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en:orx:config:settings_structure:orxbody

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orxBODY structure

Summary

Body

[BodyTemplate]
PartList           = BodyPartTemplate1#BodyPartTemplate2#...
AllowGroundSliding = <bool>
AngularDamping     = <float>
CustomGravity      = <vector>
Dynamic            = <bool>
FixedRotation      = <bool>
HighSpeed          = <bool>
Inertia            = <float>
LinearDamping      = <float>
Mass               = <float>

BodyPart

Sphere

[BodyPartSphereTemplate]
Type        = sphere
Center      = <vector> | full
Radius      = <float> | full
CheckMask   = <16b flags>
SelfFlags   = <16b flags>
Density     = <float>
Friction    = <float>
Restitution = <float>
Solid       = <bool>

Box

[BodyPartBoxTemplate]
Type        = box
TopLeft     = <vector> | full
BottomRight = <vector> | full
CheckMask   = <16b flags>
SelfFlags   = <16b flags>
Density     = <float>
Friction    = <float>
Restitution = <float>
Solid       = <bool>

Mesh (polygon)

[BodyPartMeshTemplate]
Type        = mesh
VertexList  = <vector>#<vector>#...
CheckMask   = <16b flags>
SelfFlags   = <16b flags>
Density     = <float>
Friction    = <float>
Restitution = <float>
Solid       = <bool>

Details

Body

Here's a list of the available properties for an orxBODY structure:

  • PartList: List of all the parts that will compose a body. Up to 8 parts can be defined for a single body. This property needs to be defined if you want it to collide with other bodies.
  • AllowGroundSliding: If set to false on a dynamic object, it will prevent it from sliding on static slopes of more than 45°. This only works with a vertical top-down gravity. By default its value is true.
  • AngularDamping: Damping of angular velocity for this body. By default its value is 0.0, which means no damping.
  • CustomGravity: Defines a gravity vector to use for this body instead of the world's one. By default it doesn't exist, which means world's gravity will be used for this body.
  • Dynamic: Defines if this body should be dynamic or static. If your object is expected to move, this property should be set to true. Static bodies can't collide with other static bodies. By default, its value is false (ie. static).
  • FixedRotation: Defines if your dynamic object is allowed to rotate as a result of collision forces. By default its value is false which means it can rotate freely.
  • HighSpeed: For high velocity objects (like bullets), this property should be set to true to avoid collision errors. However, every object flagged as HighSpeed will cost more when processed by the physics engine. By default its value is false.
  • Inertia: Defines an inertia value for this body. By default its value is 0.0.
  • LinearDamping: Damping of speed (linear velocity) for this body. By default its value is 0.0, which means no damping.
  • Mass: Defines a mass, in kg, for this body. If parts are defined, the mass will be overridden by an automatically calculated value based of parts' sizes and positions.

BodyPart

Common

Here's a list of the available properties for all types of body parts:

  • Type: Defines the type of the body part. Available types are sphere, box and mesh (ie. convex polygon). This property needs to be defined.
  • CheckMask/SelfFlags: Both properties are flags expressed on 16bits. The SelfFlags defines this part identity whereas the CheckMask defines which parts are allowed to collide with it. For a collision to happen between two parts the expressions (Part1.CheckMask & Part2.SelfFlags) and (Part2.CheckMask & Part1.SelfFlags) have both to evaluate to true. NB: Two parts of the same body won't collide whichever CheckMask/SelfFlags they have. 1)
  • Density: Defines the density of this part. Its default value is 0.0, which means it doesn't have any influence on the body's mass.
  • Friction/Restitution: Define the friction and restitution of this part, usually between 0.0 and 1.0. 2) By default both their values are 0.0.
  • Solid: Defines if this part is solid or not. Only solid parts will trigger a reaction on their body when colliding with others. By default its value is false which means the collision info will be signaled through events, but the physics simulation of this body won't be automatically affected by it.
Sphere

Here's a list of the available properties only available to sphere parts:

  • Center: Defines the center of the sphere (in 2D it's a circle, of course) in the parent's space (ie. in object's space). By default its value is full which means the center will match the object's one (ie. the center of its current graphic).
  • Radius: Defines the radius of the sphere (or 2D circle). By default its value is full which means the sphere's radius will match the biggest dimension of the parent object. You can find an example in the spawner tutorial 3).
Box

Here's a list of the available properties only available to box parts:

  • TopLeft/BottomRight: Define the extrema of the box (in 2D it's a rectangle, of course) in the parent's space (ie. in object's space). By default their values are full which means TopLeft and BottomRight will match the full rectangle defined by the parent object's current graphic. You can find an example in the physics tutorial.
Mesh (polygon)

Here's a list of the available properties only available to mesh 4) parts:

  • VertexList: Provides a list of vertex coordinates in parent object's space. The resulting polygon needs to be convex. Up to 8 vertices can be defined and they have to be entered clockwise. You can find an example in the spawner tutorial 5).
1)
Check Box2D wiki for more information on filtering
2)
Check Box2D wiki for more information on friction/restitution
3) , 5)
by looking directly at the config files as they're not covered in the wiki
4)
convex polygon
en/orx/config/settings_structure/orxbody.1278636279.txt.gz · Last modified: 2017/05/30 00:50 (7 years ago) (external edit)