History: Coding and Design philosophy

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            == Coding/Design philosophy ==
- A '''quick''' guide to some design issues. What to use when. Please contribute!

=== Class inheritence ===
* [http://www.users.on.net/~edan/misc/ogre_classviz_nodeps.gif Here's a diagram] showing inheritance. Might make some things clearer.
* Although Ogre is a SceneGraph, it's not a strict one. Light, Camera and few things aren't inherited from node. They don't need to be attached to a scenenode (although they can be). This is for convenience and speed.

=== Custom objects ===
- Use '''Movable Object Factories''' when creating reusable custom objects. eg Particle systems, water meshes (eg current water demo would be nice to rewrite as a movable)
* this allows easy creation and management in Ogre
* easy to modularise and reuse
* please wiki any nice custom objects! :)

=== Scene managers ===
- Write a custom scene manager when you require unique scene management.
* eg existing BSP, Octree culling managers
* custom SM's are rarely needed. Octree is a good default for alot of cases.
* multiple scenemanagers can't be run in the same scene (eg terrain and bsp)

=== Scene definition ===
- Or level/scene design
* common solution is the [[dotScene]] xml format (search wiki)
* most modellers can export whole scenes to this format, while also exporting the actual meshes
* example dotScene implementations are in 'ogreAddons' in CVS

=== Main loop/Initialisation ===
* You don't need to use FrameListeners for updating every frame. You can call the render loop manually from a 'normal' while loop if you like.
* You don't need to use ExampleApplication like all the demos use. This either helps or hinders new people. See these examples for alternatives and a clear understanding of what ogre needs to initialise.
[http://www.ogre3d.org/wiki/index.php/MinimalApplication Nice clean example. Uses Framelisteners for render updates]

[http://www.ogre3d.org/phpBB2/viewtopic.php?t=12999&highlight=exampleapp 'Hello World' example]

[http://ogre3d.org/wiki/index.php/Newbie_Tutorial_2 Manual render loop example (windows only)]

[http://code.adaptableit.com/code/solar/ Replacement ExampleApp to inherit new apps from]

[http://www.yake.org A complete framework tying alot of libraries together]

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