diff --git a/stepmania/src/Actor.cpp b/stepmania/src/Actor.cpp
index d4ff7f5ba6..33baf6cd96 100644
--- a/stepmania/src/Actor.cpp
+++ b/stepmania/src/Actor.cpp
@@ -76,6 +76,7 @@ void Actor::Reset()
 
 	m_bTextureWrapping = false;
 	m_BlendMode = BLEND_NORMAL;
+	m_bZBias = false;
 	m_bClearZBuffer = false;
 	m_ZTestMode = ZTEST_OFF;
 	m_bZWrite = false;
@@ -385,6 +386,11 @@ void Actor::SetGlobalRenderStates()
 	DISPLAY->SetBlendMode( m_BlendMode );
 	DISPLAY->SetZWrite( m_bZWrite );
 	DISPLAY->SetZTestMode( m_ZTestMode );
+	
+	// BLEND_NO_EFFECT is used to draw masks to the Z-buffer, which always wants
+	// Z-bias enabled.
+	DISPLAY->SetZBias( m_bZBias || m_BlendMode == BLEND_NO_EFFECT );
+
 	if( m_bClearZBuffer )
 		DISPLAY->ClearZBuffer();
 	DISPLAY->SetCullMode( m_CullMode );
diff --git a/stepmania/src/Actor.h b/stepmania/src/Actor.h
index d686c964e2..8ba73fd1ce 100644
--- a/stepmania/src/Actor.h
+++ b/stepmania/src/Actor.h
@@ -342,6 +342,7 @@ public:
 	virtual void SetZTestMode( ZTestMode mode ) { m_ZTestMode = mode; } 
 	void SetZTestModeString( const CString &s );	// convenience
 	virtual void SetZWrite( bool b ) 			{ m_bZWrite = b; } 
+	void SetZBias( bool b )						{ m_bZBias = b; }
 	virtual void SetCullMode( CullMode mode ) 	{ m_CullMode = mode; } 
 	void SetCullModeString( const CString &s );	// convenience
 
@@ -463,6 +464,7 @@ protected:
 	bool		m_bClearZBuffer;
 	ZTestMode	m_ZTestMode;
 	bool		m_bZWrite;
+	bool		m_bZBias; // if true, always wins z-test against a coplanar actor
 	CullMode	m_CullMode;
 
 	//
@@ -576,6 +578,7 @@ public:
 	static int ztest( T* p, lua_State *L )				{ p->SetZTestMode((!!IArg(1))?ZTEST_WRITE_ON_PASS:ZTEST_OFF); return 0; }
 	static int ztestmode( T* p, lua_State *L )			{ p->SetZTestModeString(SArg(1)); return 0; }
 	static int zwrite( T* p, lua_State *L )				{ p->SetZWrite(!!IArg(1)); return 0; }
+	static int zbias( T* p, lua_State *L )				{ p->SetZBias(!!IArg(1)); return 0; }
 	static int clearzbuffer( T* p, lua_State *L )		{ p->SetClearZBuffer(!!IArg(1)); return 0; }
 	static int backfacecull( T* p, lua_State *L )		{ p->SetCullMode((!!IArg(1)) ? CULL_BACK : CULL_NONE); return 0; }
 	static int cullmode( T* p, lua_State *L )			{ p->SetCullModeString(SArg(1)); return 0; }
@@ -694,6 +697,7 @@ public:
 		ADD_METHOD( ztest )
 		ADD_METHOD( ztestmode )
 		ADD_METHOD( zwrite )
+		ADD_METHOD( zbias )
 		ADD_METHOD( clearzbuffer )
 		ADD_METHOD( backfacecull )
 		ADD_METHOD( cullmode )
diff --git a/stepmania/src/RageDisplay.h b/stepmania/src/RageDisplay.h
index 0dc05b27cd..3e340c3f7c 100644
--- a/stepmania/src/RageDisplay.h
+++ b/stepmania/src/RageDisplay.h
@@ -172,6 +172,7 @@ public:
 	virtual bool IsZWriteEnabled() const = 0;
 	virtual void SetZWrite( bool b ) = 0;
 	virtual void SetZTestMode( ZTestMode mode ) = 0;
+	virtual void SetZBias( bool b ) = 0;
 	virtual void ClearZBuffer() = 0;
 
 	virtual void SetCullMode( CullMode mode ) = 0;
diff --git a/stepmania/src/RageDisplay_D3D.cpp b/stepmania/src/RageDisplay_D3D.cpp
index 1ecfc908ac..5282d0e76a 100644
--- a/stepmania/src/RageDisplay_D3D.cpp
+++ b/stepmania/src/RageDisplay_D3D.cpp
@@ -1035,7 +1035,6 @@ void RageDisplay_D3D::SetTextureFiltering( bool b )
 void RageDisplay_D3D::SetBlendMode( BlendMode mode )
 {
 	g_pd3dDevice->SetRenderState( D3DRS_ALPHABLENDENABLE, TRUE );
-	g_pd3dDevice->SetRenderState( D3DRS_ZBIAS, 0 );
 	switch( mode )
 	{
 	case BLEND_NORMAL:
@@ -1049,11 +1048,6 @@ void RageDisplay_D3D::SetBlendMode( BlendMode mode )
 	case BLEND_NO_EFFECT:
 		g_pd3dDevice->SetRenderState( D3DRS_SRCBLEND,  D3DBLEND_ZERO );
 		g_pd3dDevice->SetRenderState( D3DRS_DESTBLEND, D3DBLEND_ONE );
-
-		/* This is almost exclusively used to draw masks to the Z-buffer.  Make sure
-		 * masks always win the depth test when drawn at the same position. */
-		g_pd3dDevice->SetRenderState( D3DRS_ZBIAS, 30 );	// this bias is bigger than it needs to be to handle the coplanar case
-
 		break;
 	default:
 		ASSERT(0);
@@ -1067,6 +1061,15 @@ bool RageDisplay_D3D::IsZWriteEnabled() const
 	return b!=0;
 }
 
