Handle first frame rendering correctly

stepmania/src/arch/MovieTexture/MovieTexture_DShow.cpp

@@ -307,6 +307,17 @@ void MovieTexture_DShow::Create()
 	 * up the texture. */
 	CreateTexture();
 
+	/* Pausing the graph will cause only one frame to be rendered.  Do that, then
+	 * wait for the frame to be rendered, to guarantee that the texture is set
+	 * when this function returns. */
+	Pause();
+
+	CHECKPOINT;
+	SDL_SemWait( pCTR->m_OneFrameDecoded );
+	CHECKPOINT;
+	CheckFrame();
+	CHECKPOINT;
+
 	// Start the graph running
     Play();
 }

stepmania/src/arch/MovieTexture/MovieTexture_DShowHelper.cpp

@@ -17,13 +17,14 @@ CTextureRenderer::CTextureRenderer()
     if( FAILED(CBV_ret) )
         RageException::Throw( hr_ssprintf(CBV_ret, "Could not create texture renderer object!") );
 
-    // Store and ARageef the texture for our use.
 	m_pTexture = NULL;
+
+	m_OneFrameDecoded = SDL_CreateSemaphore(0);
 }
 
 CTextureRenderer::~CTextureRenderer()
 {
-    // Do nothing
+	SDL_DestroySemaphore( m_OneFrameDecoded );
 }
 
 
@@ -88,5 +89,9 @@ HRESULT CTextureRenderer::DoRenderSample( IMediaSample * pSample )
 
 void CTextureRenderer::OnReceiveFirstSample( IMediaSample * pSample )
 {
+	/* If the main thread is in MovieTexture_DShow::Create, kick: */
+	if( SDL_SemValue(m_OneFrameDecoded) == 0 )
+		SDL_SemPost( m_OneFrameDecoded );
+
 	DoRenderSample( pSample );
 }

stepmania/src/arch/MovieTexture/MovieTexture_DShowHelper.h

@@ -35,6 +35,8 @@ public:
 	long GetVidHeight() const { return m_lVidHeight; }
 	void SetRenderTarget( MovieTexture_DShow* pTexture );
 
+	SDL_sem *m_OneFrameDecoded;
+
 protected:
 	// Video width, height, and pitch.
 	long m_lVidWidth, m_lVidHeight, m_lVidPitch;