decCollisionDetection Class Reference

Collection of collision detection routines. More...

#include <decCollisionDetection.h>

List of all members.

Public Types
enum	eIntersectionResult { eirInside, eirPartial, eirOutside }
	Intersection test results. More...
Static Public Member Functions
static bool	AABoxHitsAABox (const decVector &minExtend1, const decVector &maxExtend1, const decVector &minExtend2, const decVector &maxExtend2)
	Determines if two axis aligned boxes defined by their extends intersect.
static int	AABoxIntersectsAABox (const decVector &minExtend1, const decVector &maxExtend1, const decVector &minExtend2, const decVector &maxExtend2)
	Determines how the first axis aligned box intersects the second one.
static bool	RayHitsBox (const decVector &rayOrigin, const decVector &rayDirection, const decVector &boxCenter, const decVector &boxHalfExtends, float &hitDistance)
	Determines if a ray hits an axis aligned box.
static bool	RayHitsCapsule (const decVector &rayOrigin, const decVector &rayDirection, const decVector &capsuleCenter, float capsuleHalfHeight, float capsuleRadius, float &hitDistance)
	Determines if a ray hits a capsule with uniform radius oriented along the Y-Axis.
static bool	RayHitsCylinder (const decVector &rayOrigin, const decVector &rayDirection, const decVector &cylinderCenter, float cylinderHalfHeight, float cylinderRadius, float &hitDistance)
	Determines if a ray hits a cylinder with uniform radius oriented along the Y-Axis.
static bool	RayHitsTaperedCapsule (const decVector &rayOrigin, const decVector &rayDirection, const decVector &capsuleCenter, float capsuleHalfHeight, float capsuleTopRadius, float capsuleBottomRadius, float &hitDistance)
	Determines if a ray hits a tapered capsule oriented along the Y-Axis.
static bool	RayHitsTaperedCylinder (const decVector &rayOrigin, const decVector &rayDirection, const decVector &cylinderCenter, float cylinderHalfHeight, float cylinderTopRadius, float cylinderBottomRadius, float &hitDistance)
	Determines if a ray hits a tapered cylinder oriented along the Y-Axis.
static bool	RayHitsTriangle (const decVector &rayOrigin, const decVector &rayDirection, const decVector &tri1, const decVector &tri2, const decVector &tri3)
	Determines if a ray hits a triangle.
static bool	RayHitsTriangle (const decVector &rayOrigin, const decVector &rayDirection, const decVector &tri1, const decVector &tri2, const decVector &tri3, const decVector &trinormal)
	Determines if a ray hits a triangle using a precalculated triangle normal.
static float	SphereMoveHitsSphere (const decVector &sphere1Center, float sphere1Radius, const decVector &sphere2Center, float sphere2Radius, const decVector &displacement, decVector *normal)
	Determines if a sphere collides with another sphere while moving.
Closest Point Routines
static decVector	ClosestPointOnLine (const decVector &la, const decVector &lb, const decVector &p)
	Retrieves the closest point on a line to another point.
static decVector	ClosestPointOnTriangle (const decVector &tp1, const decVector &tp2, const decVector &tp3, const decVector &p)
	Retrieves the closest point on a triangle to a given point.
static decVector	ClosestPointOnQuad (const decVector &tp1, const decVector &tp2, const decVector &tp3, const decVector &tp4, const decVector &p)
	Retrieves the closest point on a quad to a given point.
Intersection Routines
static float	RayPlane (const decVector &pp, const decVector &pn, const decVector &rp, const decVector &rd)
	Intersections a ray with a plane.
static float	RaySphere (const decVector &rp, const decVector &rd, const decVector &sc, float sr)
	Intersections a ray with a sphere.
Distance Routines
static float	SegmentSegmentDistance (const decVector &as, const decVector &ae, const decVector &bs, const decVector &be)
	Retrieves the smallest distance of a line segment to another line segment.
Collision Tests
static bool	PointInTriangle (const decVector &tp1, const decVector &tp2, const decVector &tp3, const decVector &p)
	Determines if a point is inside a triangle.
static bool	PointInTriangle (const decVector &tp1, const decVector &tp2, const decVector &tp3, const decVector &tnormal, const decVector &p)
	Determines if a point is inside a triangle.
static bool	PointInQuad (const decVector &tp1, const decVector &tp2, const decVector &tp3, const decVector &tp4, const decVector &p)
	Determines if a point is inside a quad.
static bool	RayHitsSphere (const decVector &rayOrigin, const decVector &rayDirection, const decVector &sphereCenter, float sphereRadius, float &hitDistance)
	Determines if a ray hits a sphere.
static bool	SphereHitsSphere (const decVector &sphere1Center, float sphere1Radius, const decVector &sphere2Center, float sphere2Radius)
	Determines if a sphere collides with another sphere.
Side Test Routines
static int	PointOnPlaneSide (const decVector &pp, const decVector &pn, const decVector &p)
	Determines on which side of a plane the given point lies in respect to the plane normal.

