Use eye->TearDown method to restore glColorMask.

Restore assert in i_system.cpp that was interfering with my debugging.
Restore scoped colorMask-ing in gl_portal.cpp and gl_drawinfo.cpp.

src/gl/scene/gl_drawinfo.cpp

@@ -1014,8 +1014,7 @@ void FDrawInfo::SetupFloodStencil(wallseg * ws)
 	glStencilOp(GL_KEEP, GL_KEEP, GL_INCR);		// increment stencil of valid pixels
 	{
 		// Use revertible color mask, to avoid stomping on anaglyph 3D state
-		// ScopedColorMask colorMask(0, 0, 0, 0); 
+		ScopedColorMask colorMask(0, 0, 0, 0); // glColorMask(0, 0, 0, 0);						// don't write to the graphics buffer
-		glColorMask(0, 0, 0, 0);						// don't write to the graphics buffer
 		gl_RenderState.EnableTexture(false);
 		gl_RenderState.ResetColor();
 		glEnable(GL_DEPTH_TEST);
@@ -1037,7 +1036,7 @@ void FDrawInfo::SetupFloodStencil(wallseg * ws)
 		glStencilFunc(GL_EQUAL, recursion + 1, ~0);		// draw sky into stencil
 		glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);		// this stage doesn't modify the stencil
 
-	} glColorMask(1, 1, 1, 1);						// don't write to the graphics buffer
+	} // glColorMask(1, 1, 1, 1);						// don't write to the graphics buffer
 	gl_RenderState.EnableTexture(true);
 	glDisable(GL_DEPTH_TEST);
 	glDepthMask(false);
@@ -1051,8 +1050,7 @@ void FDrawInfo::ClearFloodStencil(wallseg * ws)
 	gl_RenderState.EnableTexture(false);
 	{
 		// Use revertible color mask, to avoid stomping on anaglyph 3D state
-		// ScopedColorMask colorMask(0, 0, 0, 0); 
+		ScopedColorMask colorMask(0, 0, 0, 0); // glColorMask(0,0,0,0);						// don't write to the graphics buffer
-		glColorMask(0,0,0,0);						// don't write to the graphics buffer
 		gl_RenderState.ResetColor();
 
 		gl_RenderState.Apply();
@@ -1071,7 +1069,7 @@ void FDrawInfo::ClearFloodStencil(wallseg * ws)
 		glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
 		glStencilFunc(GL_EQUAL, recursion, ~0);
 		gl_RenderState.EnableTexture(true);
-	} glColorMask(1, 1, 1, 1);
+	} // glColorMask(1, 1, 1, 1);
 	glEnable(GL_DEPTH_TEST);
 	glDepthMask(true);
 }

src/gl/scene/gl_portal.cpp

@@ -198,7 +198,8 @@ bool GLPortal::Start(bool usestencil, bool doquery)
 		// Create stencil 
 		glStencilFunc(GL_EQUAL,recursion,~0);		// create stencil
 		glStencilOp(GL_KEEP, GL_KEEP, GL_INCR);		// increment stencil of valid pixels
-		glColorMask(0,0,0,0);						// don't write to the graphics buffer
+		{
+			ScopedColorMask colorMask(0, 0, 0, 0); // glColorMask(0,0,0,0);						// don't write to the graphics buffer
 			gl_RenderState.SetEffect(EFF_STENCIL);
 			gl_RenderState.EnableTexture(false);
 			gl_RenderState.ResetColor();
@@ -234,7 +235,7 @@ bool GLPortal::Start(bool usestencil, bool doquery)
 				// set normal drawing mode
 				gl_RenderState.EnableTexture(true);
 				glDepthFunc(GL_LESS);
-			glColorMask(1, 1, 1, 1);
+				// glColorMask(1, 1, 1, 1);
 				gl_RenderState.SetEffect(EFF_NONE);
 				glDepthRange(0, 1);
 
@@ -264,11 +265,12 @@ bool GLPortal::Start(bool usestencil, bool doquery)
 				glStencilFunc(GL_EQUAL, recursion + 1, ~0);		// draw sky into stencil
 				glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);		// this stage doesn't modify the stencil
 				gl_RenderState.EnableTexture(true);
-			glColorMask(1,1,1,1);
+				// glColorMask(1,1,1,1);
 				gl_RenderState.SetEffect(EFF_NONE);
 				glDisable(GL_DEPTH_TEST);
 				glDepthMask(false);							// don't write to Z-buffer!
 			}
+		}
 		recursion++;
 
 
@@ -373,8 +375,7 @@ void GLPortal::End(bool usestencil)
 		GLRenderer->SetupView(viewx, viewy, viewz, viewangle, !!(MirrorFlag & 1), !!(PlaneMirrorFlag & 1));
 
 		{
-			// ScopedColorMask colorMask(0, 0, 0, 0); 
+			ScopedColorMask colorMask(0, 0, 0, 0); // glColorMask(0, 0, 0, 0);						// no graphics
-			glColorMask(0, 0, 0, 0);						// no graphics
 			gl_RenderState.SetEffect(EFF_NONE);
 			gl_RenderState.ResetColor();
 			gl_RenderState.EnableTexture(false);
@@ -403,7 +404,7 @@ void GLPortal::End(bool usestencil)
 
 			gl_RenderState.EnableTexture(true);
 			gl_RenderState.SetEffect(EFF_NONE);
-		}  glColorMask(1, 1, 1, 1);
+		}  // glColorMask(1, 1, 1, 1);
 		recursion--;
 
 		// restore old stencil op.

src/gl/scene/gl_scene.cpp

@@ -840,6 +840,7 @@ sector_t * FGLRenderer::RenderViewpoint (AActor * camera, GL_IRECT * bounds, flo
 
 		ProcessScene(toscreen);
 		EndDrawScene(viewsector);
+		(*eye)->TearDown();
 	}
 	stereo3dMode.TearDown();
 

src/win32/i_system.cpp

@@ -291,7 +291,7 @@ static void I_SelectTimer()
 
 unsigned int I_MSTime()
 {
-	// assert(basetime != 0);
+	assert(basetime != 0);
 	return timeGetTime() - basetime;
 }