Cute c2
From GiderosMobile
Supported platforms: 
Available since: Gideros 2022.6
Description
cute_c2 implements 2D collision detection routines that test for overlap, and optionally can find the collision manifold. The manifold contains all necessary information to prevent shapes from inter-penetrating, which is useful for character controllers, general physics simulation, and user-interface programming.
cute_c2 LUA binding for Gideros by rrraptor ;-)
To add the cute_c2 plugin:
require "CuteC2"
cute_c2 is available under 2 licenses: zlib license and Public Domain (www.unlicense.org) (you may choose the one you like) and is available at https://github.com/RandyGaul/cute_headers
Global functions
Objects
-- x, y (numbers): position
-- r (number): radius
Circle = CuteC2.circle(x, y, r)
-- minX, minY (numbers): top left corner position
-- maxX, maxY (numbers): bottom right corner position
-- anchor point is in top left corner
AABB = CuteC2.aabb(minX, minY, maxX, maxY)
-- x, y (numbers): position
-- h (number): height
-- r (number): radius
Capsule = CuteC2.capsule(x, y, h, r)
-- points (table): table of x/y pairs (example: {0,0, 100,50, 60,30, 40,90})
-- !!!IMPORTANT NOTE!!! maximum amount of points pairs is 8, everything beyond this limit is ignored
Poly = CuteC2.poly(points)
-- x1, y1 (numbers): start position
-- x2, y2 (numbers): destenation position (gets normalized)
-- len (number): ray lenght (default: distance between (x1, y1) and (x2, y2))
Ray = CuteC2.ray(x1, y1, x2, y2 [, len])
-- x, y (numbers): start position
-- rotation (number): facing angle (in radians)
-- len (number): ray lenght (default: 1)
Ray = CuteC2.rayFromRotation(x, y, rotation [, len])
-- x, y (numbers): position (default: (0, 0))
-- r (number): rotation (default: 0)
Transform = CuteC2.transform([x, y, r])
Functions
bool = CuteC2.circleToCircle(circle1, circle2)
bool = CuteC2.circleToAABB(circle, aabb)
bool = CuteC2.circleToCapsule(circle, capsule)
bool = CuteC2.AABBtoAABB(aabb1, aabb2)
bool = CuteC2.AABBtoCapsule(aabb, capsule)
bool = CuteC2.capsuleToCapsule(capsule1, capsule2)
bool = CuteC2.circleToPoly(circle, poly [, transform])
bool = CuteC2.AABBtoPoly(aabb, poly [, transform])
bool = CuteC2.capsuleToPoly(capsule, poly [, transform])
bool = CuteC2.polyToPoly(poly1, poly2 [, transform1, transform2])
bbol = CuteC2.collided(object1, object2 [, transform1, transform2])
bool = CuteC2.AABBtoPoint(aabb, x, y)
bool = CuteC2.circleToPoint(circle, x, y)
bool = CuteC2.capsuleToPoint(capsule, x, y)
bool = CuteC2.polyToPoint(poly, x, y [, transform])
result, normalX, normalY, t = CuteC2.castRay(ray, object [, transform])
result, normalX, normalY, t = CuteC2.castRay(rayX1, rayY1, rayX2, rayY2, rayLen, object [, transform])
-- t (number): value from raycast result
x, y = CuteC2.impact(ray, t)
x, y = CuteC2.impact(rayX1, rayY1, rayX2, rayY2, rayLen, t)
-- Mainfold (table):
-- {
-- count = number,
-- depth = {number1, number2},
-- contact_points = {
-- {x = number, y = number},
-- {x = number, y = number}
-- },
-- normal = {x = number, y = number}
-- }
Mainfold = CuteC2.collide(object1, object2 [, transform1, transform2])
Mainfold = CuteC2.circleToCircleManifold(circle1, circle2)
Mainfold = CuteC2.circleToAABBManifold(circle, aabb)
Mainfold = CuteC2.circleToCapsuleManifold(circle, capsule)
Mainfold = CuteC2.AABBtoAABBManifold(aabb1, aabb2)
Mainfold = CuteC2.AABBtoCapsuleManifold(aabb, capsule)
Mainfold = CuteC2.capsuleToCapsuleManifold(capsule1, capsule2)
Mainfold = CuteC2.circletoPolyManifold(circle, poly)
Mainfold = CuteC2.AABBtoPolyManifold(aabb, poly)
Mainfold = CuteC2.capsuleToPolyManifold(capsule, poly)
Mainfold = CuteC2.polyToPolyManifold(poly1, poly2)
Advanced functions
Check the [source code](https://github.com/RandyGaul/cute_headers/blob/df3b63e072afa275a72ce8aa7fce0428a5966e0c/cute_c2.h#L342) for more information
distance, aX, aY, bX, bY, iterations = CuteC2.GJK(object1, object2 [, transform1, transform2])
-- hit (bool): true if shapes were touching at the TOI, false if they never hit.
