michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "SharedDIBWin.h"
michael@0: #include "gfxAlphaRecovery.h"
michael@0: #include "nsMathUtils.h"
michael@0: #include "nsDebug.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace gfx {
michael@0: 
michael@0: static const uint32_t kBytesPerPixel = 4;
michael@0: static const uint32_t kByteAlign = 1 << gfxAlphaRecovery::GoodAlignmentLog2();
michael@0: static const uint32_t kHeaderBytes =
michael@0:   (sizeof(BITMAPV4HEADER) + kByteAlign - 1) & ~(kByteAlign - 1);
michael@0: 
michael@0: SharedDIBWin::SharedDIBWin() :
michael@0:     mSharedHdc(nullptr)
michael@0:   , mSharedBmp(nullptr)
michael@0:   , mOldObj(nullptr)
michael@0: {
michael@0: }
michael@0: 
michael@0: SharedDIBWin::~SharedDIBWin()
michael@0: {
michael@0:   Close();
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: SharedDIBWin::Close()
michael@0: {
michael@0:   if (mSharedHdc && mOldObj)
michael@0:     ::SelectObject(mSharedHdc, mOldObj);
michael@0: 
michael@0:   if (mSharedHdc)
michael@0:     ::DeleteObject(mSharedHdc);
michael@0: 
michael@0:   if (mSharedBmp)
michael@0:     ::DeleteObject(mSharedBmp);
michael@0: 
michael@0:   mSharedHdc = nullptr;
michael@0:   mOldObj = mSharedBmp = nullptr;
michael@0: 
michael@0:   SharedDIB::Close();
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: SharedDIBWin::Create(HDC aHdc, uint32_t aWidth, uint32_t aHeight,
michael@0:                      bool aTransparent)
michael@0: {
michael@0:   Close();
michael@0: 
michael@0:   // create the offscreen shared dib
michael@0:   BITMAPV4HEADER bmih;
michael@0:   uint32_t size = SetupBitmapHeader(aWidth, aHeight, aTransparent, &bmih);
michael@0: 
michael@0:   nsresult rv = SharedDIB::Create(size);
michael@0:   if (NS_FAILED(rv))
michael@0:     return rv;
michael@0: 
michael@0:   if (NS_FAILED(SetupSurface(aHdc, &bmih))) {
michael@0:     Close();
michael@0:     return NS_ERROR_FAILURE;
michael@0:   }
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: SharedDIBWin::Attach(Handle aHandle, uint32_t aWidth, uint32_t aHeight,
michael@0:                      bool aTransparent)
michael@0: {
michael@0:   Close();
michael@0: 
michael@0:   BITMAPV4HEADER bmih;
michael@0:   SetupBitmapHeader(aWidth, aHeight, aTransparent, &bmih);
michael@0: 
michael@0:   nsresult rv = SharedDIB::Attach(aHandle, 0);
michael@0:   if (NS_FAILED(rv))
michael@0:     return rv;
michael@0: 
michael@0:   if (NS_FAILED(SetupSurface(nullptr, &bmih))) {
michael@0:     Close();
michael@0:     return NS_ERROR_FAILURE;
michael@0:   }
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: uint32_t
michael@0: SharedDIBWin::SetupBitmapHeader(uint32_t aWidth, uint32_t aHeight,
michael@0:                                 bool aTransparent, BITMAPV4HEADER *aHeader)
michael@0: {
michael@0:   // D3D cannot handle an offscreen memory that pitch (SysMemPitch) is negative.
michael@0:   // So we create top-to-bottom DIB.
michael@0:   memset((void*)aHeader, 0, sizeof(BITMAPV4HEADER));
michael@0:   aHeader->bV4Size          = sizeof(BITMAPV4HEADER);
michael@0:   aHeader->bV4Width         = aWidth;
michael@0:   aHeader->bV4Height        = -LONG(aHeight); // top-to-buttom DIB
michael@0:   aHeader->bV4Planes        = 1;
michael@0:   aHeader->bV4BitCount      = 32;
michael@0:   aHeader->bV4V4Compression = BI_BITFIELDS;
michael@0:   aHeader->bV4RedMask       = 0x00FF0000;
michael@0:   aHeader->bV4GreenMask     = 0x0000FF00;
michael@0:   aHeader->bV4BlueMask      = 0x000000FF;
michael@0: 
michael@0:   if (aTransparent)
michael@0:     aHeader->bV4AlphaMask     = 0xFF000000;
michael@0: 
michael@0:   return (kHeaderBytes + (-aHeader->bV4Height * aHeader->bV4Width * kBytesPerPixel));
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: SharedDIBWin::SetupSurface(HDC aHdc, BITMAPV4HEADER *aHdr)
michael@0: {
michael@0:   mSharedHdc = ::CreateCompatibleDC(aHdc);
michael@0: 
michael@0:   if (!mSharedHdc)
michael@0:     return NS_ERROR_FAILURE;
michael@0: 
michael@0:   mSharedBmp = ::CreateDIBSection(mSharedHdc,
michael@0:                                   (BITMAPINFO*)aHdr,
michael@0:                                   DIB_RGB_COLORS,
michael@0:                                   &mBitmapBits,
michael@0:                                   mShMem->handle(),
michael@0:                                   kHeaderBytes);
michael@0:   if (!mSharedBmp)
michael@0:     return NS_ERROR_FAILURE;
michael@0: 
michael@0:   mOldObj = SelectObject(mSharedHdc, mSharedBmp);
michael@0: 
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: } // gfx
michael@0: } // mozilla