gecko-dev/gfx/ipc/SharedDIBWin.cpp

115 строки
3.3 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "SharedDIBWin.h"
#include "gfxAlphaRecovery.h"
#include "nsMathUtils.h"
#include "nsDebug.h"
namespace mozilla {
namespace gfx {
static const uint32_t kByteAlign = 1 << gfxAlphaRecovery::GoodAlignmentLog2();
static const uint32_t kHeaderBytes =
(uint32_t(sizeof(BITMAPV4HEADER)) + kByteAlign - 1) & ~(kByteAlign - 1);
SharedDIBWin::SharedDIBWin()
: mSharedHdc(nullptr), mSharedBmp(nullptr), mOldObj(nullptr) {}
SharedDIBWin::~SharedDIBWin() { Close(); }
nsresult SharedDIBWin::Close() {
if (mSharedHdc && mOldObj) ::SelectObject(mSharedHdc, mOldObj);
if (mSharedHdc) ::DeleteObject(mSharedHdc);
if (mSharedBmp) ::DeleteObject(mSharedBmp);
mSharedHdc = nullptr;
mOldObj = mSharedBmp = nullptr;
SharedDIB::Close();
return NS_OK;
}
nsresult SharedDIBWin::Create(HDC aHdc, uint32_t aWidth, uint32_t aHeight,
bool aTransparent) {
Close();
// create the offscreen shared dib
BITMAPV4HEADER bmih;
uint32_t size = SetupBitmapHeader(aWidth, aHeight, aTransparent, &bmih);
nsresult rv = SharedDIB::Create(size);
if (NS_FAILED(rv)) return rv;
if (NS_FAILED(SetupSurface(aHdc, &bmih))) {
Close();
return NS_ERROR_FAILURE;
}
return NS_OK;
}
nsresult SharedDIBWin::Attach(Handle aHandle, uint32_t aWidth, uint32_t aHeight,
bool aTransparent) {
Close();
BITMAPV4HEADER bmih;
SetupBitmapHeader(aWidth, aHeight, aTransparent, &bmih);
nsresult rv = SharedDIB::Attach(aHandle, 0);
if (NS_FAILED(rv)) return rv;
if (NS_FAILED(SetupSurface(nullptr, &bmih))) {
Close();
return NS_ERROR_FAILURE;
}
return NS_OK;
}
uint32_t SharedDIBWin::SetupBitmapHeader(uint32_t aWidth, uint32_t aHeight,
bool aTransparent,
BITMAPV4HEADER* aHeader) {
// D3D cannot handle an offscreen memory that pitch (SysMemPitch) is negative.
// So we create top-to-bottom DIB.
memset((void*)aHeader, 0, sizeof(BITMAPV4HEADER));
aHeader->bV4Size = sizeof(BITMAPV4HEADER);
aHeader->bV4Width = aWidth;
aHeader->bV4Height = -LONG(aHeight); // top-to-buttom DIB
aHeader->bV4Planes = 1;
aHeader->bV4BitCount = 32;
aHeader->bV4V4Compression = BI_BITFIELDS;
aHeader->bV4RedMask = 0x00FF0000;
aHeader->bV4GreenMask = 0x0000FF00;
aHeader->bV4BlueMask = 0x000000FF;
if (aTransparent) aHeader->bV4AlphaMask = 0xFF000000;
return (kHeaderBytes +
(-aHeader->bV4Height * aHeader->bV4Width * kBytesPerPixel));
}
nsresult SharedDIBWin::SetupSurface(HDC aHdc, BITMAPV4HEADER* aHdr) {
mSharedHdc = ::CreateCompatibleDC(aHdc);
if (!mSharedHdc) return NS_ERROR_FAILURE;
mSharedBmp =
::CreateDIBSection(mSharedHdc, (BITMAPINFO*)aHdr, DIB_RGB_COLORS,
&mBitmapBits, mShMem->GetHandle(), kHeaderBytes);
if (!mSharedBmp) return NS_ERROR_FAILURE;
mOldObj = SelectObject(mSharedHdc, mSharedBmp);
return NS_OK;
}
} // namespace gfx
} // namespace mozilla