在網(wǎng)頁中只需要加入以下代碼
<object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,29,0" width="600" height="60">
<param name="movie" value="test.swf">
<param name="quality" value="high">
<param name="wmode" value="transparent">
<embed src="***.swf" quality="high" pluginspage="http://www.macromedia.com/go/getflashplayer" type="application/x-shockwave-flash" width="600" height="60"></embed>
</object>
就可以實(shí)現(xiàn) Flash 背景透明
在VC中要實(shí)現(xiàn) Flash 背影透明播放，Google了一下找到一個(gè) Demo
原文URL：
http://www.codeproject.com/KB/COM/flashcontrol.aspx需要自己實(shí)現(xiàn)一個(gè)OLE容器，以前很少接觸COM，現(xiàn)在要實(shí)現(xiàn)的是一個(gè)OLE容器，先汗一下！！！！
想到一個(gè)問題：自己實(shí)現(xiàn)一個(gè)OLE容器跟使用直接使用FlashOcx 控件有何不同？
-- 未解決
Part 1
實(shí)現(xiàn)一個(gè)ActiveX對(duì)象的OLE容器需要繼承幾個(gè)接口
IOleClientSite
IOleInPlaceSiteWindowless
IOleInPlaceFrame
IStorage
(具體做什么，需要找資料惡補(bǔ)一下~~~~ ActiveX, OLE容器……)
在DEMO里實(shí)現(xiàn)了一個(gè)OLE容器類叫 COleContainerWnd
template<CLASS T>
class COleContainerWnd : virtual public IOleClientSite,
virtual public IOleInPlaceSiteWindowless,
virtual public IOleInPlaceFrame,
virtual public IStorage
是個(gè)模板類，T是留給 ActiveX 的接口
Part 2
把 flash.ocx 引進(jìn)來，因?yàn)槔锩姘薋lash播放器的相關(guān)接口定義，它就是我們要放到容器里的 ActiveX 對(duì)象了
#import "flash.ocx" named_guids
Part 3
CFlashWnd派生類
class CFlashWnd: public COleContainerWnd<ShockwaveFlashObjects::IShockwaveFlash>,
public ShockwaveFlashObjects::_IShockwaveFlashEvents,
public ShockwaveFlashObjects::IServiceProvider
再汗一下，CFlashWnd 是個(gè)容器，還要實(shí)現(xiàn) public ShockwaveFlashObjects::IServiceProvider 接口作甚？
至于要繼承 ShockwaveFlashObjects::_IShockwaveFlashEvents 接口的目的是為了接收 Flash 動(dòng)畫發(fā)過來的 fscommand() 事件，在 Flash的AS（動(dòng)作腳本）中調(diào)用 FsCommand()，就會(huì)
觸發(fā)這個(gè)事件了
(這是一個(gè)精通 Flash 的同學(xué)告訴我的！！)
CFlashWnd 對(duì)象的創(chuàng)建
g_flashWnd = new CFlashWnd;
g_flashWnd->Create(ShockwaveFlashObjects::CLSID_ShockwaveFlash,
WS_EX_LAYERED, WS_POPUP | WS_VISIBLE | WS_CLIPSIBLINGS,
g_hWnd, g_hInst);
Create() 函數(shù)的第一個(gè)參數(shù)：Flash 播放對(duì)象的ClassID
Create() 函數(shù)的第二個(gè)參數(shù)：窗體的擴(kuò)展風(fēng)格 WS_EX_LAYERED ，據(jù)說加了這個(gè)風(fēng)格才能實(shí)現(xiàn)透明 Flash ，為啥？
……
Part 4
CFlashWnd::Create() 的內(nèi)幕
注冊(cè)了窗口類，然后就 CreateWindows 了
值得注意的是
OleCreate() 函數(shù)用來創(chuàng)建一個(gè) IOleObject 對(duì)象的實(shí)例，需要 把 Ole 容器 的 IOleClientSite 和 IStorage 作為參數(shù)傳給它
hr = OleCreate(m_CLSID, IID_IOleObject, OLERENDER_DRAW,
0, (IOleClientSite *)this, (IStorage *)this, (void **)&m_lpO);
hr = OleSetContainedObject(m_lpO, TRUE);
OleSetContainedObject () 函數(shù)通知 IOleObject 對(duì)象跟它說，你已經(jīng)被嵌到 OLE 容器里了
hr = m_lpO->QueryInterface(__uuidof(T), (void **)&m_lpControl);
然后用 IOleObject 的 QueryInterface 獲取 IShockwaveFlash 接口（那個(gè) T, 就是 ShockwaveFlashObjects::IShockwaveFlash 了）
hr = m_lpO->QueryInterface(IID_IViewObjectEx, (void **)&m_lpViewObjectEx);
同樣的方法，也得到了 IViewObjectEx 的接口
IViewObjectEx 用來干嘛的？？
要?jiǎng)?chuàng)建一個(gè)無窗口的控件，OLE容器需要 IOleInPlaceObjectWindowless 接口來分派消息給對(duì)象, 因?yàn)?對(duì)象本身沒有自己所屬的窗體
另外，IOleInPlaceObject 接口需要重出那個(gè)對(duì)象
hr = m_lpO->DoVerb(OLEIVERB_SHOW, NULL, (IOleClientSite *)this, 0, NULL, NULL);
IOleObject::DoVerb() 用來顯示對(duì)象和將對(duì)象置為運(yùn)行的狀態(tài)
這樣，F(xiàn)lash 播放對(duì)象就建好了.....
