[Cel-main] CS + CEL + Dynamic Portals

[Brendon C. <br...@ch...>]

Hi all,

I am trying to get more familiar with CS + CEL and so have been making a
number of modifications to the CEL walktut application. Something I am
currently trying to do is to allow the user to shoot portals at the
walls similar to that done in the games: Portal or Narbacular
Drop.

The idea is simple. There always exist two player located portals in the
game located by something like a "portal gun". I.e. Left mouse button
will perform a hit beam to locate the mesh that is hit and move portal A
to that location, and right mouse button for portal B.

Portals, A and B are always "connected". I.e. Looking and walking
through A takes you to B and vice versa.

I have most of what i want to achieve done, except the actual portals.
My question is, how do i go about creating (in C++) two portals
dynamically (I currently have them as entities but am having trouble
making the mesh contain a portal)?

I currently have two entities ("portal_a" and "portal_b") that have
simple meshes (A box that is very thin, looks like a door) and am able
to move them around the place using the users controls. What i dont seem
to be able to do is to turn a single face of the box into a portal with
a warp.

Basically I wish to use something like the code below to define the mesh
used by the entity for portal_a. Currently i assign from below the mesh:
bmesh_a as the entities mesh. But it is not really working.

After I have this i then realise that whenever i move the entities, I
will also have to get a hold of the iPortal object and adjust the warp
and dest sectors as necessary. I am not quite there yet though.

Is someone able to look at below and give me any tips on how I can
create this mesh with a portal for the front face?

Also given the entity object, and querying the iPcMesh from it, how can
i then get the iPortal object from that iPcMesh instance?

Thanks.
Brendon.

// First create the factory:
fact = engine->CreateMeshFactory ("crystalspace.mesh.object.genmesh",
   "cubeFact");

csRef<iGeneralFactoryState> factstate = scfQueryInterface<
   iGeneralFactoryState> (fact->GetMeshObjectFactory ());

factstate->GenerateBox(csBox3(csVector3(-1.0f, -1.0f, -0.1f),
   csVector3(1.0f, 2.0f, 0.1f)));

factstate->CalculateNormals ();

// Make a plane using the genmesh plug-in.
bmesh_a = engine->CreateMeshWrapper (fact, "bmesh_a", start,
   csVector3 (0, 0, 0));

// Create a portal submesh the same as the front face of the box.
csVector3 vertices[] =
{
   csVector3(-1.0f, -1.0f, 0.1f),
   csVector3(-1.0f,  2.0f, 0.1f),
   csVector3( 1.0f,  2.0f, 0.1f),
   csVector3( 1.0f, -1.0f, 0.1f)
};

iPortal* portal_a = NULL;
csRef<iMeshWrapper> pmesh_a = engine->CreatePortal("portal_a", bmesh_a,
   start, vertices, 4, portal_a);