-- toi (number): The time of impact between two shapes.
-- nx, ny (numbers): Surface normal from shape A to B at the time of impact.
-- px, py (numbers): Point of contact between shapes A and B at time of impact.
-- iterations (number): Number of iterations the solver underwent.
hit, toi, nx, ny, px, py, iterations = CuteC2.TOI(object1, v1x, v1y, object2, v2x, v2y [, use_radius, transform1, transform2])
Circle
Circle:setPosition(x, y)
x, y = Circle:getPosition()
Circle:setX(x)
x = Circle:getX()
Circle:setY(y)
y = Circle:getY()
Circle:setRadius(radius)
radius = Circle:getRadius()
minX, minY, maxX, maxY = Circle:getBoundingBox()
x, y, radius = Circle:getData()
Circle:move(dx, dy)
Circle:inflate(skin_factor)
bool = Circle:hitTest(x, y)
result, normalX, normalY, t = Circle:rayTest(ray [, transform])
result, normalX, normalY, t = Circle:rayTest(rayX1, rayY1, rayX2, rayY2, rayLen [, transform])
AABB
-- x, y (number): top left corner position
AABB:setMinPosition(x, y)
x, y = AABB:getMinPosition()
-- x, y (number): bottom right corner position
AABB:setMaxPosition(x, y)
x, y = AABB:getMaxPosition()
-- x, y (number): center position
AABB:setPosition(x, y)
x, y = AABB:getPosition()
AABB:setMinX(x)
x = AABB:getMinX()
AABB:setMinY(y)
y = AABB:getMinY()
AABB:setMaxX(x)
x = AABB:getMaxX()
AABB:setMaxY(y)
y = AABB:getMaxY()
AABB:setX(x)
x = AABB:getX()
AABB:setY(y)
y = AABB:getY()
-- w, h (number): full size (relative to shape center)
AABB:setSize(w, h)
w, h = AABB:getSize()
-- w, h (number): half size (relative to shape center)
AABB:setHalfSize(w, h)
w, h = AABB:getHalfSize()
-- w (number): full width (relative to shape center)
AABB:setWidth(w)
w = AABB:getWidth()
-- h (number): full height (relative to shape center)
AABB:setHeight(h)
h = AABB:getHeight()
-- w (number): half width (relative to shape center)
AABB:setHalfWidth(w)
w = AABB:getHalfWidth()
-- h (number): half height (relative to shape center)
AABB:setHalfHeight(h)
h = AABB:getHalfHeight()
minX, minY, maxX, maxY = AABB:getBoundingBox()
minX, minY, maxX, maxY, fullW, fullH = AABB:getData()
AABB:move(dx, dy)
AABB:inflate(skin_factor)
bool = AABB:hitTest(x, y)
result, normalX, normalY, t = AABB:rayTest(ray [, transform])
result, normalX, normalY, t = AABB:rayTest(rayX1, rayY1, rayX2, rayY2, rayLen [, transform])
Capsule
, - ~ ~ ~ - ,-------------.-
, ' ' , |
, , | Radius
, , |
,- - - - - - -X-<Tip - - - -,-----|-
, , |
, , |
, , |
, X < Center , | Height
, , |
, , |
, | , |
,- - - - - - -X-<Base- - - -,-----|-
, , |
, , | Radius
, , ' |
' - , _ _ _ , '_ _ _ _ _ _ |_
-- x, y (number): center position
Capsule:setPosition(x, y)
x, y = Capsule:getPosition()
-- x, y (number): position of the top point
Capsule:setTipPosition(x, y)