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Detailed Description

Collection of collision detection routines.

Contains a set of collision detection routines used often in a game engine or similar 3D project. Some collision routines from collision volumes have been moved over here as they can be used then also by scripting modules which do not want to create collision volume objects for doing collision detection.

Author:

Plüss Roland

Version:

1.0

Date:

2008

---

Member Enumeration Documentation

enum decCollisionDetection::eIntersectionResult

Intersection test results.

Enumerator:

eirInside	Fully inside.
eirPartial	Partiall inside.
eirOutside	Fully outside.

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Member Function Documentation

static bool decCollisionDetection::AABoxHitsAABox	(	const decVector &	minExtend1,
		const decVector &	maxExtend1,
		const decVector &	minExtend2,
		const decVector &	maxExtend2
	)		[inline, static]

Determines if two axis aligned boxes defined by their extends intersect.

Parameters:

minExtend1	Minimum extend of the first box.
maxExtend1	Maximum extend of the first box.
minExtend2	Minimum extend of the second box.
maxExtend2	Maximum extend of the second box.

Returns:

True if the boxes intersect.

static int decCollisionDetection::AABoxIntersectsAABox	(	const decVector &	minExtend1,
		const decVector &	maxExtend1,
		const decVector &	minExtend2,
		const decVector &	maxExtend2
	)		[static]

Determines how the first axis aligned box intersects the second one.

Parameters:

minExtend1	Minimum extend of the first box.
maxExtend1	Maximum extend of the first box.
minExtend2	Minimum extend of the second box.
maxExtend2	Maximum extend of the second box.

Returns:

Intersection result one of eir* .

static decVector decCollisionDetection::ClosestPointOnLine	(	const decVector &	la,
		const decVector &	lb,
		const decVector &	p
	)		[static]

Retrieves the closest point on a line to another point.

Parameters:

la	Begin of line.
lb	End of line.
p	Point to check.

static decVector decCollisionDetection::ClosestPointOnQuad	(	const decVector &	tp1,
		const decVector &	tp2,
		const decVector &	tp3,
		const decVector &	tp4,
		const decVector &	p
	)		[static]

Retrieves the closest point on a quad to a given point.

The corners of the quad have to be coplanar or the result is is falsified.

Parameters:

tp1	First quad point.
tp2	Second quad point.
tp3	Third quad point.
tp4	Fourth quad point.
p	Point to check.

static decVector decCollisionDetection::ClosestPointOnTriangle	(	const decVector &	tp1,
		const decVector &	tp2,
		const decVector &	tp3,
		const decVector &	p
	)		[static]

Retrieves the closest point on a triangle to a given point.

Parameters:

tp1	First triangle point.
tp2	Second triangle point.
tp3	Third triangle point.
p	Point to check.

static bool decCollisionDetection::PointInQuad	(	const decVector &	tp1,
		const decVector &	tp2,
		const decVector &	tp3,
		const decVector &	tp4,
		const decVector &	p
	)		[static]

Determines if a point is inside a quad.

The point and the all corners of the quad have to be coplanar for this test to work.

Parameters:

tp1	First quad point.
tp2	Second quad point.
tp3	Third quad point.
tp4	Fourth quad point.
p	Point to check.

static bool decCollisionDetection::PointInTriangle	(	const decVector &	tp1,
		const decVector &	tp2,
		const decVector &	tp3,
		const decVector &	tnormal,
		const decVector &	p
	)		[static]

Determines if a point is inside a triangle.

The point has to be coplanar with the triangle for this test to work.

Parameters:

tp1	First triangle point.
tp2	Second triangle point.
tp3	Third triangle point.
tnormal	Triangle normal.
p	Point to check.

static bool decCollisionDetection::PointInTriangle	(	const decVector &	tp1,
		const decVector &	tp2,
		const decVector &	tp3,
		const decVector &	p
	)		[static]

Determines if a point is inside a triangle.

The point has to be coplanar with the triangle for this test to work.

