BV_Overlap Class Reference

A class for determining if geometry objects overlap. More...

#include <BV_Overlap.h>

List of all members.

Static Public Member Functions
static bool	doCoplanarTriTriOverlap (const bvTriangle &tri1, const bvTriangle &tri2, fpreal tol=0.0f)
	Returns true if two coplanar triangles overlap.
static bool	doTriTriOverlap (const bvTriangle &tri1, const bvTriangle &tri2, fpreal tol=0.0f)
	Returns true if two triangles overlap.
static bool	doTriTriOverlap (const bvTriangle &tri1, const bvTriangle &tri2, bool &coplanar, UT_Vector3 &isectpt1, UT_Vector3 &isectpt2, fpreal tol=0.0f)
	Returns the intersection points when two triangles overlap.
static bool	doCoplanarQuadQuadOverlap (const bvQuad &q1, const bvQuad &q2, fpreal tol=0.0f)
	Returns true if two coplanar quadrilaterals overlap.
static bool	doPlaneBoxOverlap (const UT_Vector3 &normal, const fpreal d, const UT_Vector3 &maxbox, fpreal tol=0.0f)
	Returns true if a plane and a box overlap.
static bool	doTriBoxOverlap (const bvTriangle &tri, const UT_Vector3 &ra, const UT_Matrix3 &R, const UT_Vector3 &T, bool lite=false)
static bool	doBoxBoxOverlap (const UT_Vector3 &ra, const UT_Vector3 &rb, const UT_Matrix3 &R, const UT_Vector3 &T, fpreal tol=0.f, bool lite=false)
static void	calcAABB (const UT_Vector3 &ra, const UT_DMatrix4 &xform, UT_Vector3 &rnew, UT_Vector3 &Tnew)
static void	calcAABB (const UT_Vector3 &ra, const UT_DMatrix4 &xform, const UT_Matrix3 &R, const UT_Vector3 &T, UT_Vector3 &rnew, UT_Vector3 &Tnew)
static bool	doBoxBoxOverlap (const UT_Vector3 &ra, const UT_Vector3 &rb, const UT_DMatrix4 &xform1, const UT_DMatrix4 &xform2, const UT_Matrix3 &R, const UT_Vector3 &T, fpreal tol, bool lite=false, bool useOBB=true)

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Detailed Description

A class for determining if geometry objects overlap.

Definition at line 46 of file BV_Overlap.h.

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Member Function Documentation

static void BV_Overlap::calcAABB	(	const UT_Vector3 &	ra,
		const UT_DMatrix4 &	xform,
		const UT_Matrix3 &	R,
		const UT_Vector3 &	T,
		UT_Vector3 &	rnew,
		UT_Vector3 &	Tnew
	)			[static]

static void BV_Overlap::calcAABB	(	const UT_Vector3 &	ra,
		const UT_DMatrix4 &	xform,
		UT_Vector3 &	rnew,
		UT_Vector3 &	Tnew
	)			[static]

Given an AABB (with radii ra -- half of dimension) and center at origin calculate an AABB (parallel to the original AABB) that contains the original AABB and an OBB by applying xform to the original AABB.

static bool BV_Overlap::doBoxBoxOverlap	(	const UT_Vector3 &	ra,
		const UT_Vector3 &	rb,
		const UT_DMatrix4 &	xform1,
		const UT_DMatrix4 &	xform2,
		const UT_Matrix3 &	R,
		const UT_Vector3 &	T,
		fpreal	tol,
		bool	lite = false,
		bool	useOBB = true
	)			[static]

Given two OBBs (second determined by a relative transform R & T), checks for overlaps between the OBBs with each containing one original OBB and the OBB after applying xform.

static bool BV_Overlap::doBoxBoxOverlap	(	const UT_Vector3 &	ra,
		const UT_Vector3 &	rb,
		const UT_Matrix3 &	R,
		const UT_Vector3 &	T,
		fpreal	tol = 0.f,
		bool	lite = false
	)			[static]

This checks for overlaps for two static OBBs. This method is based on the Seperating Axis Theorem (SAT). The lite version of this, algorithm, dubbed SAT-lite, satistically has only about 15% chance of reporting disjoint bounding boxes as intersecting. However, this may improve runtime in some situations since this is 2.5 times faster than the original SAT, by only checking the face-face axis (and ignoring the edges). This may generate false positives however.

static bool BV_Overlap::doCoplanarQuadQuadOverlap	(	const bvQuad &	q1,
		const bvQuad &	q2,
		fpreal	tol = 0.0f
	)			[static]

Returns true if two coplanar quadrilaterals overlap.

static bool BV_Overlap::doCoplanarTriTriOverlap	(	const bvTriangle &	tri1,
		const bvTriangle &	tri2,
		fpreal	tol = 0.0f
	)			[static]

Returns true if two coplanar triangles overlap.

static bool BV_Overlap::doPlaneBoxOverlap	(	const UT_Vector3 &	normal,
		const fpreal	d,
		const UT_Vector3 &	maxbox,
		fpreal	tol = 0.0f
	)			[static]

Returns true if a plane and a box overlap.

static bool BV_Overlap::doTriBoxOverlap	(	const bvTriangle &	tri,
		const UT_Vector3 &	ra,
		const UT_Matrix3 &	R,
		const UT_Vector3 &	T,
		bool	lite = false
	)			[static]

Uses the Seperating Axis Theorem (SAT) to test for triangle/box intersection. The lite version avoids edge tests, but may generate false positives.

static bool BV_Overlap::doTriTriOverlap	(	const bvTriangle &	tri1,
		const bvTriangle &	tri2,
		bool &	coplanar,
		UT_Vector3 &	isectpt1,
		UT_Vector3 &	isectpt2,
		fpreal	tol = 0.0f
	)			[static]

Returns the intersection points when two triangles overlap.

static bool BV_Overlap::doTriTriOverlap	(	const bvTriangle &	tri1,
		const bvTriangle &	tri2,
		fpreal	tol = 0.0f
	)			[static]

Returns true if two triangles overlap.

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

• BV/BV_Overlap.h