x, y = Capsule:getTipPosition()
-- x, y (number): position of the bottom point
Capsule:setBasePosition(x, y)
x, y = Capsule:getBasePosition()
Capsule:setX(x)
x = Capsule:getX()
Capsule:setY(y)
y = Capsule:getY()
Capsule:setTipX(x)
x = Capsule:getTipX()
Capsule:setTipY(y)
y = Capsule:getTipY()
Capsule:setBaseX(x)
x = Capsule:getBaseX()
Capsule:setBaseY(y)
y = Capsule:getBaseY()
-- h (number): height
Capsule:setHeight(h)
h = Capsule:getHeight()
-- r (number): radius
Capsule:setRadius(r)
r = Capsule:getRadius()
Capsule:setSize(radius, height)
radius, height = Capsule:getSize()
minX, minY, maxX, maxY = Capsule:getBoundingBox()
tipX, tipY, baseX, baseY, radius = Capsule:getData()
Capsule:move(dx, dy)
Capsule:inflate(skin_factor)
bool = Capsule:hitTest(x, y)
result, normalX, normalY, t = Capsule:rayTest(ray [, transform])
result, normalX, normalY, t = Capsule:rayTest(rayX1, rayY1, rayX2, rayY2, rayLen [, transform])
Poly
-- points (table): table of x/y pairs (example: {0,0, 100,50, 60,30, 40,90})
Poly:setPoints(points)
-- points (table): table of x/y pairs (example: {{x=0,y=0}, {x=100,y=50}, {x=60,y=30}, {x=40,y=90}})
Poly:setPointsXY(points)
-- returns a table of x/ pairs ({{x=0,y=0,}, {x=10,y=0}, ...})
table = Poly:getPoints()
table = Poly:getNormals()
table = Poly:getRotatedPoints(transform)
table = Poly:getRotatedNormals(transform)
Poly:setVertex(index, x, y)
x, y = Poly:getVertex(index)
x = Poly:getVertexX(index)
y = Poly:getVertexY(index)
x, y = Poly:getRotatedVertex(index, transform)
x = Poly:getRotatedVertexX(index, transform)
y = Poly:getRotatedVertexY(index, transform)
-- return number of vertices
n = Poly:getVertexCount()
-- removes
Poly:removeVertex(index)
-- add new vertex
-- x, y (number): point coordinats (in local space)
-- index (number): where to insert (default: last index)
-- transform (Transform): Transform object to add point with respect to shape position and rotation
Poly:insertVertex(x, y [, index, transform])
-- if vertices is too far from origin, sets the origin in the middle of its bounding box
Poly:updateCenter()
-- scales object by a factor
Poly:inflate(skin_factor)
bool = Poly:hitTest(x, y [, transform])
minX, minY, maxX, maxY = Poly:getBoundingBox()
-- return a table with points & normals: {points = {...}, normals = {...}}
table = Poly:getData()
result, normalX, normalY, t = Poly:rayTest(ray [, transform])
result, normalX, normalY, t = Poly:rayTest(rayX1, rayY1, rayX2, rayY2, rayLen [, transform])
Ray
Please check (this thread) https://github.com/RandyGaul/cute_headers/issues/30 for more information about ray direction
Example
┌───────────────────────────────────┐
│ 0 1 2 3 4 5 6 7 8 9 │
│ ┌──┬──┬──┬──┬──┬──┬──┬──┬──┬──► │
