blob: 8c2ff3bd5bf93e8f003aa356c8f310967bd3cc1e [file] [log] [blame]
// 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/snapshot/snapshot_win.h"
#include "base/win/scoped_gdi_object.h"
#include "base/win/scoped_hdc.h"
#include "base/win/scoped_select_object.h"
#include "ui/gfx/codec/png_codec.h"
#include "ui/gfx/gdi_util.h"
#include "ui/gfx/rect.h"
#include "ui/gfx/size.h"
#include "ui/snapshot/snapshot.h"
namespace {
gfx::Rect GetWindowBounds(HWND window_handle) {
RECT content_rect = {0, 0, 0, 0};
if (window_handle) {
::GetWindowRect(window_handle, &content_rect);
} else {
MONITORINFO monitor_info = {};
monitor_info.cbSize = sizeof(monitor_info);
if (GetMonitorInfo(MonitorFromWindow(NULL, MONITOR_DEFAULTTOPRIMARY),
&monitor_info)) {
content_rect = monitor_info.rcMonitor;
content_rect.right++; // Match what PrintWindow wants.
return gfx::Rect(content_rect.right - content_rect.left,
content_rect.bottom -;
} // namespace
namespace ui {
namespace internal {
bool GrabHwndSnapshot(HWND window_handle,
const gfx::Rect& snapshot_bounds,
std::vector<unsigned char>* png_representation) {
DCHECK(snapshot_bounds.right() <= GetWindowBounds(window_handle).right());
DCHECK(snapshot_bounds.bottom() <= GetWindowBounds(window_handle).bottom());
// Create a memory DC that's compatible with the window.
HDC window_hdc = GetWindowDC(window_handle);
base::win::ScopedCreateDC mem_hdc(CreateCompatibleDC(window_hdc));
unsigned char *bit_ptr = NULL;
base::win::ScopedBitmap bitmap(
reinterpret_cast<void **>(&bit_ptr),
NULL, 0));
base::win::ScopedSelectObject select_bitmap(mem_hdc, bitmap);
// Clear the bitmap to white (so that rounded corners on windows
// show up on a white background, and strangely-shaped windows
// look reasonable). Not capturing an alpha mask saves a
// bit of space.
PatBlt(mem_hdc, 0, 0, snapshot_bounds.width(), snapshot_bounds.height(),
// Grab a copy of the window
// First, see if PrintWindow is defined (it's not in Windows 2000).
typedef BOOL (WINAPI *PrintWindowPointer)(HWND, HDC, UINT);
PrintWindowPointer print_window =
GetProcAddress(GetModuleHandle(L"User32.dll"), "PrintWindow"));
// If PrintWindow is defined, use it. It will work on partially
// obscured windows, and works better for out of process sub-windows.
// Otherwise grab the bits we can get with BitBlt; it's better
// than nothing and will work fine in the average case (window is
// completely on screen). Always BitBlt when grabbing the whole screen.
if (snapshot_bounds.origin() == gfx::Point() && print_window && window_handle)
(*print_window)(window_handle, mem_hdc, 0);
BitBlt(mem_hdc, 0, 0, snapshot_bounds.width(), snapshot_bounds.height(),
window_hdc, snapshot_bounds.x(), snapshot_bounds.y(), SRCCOPY);
// We now have a copy of the window contents in a DIB, so
// encode it into a useful format for posting to the bug report
// server.
gfx::PNGCodec::Encode(bit_ptr, gfx::PNGCodec::FORMAT_BGRA,
snapshot_bounds.width() * 4, true,
ReleaseDC(window_handle, window_hdc);
return true;
} // namespace internal
#if !defined(USE_AURA)
bool GrabViewSnapshot(gfx::NativeView view_handle,
std::vector<unsigned char>* png_representation,
const gfx::Rect& snapshot_bounds) {
return GrabWindowSnapshot(view_handle, png_representation, snapshot_bounds);
bool GrabWindowSnapshot(gfx::NativeWindow window_handle,
std::vector<unsigned char>* png_representation,
const gfx::Rect& snapshot_bounds) {
return internal::GrabHwndSnapshot(window_handle, snapshot_bounds,
#endif // !defined(USE_AURA)
} // namespace ui