The Osirion Project - MODELS

Creating 3D models for The Osirion Project

Introduction

	The engine supports loading of Quake 2 .map files with custom osirion
	entities. While it might look like a weird choice for a file format
	it has been a well-considered pragmatic choice. 

	First of all, creating commercial grade graphics has never been 
	my goal. Polished high-quality models demand a lot of time, 
	skill and effort.

	The same goes for 3D modelling packages like Blender or 3D Studio Max.
	They are capable of producing awesome results, but the learning curve
	is quite steep and the number of availble 3D artists is rather limited.

	GtkRadiant on the other hand has been my personal tool for some time
	now. For an experienced mapper, creating a LEGO-style model is only
	a matter of hours and without the usual technical difficulties of 
	creating a map for shoot'em'up.

	Creating game content is usually a chicken-and-egg in a small game
	project. I hope to solve it by choosing a widely available and
	easy to master format.

	The rest of this document contains information specific to creating
	models for the Osirion Project. Even if you can handle GtkRadiant,
	it is still worth a read.

Creating models with GtkRadiant

	All the models for the game were created with GtkRadiant 1.5.0,
	in theory any editor capable of exporting Quake 2 .map files could
	be used. Support for files for GtkRadiant 1.5.0 are included in the 
	data distribution. Refer to the file INSTALL on where to find them 
	and how to install them. No map compiler is necessary, the engine 
	reads the .map files directly.

	If you are using a linux-based operating system, you can also use 
	the GtkRadiant distribution from http://ingar.soliter.org.
	Note that it does not include the Osirion support files by default.

	This document will not explain how to use the editor. Consult google
	for numerous tutorials on this subject. Any basic brush-creating 
	techniques for any Quake-engine based game can be used.

	The main difference with other games is that you are not creating
	a map for a 3d-shoot'em'up but, obviously, an object that has to be
	loaded into a space game.

	Because there is no map compile involved, and the engine is fundamentally
	different, some points should be take under consideration.

Brushes and sizes

	The engine supports brushes only. Patches will be ignored. A large number
	of complex brushes is supported, but I advise not to go below grid size 1.
	As with any engine it is still possible to create brushwork that gets
	messed up.

	When the model is loaded, the bounding box is calculated. The center 
	of the model will be placed at the center of the bounding box.

	The limits of map coordinates are placed on +/-16384 map units. Placing
	brushes outside these bounds will have unpredictable results. The map 
	will be scaled down to make 1024 map units correspond to 1 game unit.

	The front of a model points along the positive X-axis, the positive
	Z-axis is up, the positive Y-axis is left.

Caulk

	Any brush face that has the common/caulk texture will be ignored on load.

Clip
	Any brush face that has the common/clip texture will be ignored on load.
	Clip is reserved for future use.

Detail brushes

	As with other engines, Osirion supports the use of detail brushes, but
	witha  twist: detail brushes will only be rendered if the model 
	is close enough to the camera. When it is further away, only structural 
	brushes will be rendered.

	This means that any objects that could only been seen from close by
	should be made from detail brushes.

	This has one improtant implication: if you show the structural brushes
	only (with the CTRL+D filter in Gtkradiant) there should be no obvious
	gaps of caulk that were previously hidden behind detail brushes.

Textures
	
	The engine supports no textures. Any real texturing information 
	is ignored.

	The textures in the directory /textures/colors can be used by 
	the editor. The engine translates these textures into RGB colors 
	when the model is loaded. Unknown textures will be colored hot pink.

	You can also use two special textures from the /textures/common
	directory: as explained above, faces with the common/caulk texture
	will be ignored on load. The use of common/clip is reserved for
	future use. At the moment they will be ignored as well.

	At the time of writing, texture names are hardcoded in src/core/model.cc
	
Entities

	Add an info_engine entity to add an engine exhaust to a ship model.
	An engine always points to the rear (negative Z-axis). Engines
	will only be rendered if the model is close enough.

Lights

	Support for light entities is very basic, the end result is far 
	from pleasing for the eye. They do have their use, since lights	
	are only rendered if the model is close enough. The engine does support
	coloured lights (with the 'K' menu in GtkRadiant).

	The strobe option (spawnflag 1) will create a flashing light.