│ │ │ │ │ │ │ │ │ │ │ x │
│1 ├──┼──S##┼──┼──┼──┼──┼──┼──┼── │
│ │ │ ## ## │ │ │ │ │ │ │
│2 ├──┼──#─#┼─##──┼──┼──┼──┼──┼─── │
│ │ │ # # │##│ │ │ │ │ │
│3 ├──┼──#──┼#─┼──##─┼──┼──┼──┼─── │
│ │ │ # │ #│ │ ## │ │ │ │
│4 ├──┼──#──┼──#──┼──┼##┼──┼──┼─── │
│ │ │ # │ │# │ │ ## │ │ │
│5 ├──┼──#──┼──┼─#┼──┼──┼─#N──┼─── │
│ │ │ # │ │ # │ │ │ │ │
│6 ├──┼──P──┼──┼──┼#─┼──┼──┼──┼─── │
│ │ │ │ │ │ │ #│ │ │ │ │
│7 ├──┼──┼──┼──┼──┼──T──┼──┼──┼─── │
│ │ │ │ │ │ │ │ │ │ │ │
│ │ │
│ ▼y │
└───────────────────────────────────┘
S = (2; 1) - origin position
T = (6; 7) - direction position
N = (8; 5) - new ray direction
P = (2; 6) - new ray direction
ray = CuteC2.ray(2, 1, 5, 7)
print(ray:getPosition()) --> 2, 1 (point "S")
print(ray:getTargetPosition()) --> 5, 7 (point "T")
print(ray:getLength()) --> 6.70
ray:normalize()
print(ray:getPosition()) --> 2, 1 (point "S")
print(ray:getTargetPosition()) --> (0.45, 0.89) direction vector
print(ray:getLength()) --> 1
ray:faceTo(8, 5) -- point "N"
print(ray:getLength()) --> 7.21
print(ray:getTargetPosition()) --> (0.83, 0.55)
print(ray:getFacePosition()) --> (8, 5)
ray:setDirection(math.pi - math.pi / 2) -- 90 deg
ray:setLength(5) -- point "P"
print(ray:getTargetPosition()) --> ~(0, 1)
print(ray:getFacePosition()) --> ~(2, 6)
API
ray:setPosition(x, y)
x, y = Ray:getPosition()
-- x, y (number): destenation point
ray:setTargetPosition(x, y)
x, y = Ray:getTargetPosition()
-- x, y (number): destenation point (target position gets normalized)
Ray:faceTo(x, y)
-- returns point in global space
x, y = Ray:getFacePosition()
x = Ray:getFaceX()
y = Ray:getFaceY()
Ray:setStartX(x)
x = Ray:getStartX()
Ray:setStartY(y)
y = Ray:getStartY()
Ray:setTargetX(x)
x = Ray:getTargetX()
Ray:setTargetY(y)
y = Ray:getTargetY()
Ray:setLength(len)
len = Ray:getLength()
-- normalzies the target position
-- set_len_to_one (bool)
Ray:normalize([set_len_to_one])
-- normalzies the target position
Ray:setDirection(radians)
radians = Ray:getDirection()
-- move original position (but not target!)
Ray:move(dx, dy)
startX, startY, directionX, directionY, len = Poly:getData()
Transform
Transform:setPosition(x, y)
x, y = Transform:getPosition()
Transform:setX(x)
x = Transform:getX()
Transform:setY(y)
y = Transform:getY()
Transform:move(deltaX, deltaY)
Transform:setRotation(radians)
radians = Transform:getRotation()
Transform:rotate(amount_in_radians)
Transform:move(dx, dy)
-- returns cos & sin of current rotation angle
cos, sin = Transform:getCosSin()
Shape types
CuteC2.TYPE_NONE
CuteC2.TYPE_CIRCLE
CuteC2.TYPE_AABB
CuteC2.TYPE_CAPSULE
CuteC2.TYPE_POLY
Example:
circle = CuteC2.circle(100, 200, 15)
print(circle.__shapeType == CuteC2.TYPE_CIRCLE) -- true
Example
Methods |
EventsConstants |
