Faster Polysoup

Inspired by NeverWinterNights manner of polysoup, I added optional WalkMeshs. Some dts models are simply too complex to efficiently handle polysoup collisions, especially where a player may attempt to walk. Consider a swinging rope bridge, made up of dozens of rotting boards strung between numerous ropes. Although my testing worked, I found myself getting stuck quite often, as there were simply too many crevices etc to check against.
So, I wrapped the entire structure in a much simpler mesh that still followed the exact shape. Much like the old style Col-1 meshes, except now you're not limited to any silly rules.
A few minor code changes do the job...

First, we won't render any meshes named WalkMesh.
tsShapeInstance.cpp
about line 403. NOTE: I changed the step variable from i to x, to avoid italized viewing of code

for (i=start; i<end; i++)
   {
      smRenderData.currentObjectInstance = &mMeshObjects[x];
      // following line is handy for debugging, to see what part of the shape that it is rendering
		// Opcode change by Fafhrd
      const char *name = mShape->names[mMeshObjects[x].object->nameIndex];
      if (dStrstr(name, "WalkMesh"))
		   continue;
      mMeshObjects[x].render(od,mMaterialList);
   }

Now, upon loading, we'll check if we have a named WalkMesh (and we're using polysoup). If we do,
that's the only mesh we'll prepCollision on. Otherwise, we'll prep the entire model.
tsShapeInstance.cpp
about line 1054, replace entire function

void TSShapeInstance::prepCollision()
{
   // Iterate over all our meshes and call prepCollision on them...
	// Changed by Fafhrd;
	// Loop twice to see if any of the meshes are named WalkMesh. If so, that's the only
	// mesh we will apply opCode too. We're only doing this once at load, so 2 runs is
	// fine.
	bool hasWalkMesh = false;

	for(S32 i=0; i<hShape->meshes.size(); i++)
	{
      if(hShape->meshes[i])
      {
		   S32 nameIndex = hShape->objects[i].nameIndex;
		   const char * meshName = "";
		   if (nameIndex>=0)
		   {
		   	meshName = hShape->getName(nameIndex);
		   	if (dStrstr(meshName, "WalkMesh"))
               hasWalkMesh = true;
		   }
	   }
   }
	for(S32 i=0; i<hShape->meshes.size(); i++)
	{
      if(hShape->meshes[i])
      {
		   S32 nameIndex = hShape->objects[i].nameIndex;
		   const char * meshName = "";
		   if (nameIndex>=0)
		   {
		   	meshName = hShape->getName(nameIndex);
		   	if ((hasWalkMesh && (dStrstr(meshName, "WalkMesh"))) || !hasWalkMesh)
                  hShape->meshes[i]->prepOpcodeCollision();
		   }
	   }
   }
}

Thats it. All done.