Using PrimBuild

Ok, pardon me for posting this if it's already been answered, but I've read the documentation, forums, searched the resources and haven't really found anything that shows a simple example of how to use PrimBuild. I thought I had it, but I'm doing something wrong.

I started with a simple code change to draw the mission area. I modified the mission area to match the spawn point of the camera so I'd know approximately where it would show up.

Then, in game.cpp/GameRenderWorld() I added made the following change.

// Need to consoldate to one clear call // glClear(GL_DEPTH_BUFFER_BIT);
   GFX->setCullMode( GFXCullNone );//glDisable(GL_CULL_FACE);

   gClientSceneGraph->renderScene();

   [b]GameRenderMissionArea();[/b]

   GFX->setZEnable( false ); //glDisable(GL_DEPTH_TEST);
   collisionTest.render();

Then I created the function GameRenderMissionArea() and added the appropriate includes at the top of the file.

void GameRenderMissionArea()
{
   static RectI lastMissionArea;
   static GFXVertexBuffer* pVertexBuffer = NULL;
   static F32 height = 0.0;
   static F32 depth = 0.0;
   static U32 numPrims = 0;

   // Initialize the last mission area so we have known values.
   if (pVertexBuffer == NULL)
   {
      lastMissionArea.set(0, 0, 0, 0);
   }

   if (MissionArea::smMissionArea != lastMissionArea)
   {
      lastMissionArea = MissionArea::smMissionArea;
      height = 300;  // MissionArea::smflightCeiling;
      depth = 50.0;   // Override based on loweest terrain point?

      if (pVertexBuffer)
      {
         // Is this the correct way to delete a vertext buffer?
         delete pVertexBuffer;
         pVertexBuffer = NULL;
      }

      // Create or re-create the primitive
      PrimBuild::beginToBuffer(GFXTriangleList, 3);

      // For now, lets just draw single solid triangle.  
      // When we draw more, switch to drawing GFXTriangleStrip

      PrimBuild::color4f(1.0, 1.0, 1.0, 1.0);

      // Side 1, Tri 1
      PrimBuild::vertex3f(lastMissionArea.point.x, lastMissionArea.point.y, depth);
      PrimBuild::vertex3f(lastMissionArea.point.x, lastMissionArea.point.y + lastMissionArea.extent.y, depth);
      PrimBuild::vertex3f(lastMissionArea.point.x, lastMissionArea.point.y, height);
      
      pVertexBuffer = PrimBuild::endToBuffer(numPrims);
   }

   if (pVertexBuffer)
   {
      // Render here.
      //pVertexBuffer->prepare();
      GFX->setVertexBuffer(pVertexBuffer);
      //GFX->drawPrimitives();
      GFX->drawPrimitive(GFXTriangleList, 0, numPrims);
   }

   // TODO: Fix this!
   // ACK! pVertexBuffer is leaked, but only one per process.
   // Would GFXBufferHandle<> or whatever help out?
}

I've tried using GFXTriangleStrip, I've tried drawPrimitive() vs drawPrimitives() but no luck. Some different variations have produced an odd looking shape and others have produced a cube of sorts.

I'm missing something, and maybe it's just because I bought TSE yesterday and I've only gotten a couple hours of sleep because I've been playing with it. :p New toys, ya know?