added directx and divx checkers and divx auto installer

stepmania/src/RageMovieTexture.cpp

@@ -326,7 +326,47 @@ HRESULT RageMovieTexture::InitDShowTextureRenderer()
 
     // Add the source filter
     if( FAILED( hr = m_pGB->AddSourceFilter( wFileName, L"SOURCE", &pFSrc ) ) )
+	{
+		int iRetVal = MessageBox( NULL, "Could not locate the DivX video codec. \n\
+DivX is required to play the animations in this game and must \n\
+be installed before running the application.\n\n\
+If you'd like, we can install the DivX codec version 3.11 \n\
+automatically for you.  Would you like to do this?", "Error - DivX missing", MB_YESNO|MB_ICONSTOP );
+		if( iRetVal == IDYES )
+		{
+			STARTUPINFO si;
+			ZeroMemory( &si, sizeof(si) );
+			si.cb = sizeof(si);
+			PROCESS_INFORMATION pi;
+
+
+			CreateProcess(
+				NULL,
+				"divx/Register_DivX.exe",  // pointer to command line string
+				NULL,  // process security attributes
+				NULL,   // thread security attributes
+				FALSE,  // handle inheritance flag
+				0, // creation flags
+				NULL,  // pointer to new environment block
+				"divx",   // pointer to current directory name
+				&si,  // pointer to STARTUPINFO
+				&pi  // pointer to PROCESS_INFORMATION
+			);
+
+		}
+		else
+		{
+			int iRetVal = MessageBox( NULL, "We're sorry, but you must install DivX before using this application.\n\
+Would you like to visit www.divx.com for more information on DivX codec?", "Sorry", MB_YESNO|MB_ICONSTOP );
+			if( iRetVal == IDYES )
+			{
+				GotoURL("http://www.divx.com");
+			}
+		}
+		exit(1);
+		// if this fails, it's probably because the user doesn't have DivX installed
         RageErrorHr( "Could not create source filter to graph!", hr );
+	}
     
     // Find the source's output and the renderer's input
     if( FAILED( hr = pFTR->FindPin( L"In", &pFTRPinIn ) ) )