Parameters:

tp1	First triangle point.
tp2	Second triangle point.
tp3	Third triangle point.
p	Point to check.

static int decCollisionDetection::PointOnPlaneSide	(	const decVector &	pp,
		const decVector &	pn,
		const decVector &	p
	)		[inline, static]

Determines on which side of a plane the given point lies in respect to the plane normal.

Parameters:

pp	Plane point.
pn	Plane normal.
p	Point to test.

Returns:

1 if in front side, -1 if on back side or 0 if coplanar

static bool decCollisionDetection::RayHitsBox	(	const decVector &	rayOrigin,
		const decVector &	rayDirection,
		const decVector &	boxCenter,
		const decVector &	boxHalfExtends,
		float &	hitDistance
	)		[static]

Determines if a ray hits an axis aligned box.

Parameters:

rayOrigin	Origin of the ray.
rayDirection	Normalized direction of the ray.
boxCenter	Center of the box.
boxHalfExtends	Half extends of the spherbox. All components have to be greater than 0.
hitDistance	If the ray hits this will be set to the distance from the ray origin to the collision point.

Returns:

True if the ray hits the box.

static bool decCollisionDetection::RayHitsCapsule	(	const decVector &	rayOrigin,
		const decVector &	rayDirection,
		const decVector &	capsuleCenter,
		float	capsuleHalfHeight,
		float	capsuleRadius,
		float &	hitDistance
	)		[static]

Determines if a ray hits a capsule with uniform radius oriented along the Y-Axis.

Parameters:

rayOrigin	Origin of the ray.
rayDirection	Normalized direction of the ray.
capsuleCenter	Center of the capsule.
capsuleHalfHeight	Half height of capsule. Has to be greater than 0.
capsuleRadius	Radius of the capsule. Has to be greater than 0.
hitDistance	If the ray hits this will be set to the distance from the ray origin to the collision point.

Returns:

True if the ray hits the capsule

static bool decCollisionDetection::RayHitsCylinder	(	const decVector &	rayOrigin,
		const decVector &	rayDirection,
		const decVector &	cylinderCenter,
		float	cylinderHalfHeight,
		float	cylinderRadius,
		float &	hitDistance
	)		[static]

Determines if a ray hits a cylinder with uniform radius oriented along the Y-Axis.

Parameters:

rayOrigin	Origin of the ray.
rayDirection	Normalized direction of the ray.
cylinderCenter	Center of the cylinder.
cylinderHalfHeight	Half height of cylinder. Has to be greater than 0.
cylinderRadius	Radius of the cylinder. Has to be greater than 0.
hitDistance	If the ray hits this will be set to the distance from the ray origin to the collision point.

Returns:

True if the ray hits the cylinder.

static bool decCollisionDetection::RayHitsSphere	(	const decVector &	rayOrigin,
		const decVector &	rayDirection,
		const decVector &	sphereCenter,
		float	sphereRadius,
		float &	hitDistance
	)		[static]

Determines if a ray hits a sphere.

Parameters:

rayOrigin	Origin of the ray.
rayDirection	Normalized direction of the ray.
sphereCenter	Center of the sphere.
sphereRadius	Radius of the sphere. Has to be greater than 0.
hitDistance	If the ray hits this will be set to the distance from the ray origin to the collision point.

Returns:

True if the ray hits the sphere.

static bool decCollisionDetection::RayHitsTaperedCapsule	(	const decVector &	rayOrigin,
		const decVector &	rayDirection,
		const decVector &	capsuleCenter,
		float	capsuleHalfHeight,
		float	capsuleTopRadius,
		float	capsuleBottomRadius,
		float &	hitDistance
	)		[static]

Determines if a ray hits a tapered capsule oriented along the Y-Axis.

Parameters:

rayOrigin	Origin of the ray.
rayDirection	Normalized direction of the ray.
capsuleCenter	Center of the capsule.
capsuleHalfHeight	Half height of capsule. Has to be greater than 0.
capsuleTopRadius	Radius of the top cap of the capsule. Has to be greater than 0.
capsuleBottomRadius	Radius of the bottom cap of the capsule. Has to be greater than 0.
hitDistance	If the ray hits this will be set to the distance from the ray origin to the collision point.

Returns:

True if the ray hits the capsule.

static bool decCollisionDetection::RayHitsTaperedCylinder	(	const decVector &	rayOrigin,
		const decVector &	rayDirection,
		const decVector &	cylinderCenter,
		float	cylinderHalfHeight,
		float	cylinderTopRadius,
		float	cylinderBottomRadius,
		float &	hitDistance
	)		[static]

Determines if a ray hits a tapered cylinder oriented along the Y-Axis.

