Box2D b2Shape documentation

b2d.shape.definition

b2d.shape.definition = { type:b2d.shape.SHAPE_TYPE, radius:number, center?:vector3 } | { type:b2d.shape.SHAPE_TYPE, radius:number, center1:vector3, center2:vector3 } | { type:b2d.shape.SHAPE_TYPE, v1:vector3, v2:vector3, v0?:vector3, v3?:vector3 } | { type:b2d.shape.SHAPE_TYPE, hx:number, hy:number, center?:vector3, angle?:number } | { type:b2d.shape.SHAPE_TYPE, vertices:vector3[], loop?:boolean, prev_vertex?:vector3, next_vertex?:vector3 }

A reusable table describing Box2D shape geometry. It is accepted by shape creation, query, cast, and update functions, and is returned by b2d.shape.get_shape or b2d.fixture.get_shape. Available fields depend on type:

• Circle: radius and optional center.
• Capsule: radius, center1, and center2.
• Edge or segment: v1, v2, and optional ghost vertices v0 and v3.
• Box: half-extents hx and hy, with optional center and angle in radians.
• Polygon: vertices.
• Chain: vertices, with optional loop and ghost-vertex fields.

EXAMPLES

local circle = {
    type = b2d.shape.SHAPE_TYPE_CIRCLE,
    radius = 16,
    center = vmath.vector3(0, 8, 0),
}

local box = {
    type = b2d.shape.SHAPE_TYPE_BOX,
    hx = 32,
    hy = 8,
    angle = math.rad(15),
}

b2Shape

b2Shape = userdata

An opaque handle to one collision shape attached to a b2Body. Obtain shape handles from b2d.body.get_shapes or when creating shapes, then use the functions in b2d.shape to inspect or modify them. A shape is owned by its body and its handle becomes invalid when the shape or body is destroyed.

EXAMPLES

local body = b2d.get_body("#collisionobject")
local shapes = b2d.body.get_shapes(body)
local shape = shapes[1].shape_id
pprint(b2d.shape.get_shape(shape))

b2d.shape.SHAPE_TYPE

b2d.shape.SHAPE_TYPE: integer

Box2D shape types.

VALUES

b2d.shape.are_contact_events_enabled()

b2d.shape.are_contact_events_enabled(shape_id:b2Shape)→enabled:boolean

Check if contact events are enabled for a shape.

PARAMETERS

RETURNS

b2d.shape.are_hit_events_enabled()

b2d.shape.are_hit_events_enabled(shape_id:b2Shape)→enabled:boolean

Check if hit events are enabled for a shape.

PARAMETERS

RETURNS

b2d.shape.are_pre_solve_events_enabled()

b2d.shape.are_pre_solve_events_enabled(shape_id:b2Shape)→enabled:boolean

Check if pre-solve events are enabled for a shape.

PARAMETERS

RETURNS

b2d.shape.are_sensor_events_enabled()

b2d.shape.are_sensor_events_enabled(shape_id:b2Shape)→enabled:boolean

Check if sensor events are enabled for a shape.

PARAMETERS

RETURNS

b2d.shape.enable_contact_events()

b2d.shape.enable_contact_events(shape_id:b2Shape, enable:boolean)

Enable or disable contact events for a shape.

PARAMETERS

b2d.shape.enable_hit_events()

b2d.shape.enable_hit_events(shape_id:b2Shape, enable:boolean)

Enable or disable hit events for a shape.

PARAMETERS

b2d.shape.enable_pre_solve_events()

b2d.shape.enable_pre_solve_events(shape_id:b2Shape, enable:boolean)

Enable or disable pre-solve events for a shape.

PARAMETERS

b2d.shape.enable_sensor_events()

b2d.shape.enable_sensor_events(shape_id:b2Shape, enable:boolean)

Enable or disable sensor events for a shape.

PARAMETERS

b2d.shape.get_body()

b2d.shape.get_body(shape_id:b2Shape)→body:b2Body

Get the body owning a shape.

PARAMETERS

RETURNS

b2d.shape.get_closest_point()

b2d.shape.get_closest_point(shape_id:b2Shape, target:vector3)→point:vector3

Get the closest point on a shape.

PARAMETERS

RETURNS

b2d.shape.get_contact_capacity()

b2d.shape.get_contact_capacity(shape_id:b2Shape)→capacity:integer

Get shape contact capacity.

PARAMETERS

RETURNS

b2d.shape.get_contact_data()

b2d.shape.get_contact_data(shape_id:b2Shape)→contacts:b2d.contact_data[]

Get touching contact data for a shape.

PARAMETERS

RETURNS

b2d.shape.get_mass_data()

b2d.shape.get_mass_data(shape_id:b2Shape)→data:b2d.mass_data

Get mass data for a shape.

PARAMETERS

RETURNS

b2d.shape.get_material()

b2d.shape.get_material(shape_id:b2Shape)→material:integer

Get shape material id.

PARAMETERS

RETURNS

b2d.shape.get_sensor_capacity()

b2d.shape.get_sensor_capacity(shape_id:b2Shape)→capacity:integer

Get sensor overlap capacity.

PARAMETERS

RETURNS

b2d.shape.get_sensor_overlaps()

b2d.shape.get_sensor_overlaps(shape_id:b2Shape)→overlaps:b2d.shape_info[]

Get sensor overlaps.

PARAMETERS

RETURNS

b2d.shape.get_shape()

b2d.shape.get_shape(shape_id:b2Shape)→shape:b2d.shape.definition

Get a shape's geometry.

PARAMETERS

RETURNS

b2d.shape.get_world()

b2d.shape.get_world(shape_id:b2Shape)→world:b2World

Get the world owning a shape.

PARAMETERS

RETURNS

b2d.shape.is_valid()

b2d.shape.is_valid(shape_id:b2Shape)→valid:boolean

Validate a shape handle.

PARAMETERS

RETURNS

b2d.shape.ray_cast()

b2d.shape.ray_cast(shape_id:b2Shape, origin:vector3, translation:vector3, [max_fraction:number])→hit:b2d.shape_cast_output|nil

Ray cast a shape directly.

PARAMETERS

RETURNS

b2d.shape.set_material()

b2d.shape.set_material(shape_id:b2Shape, material:integer)

Set shape material id.

PARAMETERS

b2d.shape.set_shape()

b2d.shape.set_shape(shape_id:b2Shape, definition:b2d.shape.definition, update_mass:boolean)

This updates the shape geometry using the same table format as b2d.body.create_shape and b2d.shape.get_shape. The body mass is not updated unless update_mass is true.

PARAMETERS

EXAMPLES

local body = b2d.get_body("#collisionobject")

-- Move a circle shape relative to the body origin.
local circle = b2d.shape.get_shape(body, 1)
circle.center = vmath.vector3(24, 0, 0)
b2d.shape.set_shape(body, 1, circle, true)

-- Replace a segment shape's local endpoints.
b2d.shape.set_shape(body, 2, {
    type = b2d.shape.SHAPE_TYPE_SEGMENT,
    v1 = vmath.vector3(-32, 0, 0),
    v2 = vmath.vector3( 32, 0, 0),
})

-- Update a box shape using the polygon box convenience format.
b2d.shape.set_shape(body, 3, {
    type = b2d.shape.SHAPE_TYPE_BOX,
    hx = 16,
    hy = 8,
    center = vmath.vector3(0, 20, 0),
    angle = math.rad(30),
}, true)