3D model

A model being edited in the Softimage Mod Tool.

A model is a collection of points, or vertices, that form a 3D shape known as a mesh. The gaps between the points are usually filled with polygons, and these polygons are usually covered with a material.

Models are used for almost every 3D object in Source that isn't a part of a map's underlying brush geometry. NPCs, physics objects, guns, and sometimes even buildings are all models.

Models are created in external modelling packages that are not part of the Source SDK. Valve recommend the Softimage Mod Tool, but there are other options. The SDK tool studiomdl is used to compile the packages' files into the MDL file format that Source understands.

World vs. View

A Half-Life 2 scene consisting entirely of world models.

World Models

Used by entities which appear in the 3D world. To ensure consistency an entity will normally choose its own world model; the three main exceptions to this are prop_static, prop_physics, and prop_dynamic.

View Models

Hands and weapons that are designed solely to appear as part of a first-person UI. They are typically far more detailed than world models.

Why use a model?

Detail

A model can have many, many times more vertices than a brush. Level of detail allows the detail to be toned down when it is too far away to be appreciated, saving performance.

Skeletal animation

Detailed, efficient, lifelike animation can be achieved with a model. Walking, talking, running, jumping!

Dynamism

Unless specifically made to behave otherwise, a model's position, lighting and animation are all completely dynamic. They can go anywhere and do anything.

Replication

Every instance of a model is guaranteed to look the same, and you can change all of them at once by modifying one small set of files.

See also

• prop_static, prop_dynamic and prop_physics
• Category:World Models
• Half-Life Model Viewer
• Anatomy of a Model
• Model Creation Overview
• Category:Modeling
• MDL (Source Model file format)