.. _world:

World
=====

This chapter will discuss how to load and use the game world in REGoth.

Most world-related operations can be found inside ``src/components/GameWorld.hpp``.

Loading a World
---------------

There are multiple options for loading a world in REGoth:

1. load everything and run the init-script,
2. load everything but don't run the init-script,
3. load only the world-mesh.

We will go through all of them.

As starting point, we will use this application template:

.. code-block:: cpp

   #include "BsFPSCamera.h"
   #include "REGothEngine.hpp"
   #include <Components/BsCCamera.h>
   #include <components/GameWorld.hpp>

   class REGothWorldViewer : public REGoth::REGothEngineDefaultConfig
   {
   public:
     using REGoth::REGothEngineDefaultConfig::REGothEngineDefaultConfig;

     void setupMainCamera() override
     {
       REGoth::REGothEngine::setupMainCamera();

       mMainCamera->SO()->addComponent<bs::FPSCamera>();
     }

     void setupScene() override
     {

     }

   protected:
   };

   int main(int argc, char** argv)
   {
     REGothWorldViewer regoth;

     return REGoth::main(regoth, argc, argv);
   }

This will set up an empty application with a flying FPS-style camera.


Loading everything and run the init-script
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This is the option used to initialize a full game world as you would expect from
playing Gothic. The world-mesh will be there, all supported Vobs are loaded,
decoration, lights, basically everything possible to load from a ZEN.  However
loading only the ZEN will not get you NPCs, some items and other objects you
might expect to find, as those are placed via the worlds init-script.
Therefore, this init-script is executed as well so that those are put into the
world as well.

Inside the applications ``setupScene``-method, go like this:

.. code-block:: cpp

   void setupScene() override
   {
     HGameWorld gameWorld = GameWorld::importZEN("OLDWORLD.ZEN");
     gameWorld->runInitScripts();
   }

This will set you up with everything you need. You can use the handle returned
by `GameWorld::importZEN` to access more world related functionality such as
creating Characters or Items.

.. note::

   You can also chose to not run the init scripts so the world won't be filled with
   Characters. This will also improve loading times.


Load only the world-mesh
~~~~~~~~~~~~~~~~~~~~~~~~

If you really only need the worldmesh, you don't need to initialize the script-VM. You will however lose
support for using ``GameWorld``-component. This is really only useful for development related testing.

To only load the worldmesh from a ZEN, you need to include the following header:

.. code-block:: cpp

   #include <world/internals/ConstructFromZEN.hpp>

And do this inside ``setupScene``:

.. code-block:: cpp

   void setupScene() override
   {
     REGoth::World::loadWorldMeshFromZEN("ADDONWORLD.ZEN");
   }

As you can see, this is using an internal header, so handle it with care.


Using the world
---------------

Once you have successfully initialized a world, you can use the created ``GameWorld``-component
to access it. See ``src/components/GameWorld.hpp`` for the ``GameWorld``-class.

The ``GameWorld``-class allows you to create your own NPCs, Items and also gives
you access to the Waynet among other things.