$collisionmodel

The QC command $collisionmodel is used to embed a static collision mesh in a model, for use in VPhysics calculations. Animated models (including one that will become ragdolls) should use $collisionjoints instead.

Warning:Collision meshes should have extremely few polygons. See Collision mesh for examples.

Note:For collision meshes modeled in XSI ModTool, ensure that none of the edges are marked as hard edges. Hard edges generate errors in the physbox smd.

Tip:Set the Console Variable vcollide_wireframe 1 to view collision meshes in-game.

Syntax

$collisionmodel	<collision mesh SMD>
{
	<options>
}

Options

$mass <float|kilograms>

Manually set the mass of the model, in kilograms.

Tip:By default, the Player can +USE pick up 35KG max. The gravgun can pick up 250KG max. The portal gun can pick up 85KG max.

$automass

Calculate the mass of the model based on the volume of the collision model and the material defined in its prop_data.

$concave

By default, studiomdl will generate a single convex hull by 'shrinkwrapping' any concavities. You can create a concave hull by including multiple convex shapes (potentially overlapping) in your SMD and passing this command.

$maxconvexpieces <int>

By default, the model compiler limits a concave collision model to twenty convex pieces. This command can be used to override the limit if you are creating an Costly collision model.

Note:Introduced with the Orange Box. In the Ep1 engine, run studiomdl with -fullcollide instead.

$masscenter <vector|offset>

Override the center of mass, in local coords.

$inertia <normal>

Inertia scale.

$damping <float>

Linear damping scale.

$rotdamping <float>

Rotational damping scale.

Warning:This affects the pull of gravity on the model and if abused can make it appear to float gently through the air. Valve recommends using "friction" instead.

$drag <normal>

Scales air resistance.

Example

$collisionmodel "tree_deciduous_01a_physbox.smd"
{
	$mass 350.0
	$concave
}

See also

• Collision mesh
• $collisionjoints
• Costly collision model
• VPhysics
• Physics and Ragdolls