Part 5.
透明窗體的重畫
1、創(chuàng)建窗體時(shí)加上 WS_EX_LAYERED 屬性
2、用 CreateDIBSection() 創(chuàng)建一個(gè) 32位的DIB塊, 然后把它 Select 到 DC 里面, It will be an offscreen plain to render window contents to. (這句不知如何譯....)
3、描繪窗體的內(nèi)容, preserving the alpha channel. (同上..)
4、調(diào)用 UpdateLayeredWindow() 函數(shù)重畫窗體
描繪 Flash 播放的內(nèi)容，用 OleDraw() 函數(shù), 在 IViewObject::Draw() 中調(diào)用
hr = OleDraw(lpV, DVASPECT_TRANSPARENT, hdcDraw, &rTotal);
lpV – IViewObject interface of flash player control
hdcDraw – offscreen plain
rTotal – client rectangle of the container window
DVASPECT_TRANSPARENT drawing aspect tells the object to draw it's content using alpha blending.
DVASPECT_TRANSPARENT drawing aspect tells the object to draw it's content using alpha blending.
While implementing this, I have met a serious bug in Flash Player Control 8. This bug is only in this version. Players 7 and 9 are free of it. The bug is in the way Flash Control fills the alpha channel of a 32 bit device context. If at least 1 of 255 alpha values is applied to pixel, the colors are mixed correctly, but the resulting alpha channel is set to 255, even if it was initially zero. This makes it impossible to create semitransparent windows. So I had to develop a solution to fix this bug. The solution is quite simple:
These equations are used by Flash Player Control for alpha blending:
R' = Rdst * (1 – alpha) + Rsrc * alpha
G' = Gdst * (1 – alpha) + Gsrc * alpha
B' = Bdst * (1 – alpha) + Bsrc * alpha
If I draw the contents of Flash onto black surface I get
R'black = Rsrc * alpha
G'black = Gsrc * alpha
B'black = Bsrc * alpha
If I draw the contents of Flash onto white surface I get
R'white = 255 * (1 – alpha) + Rsrc * alpha
G'white = 255 * (1 – alpha) + Rsrc * alpha
B'white = 255 * (1 – alpha) + Rsrc * alpha
Here is the system of equations:
R'black = Rsrc * alpha
R'white = 255 * (1 – alpha) + Rsrc * alpha
where alpha and Rsrc are unknown. After solving it you will get:
(255-Alpha) = R'white – R'black
Alpha = 255 – (R'white – R'black) So, the solution is found. Now, we can draw contents of flash player twice and then correct the corrupted alpha channel.
Part 6. Events
Flash Player 對(duì)象的事件是用IDispatch來處理的，在創(chuàng)建后得到一個(gè) IConnectionPointContainer 去獲取 DIID__IShockwaveFlashEvents 的 連接點(diǎn)(connection point)
hr = m_lpControl->QueryInterface(IID_IConnectionPointContainer,
(void**)&m_lpConCont);
if (FAILED(hr))
return FALSE;
hr = m_lpConCont->FindConnectionPoint(
ShockwaveFlashObjects::DIID__IShockwaveFlashEvents, &m_lpConPoint);
if (FAILED(hr))
return FALSE;
hr = m_lpConPoint->Advise(
(ShockwaveFlashObjects::_IShockwaveFlashEvents*)this,
&m_dwConPointID);
if (FAILED(hr))
return FALSE;
Part 7. DirectDraw
為了提交重畫的性能，所以使用 DirectDraw 接口
Flash對(duì)象通過 ShockwaveFlashObjects::IServiceProvider::raw_RemoteQueryService 這個(gè)接口來訪問它
(需要找一下 FlashObject 接口的文檔了解一下)
（眼睛睜不開，需要先睡一會(huì)………………）