+void RageDisplay_D3D::SetZBias( bool b )
+{
+	if( b )
+		g_pd3dDevice->SetRenderState( D3DRS_ZBIAS, 30 );
+	else
+		g_pd3dDevice->SetRenderState( D3DRS_ZBIAS, 0 );
+}
+
+
 bool RageDisplay_D3D::IsZTestEnabled() const
 {
 	DWORD b;
diff --git a/stepmania/src/RageDisplay_D3D.h b/stepmania/src/RageDisplay_D3D.h
index 5ec776b42d..5c72dca4c3 100644
--- a/stepmania/src/RageDisplay_D3D.h
+++ b/stepmania/src/RageDisplay_D3D.h
@@ -41,6 +41,7 @@ public:
 	bool IsZWriteEnabled() const;
 	bool IsZTestEnabled() const;
 	void SetZWrite( bool b );
+	void SetZBias( bool b );
 	void SetZTestMode( ZTestMode mode );
 	void ClearZBuffer();
 	void SetCullMode( CullMode mode );
diff --git a/stepmania/src/RageDisplay_Null.h b/stepmania/src/RageDisplay_Null.h
index c9e6e02113..1e4238ea40 100644
--- a/stepmania/src/RageDisplay_Null.h
+++ b/stepmania/src/RageDisplay_Null.h
@@ -39,6 +39,7 @@ public:
 	bool IsZWriteEnabled() const { return false; }
 	bool IsZTestEnabled() const { return false; }
 	void SetZWrite( bool b ) { }
+	void SetZBias( bool b ) { }
 	void SetZTestMode( ZTestMode mode ) { }
 	void ClearZBuffer() { }
 	void SetCullMode( CullMode mode ) { }
diff --git a/stepmania/src/RageDisplay_OGL.cpp b/stepmania/src/RageDisplay_OGL.cpp
index 7d19afad28..4131ac24ba 100644
--- a/stepmania/src/RageDisplay_OGL.cpp
+++ b/stepmania/src/RageDisplay_OGL.cpp
@@ -349,6 +349,7 @@ RageDisplay_OGL::RageDisplay_OGL()
 	InitStringMap();
 
 	wind = NULL;
+	g_bTextureMatrixShader = NULL;
 }
 
 CString GetInfoLog( GLhandleARB h )
@@ -1472,7 +1473,6 @@ void RageDisplay_OGL::SetBlendMode( BlendMode mode )
 {
 	glEnable(GL_BLEND);
 
-	glDepthRange( 0.05, 1.0 );
 	switch( mode )
 	{
 	case BLEND_NORMAL:
@@ -1484,10 +1484,6 @@ void RageDisplay_OGL::SetBlendMode( BlendMode mode )
 	case BLEND_NO_EFFECT:
 		/* XXX: Would it be faster and have the same effect to say glDisable(GL_COLOR_WRITEMASK)? */
 		glBlendFunc( GL_ZERO, GL_ONE );
-
-		/* This is almost exclusively used to draw masks to the Z-buffer.  Make sure
-		 * masks always win the depth test when drawn at the same position. */
-		glDepthRange( 0.0, 0.95 );	// this bias is bigger than it needs to be to handle the coplanar case
 		break;
 	default:
 		ASSERT(0);
@@ -1521,6 +1517,14 @@ void RageDisplay_OGL::SetZWrite( bool b )
 	glDepthMask( b );
 }
 
+void RageDisplay_OGL::SetZBias( bool b )
+{
+	if( b )
+		glDepthRange( 0.0, 0.95 );
+	else 
+		glDepthRange( 0.05, 1.0 );
+}
+
 void RageDisplay_OGL::SetZTestMode( ZTestMode mode )
 {
 	glEnable( GL_DEPTH_TEST );
diff --git a/stepmania/src/RageDisplay_OGL.h b/stepmania/src/RageDisplay_OGL.h
index b9c6044c5b..b3f3e56bb8 100644
--- a/stepmania/src/RageDisplay_OGL.h
+++ b/stepmania/src/RageDisplay_OGL.h
@@ -42,6 +42,7 @@ public:
 	bool IsZWriteEnabled() const;
 	bool IsZTestEnabled() const;
 	void SetZWrite( bool b );
+	void SetZBias( bool b );
 	void SetZTestMode( ZTestMode mode );
 	void ClearZBuffer();
 	void SetCullMode( CullMode mode );