Parameters:

rayOrigin	Origin of the ray.
rayDirection	Normalized direction of the ray.
cylinderCenter	Center of the cylinder.
cylinderHalfHeight	Half height of cylinder. Has to be greater than 0.
cylinderTopRadius	Radius of the top cap of the cylinder. Has to be greater than 0.
cylinderBottomRadius	Radius of the bottom cap of the cylinder. Has to be greater than 0.
hitDistance	If the ray hits this will be set to the distance from the ray origin to the collision point.

Returns:

True if the ray hits the cylinder.

static bool decCollisionDetection::RayHitsTriangle	(	const decVector &	rayOrigin,
		const decVector &	rayDirection,
		const decVector &	tri1,
		const decVector &	tri2,
		const decVector &	tri3
	)		[static]

Determines if a ray hits a triangle.

Parameters:

rayOrigin	Origin of the ray.
rayDirection	Normalized direction of the ray.
tri1	First point of the triangle.
tri2	Second point of the triangle.
tri3	Third point of the triangle.

Returns:

True if the ray hits the triangle.

static bool decCollisionDetection::RayHitsTriangle	(	const decVector &	rayOrigin,
		const decVector &	rayDirection,
		const decVector &	tri1,
		const decVector &	tri2,
		const decVector &	tri3,
		const decVector &	trinormal
	)		[static]

Determines if a ray hits a triangle using a precalculated triangle normal.

Parameters:

rayOrigin	Origin of the ray.
rayDirection	Normalized direction of the ray.
tri1	First point of the triangle.
tri2	Second point of the triangle.
tri3	Third point of the triangle.
trinormal	Normal of the triangle.

Returns:

True if the ray hits the triangle.

static float decCollisionDetection::RayPlane	(	const decVector &	pp,
		const decVector &	pn,
		const decVector &	rp,
		const decVector &	rd
	)		[static]

Intersections a ray with a plane.

Parameters:

pp	Plane position.
pn	Plane normal.
rp	Ray position.
rd	Ray direction.

Returns:

Distance to travel on the ray in his view direction to reach the collision point. If no collision occures ( because the ray is parallel to the plane ) -1 is returned.

static float decCollisionDetection::RaySphere	(	const decVector &	rp,
		const decVector &	rd,
		const decVector &	sc,
		float	sr
	)		[static]

Intersections a ray with a sphere.

Parameters:

rp	Ray position.
rd	Ray direction.
sc	Sphere center.
sr	Sphere radius.

Returns:

Distance to travel on the ray in his view direction to reach the collision point. If no collision occures ( because the ray is parallel to the plane ) -1 is returned.

static float decCollisionDetection::SegmentSegmentDistance	(	const decVector &	as,
		const decVector &	ae,
		const decVector &	bs,
		const decVector &	be
	)		[static]

Retrieves the smallest distance of a line segment to another line segment.

Parameters:

as	Segment a start position.
ae	Segment a end position.
bs	Segment b start position.
be	Segment b end position.

static bool decCollisionDetection::SphereHitsSphere	(	const decVector &	sphere1Center,
		float	sphere1Radius,
		const decVector &	sphere2Center,
		float	sphere2Radius
	)		[static]

Determines if a sphere collides with another sphere.

Parameters:

sphere1Center	Center of the first sphere.
sphere1Radius	Radius of the first sphere. Has to be greater than 0.
sphere2Center	Center of the second sphere.
sphere2Radius	Radius of the second sphere. Has to be greater than 0.

Returns:

True if the spheres collide.

static float decCollisionDetection::SphereMoveHitsSphere	(	const decVector &	sphere1Center,
		float	sphere1Radius,
		const decVector &	sphere2Center,
		float	sphere2Radius,
		const decVector &	displacement,
		decVector *	normal
	)		[static]

Determines if a sphere collides with another sphere while moving.

Parameters:

sphere1Center	Center of the first sphere.
sphere1Radius	Radius of the first sphere. Has to be greater than 0.
sphere2Center	Center of the second sphere.
sphere2Radius	Radius of the second sphere. Has to be greater than 0.
displacement	Displacement of the first sphere.
normal	Stores the collision normal into. Set to NULL if you do not require the normal.

Returns:

Time of impact. 0 correspondes to the beginning of the moving and 1 to moving along the entire displacement. Hence scaling the direction by the returned time of impact yields the displacement right up to the time of the collision. If no collision happend -1 is returned.

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The documentation for this class was generated from the following file:

• decCollisionDetection.h