Sets n to the (unnormalised) normal of the triangle defined by points a, b and c. Effectively returns the sum of the three possible edge cross-products, for stability. The length of this vector is 2 x the area of the triangle.

Definition at line 35 of file VecUtil.cc.

Void FindMaxCmpts (const Colour & a, const Colour & b, Colour & c) [inline]

Definition at line 238 of file VecUtil.h.

Void FindMaxElts (const Vector & a, const Vector & b, Vector & c) [inline]

place max elts of a and b in c.

Definition at line 214 of file VecUtil.h.

Void FindMinCmpts (const Colour & a, const Colour & b, Colour & c) [inline]

Definition at line 245 of file VecUtil.h.

Void FindMinElts (const Vector & a, const Vector & b, Vector & c) [inline]

place min elts of a and b in c.

Definition at line 221 of file VecUtil.h.

Vector FindOrthoVector (const Vector & v) [inline]

Find a vector that is orthogonal to v.

Warning: the vector this routine returns is *not* normalised. (Though the length will be close to 1.)

Definition at line 98 of file VecUtil.h.

ClrReal MaxCmpt (const Colour & c) [inline]

equivalents of Elts routines for Colours.

Definition at line 228 of file VecUtil.h.

Int MaxCmptIndex (const Colour & c) [inline]

Definition at line 200 of file VecUtil.h.

GCLReal MaxElt (const Vector & v) [inline]

return max elt of v.

Definition at line 148 of file VecUtil.h.

Int MaxEltIndex (const Vector & v) [inline]

return index of max elt of v.

Definition at line 172 of file VecUtil.h.

ClrReal MinCmpt (const Colour & c) [inline]

Definition at line 233 of file VecUtil.h.

Int MinCmptIndex (const Colour & c) [inline]

Definition at line 186 of file VecUtil.h.

GCLReal MinElt (const Vector & v) [inline]

return min elt of v.

Definition at line 153 of file VecUtil.h.

Int MinEltIndex (const Vector & v) [inline]

return index of min elt of v.

Definition at line 158 of file VecUtil.h.

Bool PlaneIntersection (const Point & start, const Vector & direction, GCLReal d, const Vector & normal, GCLReal & t) [inline]

Intersect plane with ray.

Returns true if given ray intersects the plane specified by d and normal. (The plane equation is .) If there is an intersection, t is set, and the intersection point will be .

Definition at line 66 of file VecUtil.h.

Bool PointIsInsideTriangle (const Point & v0, const Point & v1, const Point & v2, const Point & point, Vector * coords = 0)

Test if the point is inside the given triangle.

Given a point lying in the plane of the triangle, we return false if it lies outside the triangle, and its barycentric coordinates if it lies inside.

Definition at line 84 of file VecUtil.cc.

GCLReal ProjectToBox (Point & min, Point & max, Point & p, Vector & r)

Project p in direction r on to bounding box min/max.

Returns t such that this projected point = p + t * r.

Definition at line 291 of file VecUtil.cc.

Vector RandomVector ()

Return random vector with components in [0, 1].

Definition at line 309 of file VecUtil.cc.

Bool Refract (GCLReal fromIndex, GCLReal toIndex, const Vector & v, const Vector & n, GCLReal cosNV, Vector & refractDir)

Calculates the refraction vector for the given parameters.

Returns true if total internal reflection occurs.

Definition at line 13 of file VecUtil.cc.

Void UnitDiskToUnitSquare (Coord in, Coord & out)

Unit disk to unit square transform from Shirley & Chiu.

Parameters:: in a point on radius 1 disk

out a point in [0,1]^2

Definition at line 248 of file VecUtil.cc.

Void UnitSquareToUnitDisc (Coord in, Coord & out)

Unit square to unit disk transform from Shirley & Chiu.

Parameters:: in a point in [0,1]^2

out a point on radius 1 disk

This transforms points on [0,1]^2 to points on unit disk centered at origin. Each "pie-slice" quadrant of square is handled as a seperate case. The bad floating point cases are all handled appropriately. The regions for (a,b) are:

 phi = pi/2
 -----*-----
 |\ /|
 | \ 2 / |
 | \ / |
 phi=pi* 3 * 1 *phi = 0
 | / \ |
 | / 4 \ |
 |/ \|
 -----*-----
 phi = 3pi/2

Definition at line 179 of file VecUtil.cc.

Void UpdateBounds (const Point & pt, Point & min, Point & max)

update min/max according to pt.

Definition at line 54 of file VecUtil.cc.