_;
 
   // Handle to the original bitmap in the dc.
   HANDLE original_bitmap_;
-#elif defined(OS_POSIX)
+#elif defined(OS_MACOSX)
   skia::PlatformCanvas canvas_;
-#endif  // defined(OS_WIN)
+#elif defined(OS_LINUX)
+  // This is the connection to the X server where this backing store will be
+  // displayed.
+  Display *const display_;
+  // If this is true, then |connection_| is good for MIT-SHM (X shared memory).
+  const bool use_shared_memory_;
+  // The parent window (probably a GtkDrawingArea) for this backing store.
+  const XID parent_window_;
+  // This is a handle to the server side pixmap which is our backing store.
+  XID pixmap_;
+  // This is the RENDER picture pointing at |pixmap_|.
+  XID picture_;
+  // This is a default graphic context, used in XCopyArea
+  void* pixmap_gc_;
+#endif
 
   DISALLOW_COPY_AND_ASSIGN(BackingStore);
 };
 
 // BackingStoreManager ---------------------------------------------------------
 
 // This class manages backing stores in the browsr. Every RenderWidgetHost is
 // associated with a backing store which it requests from this class.  The
 // hosts don't maintain any references to the backing stores.  These backing
 // stores are maintained in a cache which can be trimmed as needed.
 class BackingStoreManager {
  public:
   // Returns a backing store which matches the desired dimensions.
   //
   // backing_store_rect
   //   The desired backing store dimensions.
   // Returns a pointer to the backing store on success, NULL on failure.
   static BackingStore* GetBackingStore(RenderWidgetHost* host,
                                        const gfx::Size& desired_size);
 
   // Returns a backing store which is fully ready for consumption, i.e. the
   // bitmap from the renderer has been copied into the backing store dc, or the
   // bitmap in the backing store dc references the renderer bitmap.
   //
-  // backing_store_rect
+  // backing_store_size
   //   The desired backing store dimensions.
   // process_handle
   //   The renderer process handle.
   // bitmap_section
   //   The bitmap section from the renderer.
   // bitmap_rect
   //   The rect to be painted into the backing store
   // needs_full_paint
   //   Set if we need to send out a request to paint the view
   //   to the renderer.
   static BackingStore* PrepareBackingStore(RenderWidgetHost* host,
-                                           const gfx::Rect& backing_store_rect,
+                                           const gfx::Size& backing_store_size,
                                            base::ProcessHandle process_handle,
                                            TransportDIB* bitmap,
                                            const gfx::Rect& bitmap_rect,
                                            bool* needs_full_paint);
 
   // Returns a matching backing store for the host.
   // Returns NULL if we fail to find one.
   static BackingStore* Lookup(RenderWidgetHost* host);
 
   // Removes the backing store for the host.
   static void RemoveBackingStore(RenderWidgetHost* host);
 
  private:
   // Not intended for instantiation.
   BackingStoreManager() {}
 
   DISALLOW_COPY_AND_ASSIGN(BackingStoreManager);
 };
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_BACKING_STORE_H_