org.sunflow.core
Class Ray

java.lang.Object
  org.sunflow.core.Ray

public final class Ray
extends java.lang.Object

This class represents a ray as a oriented half line segment. The ray direction is always normalized. The valid region is delimted by two distances along the ray, tMin and tMax.

Field Summary

float	dx
float	dy
float	dz
float	ox
float	oy
float	oz

Constructor Summary

Ray(float ox, float oy, float oz, float dx, float dy, float dz)
Creates a new ray that points from the given origin to the given direction.

Ray(Point3 a, Point3 b)
Creates a new ray that points from point a to point b.

Ray(Point3 o, Vector3 d)
Creates a new ray that points from the given origin to the given direction.

Method Summary

float	dot(float vx, float vy, float vz) Computes the dot product of an arbitrary vector with the direction of the ray.
float	dot(Vector3 v) Computes the dot product of an arbitrary vector with the direction of the ray.
Vector3	getDirection() Creates a vector to represent the direction of the ray.
float	getMax() Gets the maximum distance along the ray.
float	getMin() Gets the minimum distance along the ray - usually 0.
Point3	getPoint(Point3 dest) Gets the end point of the ray.
boolean	isInside(float t) Checks to see if the specified distance falls within the valid range on this ray.
void	normalize() Normalize the direction component of the ray.
void	setMax(float t) Updates the maximum to the specified distance if and only if the new distance is smaller than the current one.
Ray	transform(Matrix4 m) Create a new ray by transforming the supplied one by the given matrix.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ox

public float ox

oy

public float oy

oz

public float oz

dx

public float dx

dy

public float dy

dz

public float dz

Constructor Detail

Ray

public Ray(float ox,
           float oy,
           float oz,
           float dx,
           float dy,
           float dz)

Creates a new ray that points from the given origin to the given direction. The ray has infinite length. The direction vector is normalized.

Parameters:

ox - ray origin x

oy - ray origin y

oz - ray origin z

dx - ray direction x

dy - ray direction y

dz - ray direction z

Ray

public Ray(Point3 o,
           Vector3 d)

Creates a new ray that points from the given origin to the given direction. The ray has infinite length. The direction vector is normalized.

Parameters:

o - ray origin

d - ray direction (need not be normalized)

Ray

public Ray(Point3 a,
           Point3 b)

Creates a new ray that points from point a to point b. The created ray will set tMin and tMax to limit the ray to the segment (a,b) (non-inclusive of a and b). This is often used to create shadow rays.

Parameters:

a - start point

b - end point

Method Detail

transform

public Ray transform(Matrix4 m)

Create a new ray by transforming the supplied one by the given matrix. If the matrix is null, the original ray is returned.

Parameters:

m - matrix to transform the ray by

normalize

public void normalize()

Normalize the direction component of the ray.

getMin

public final float getMin()

Gets the minimum distance along the ray - usually 0.

Returns:

value of the smallest distance along the ray

getMax

public final float getMax()

Gets the maximum distance along the ray. May be infinite.

Returns:

value of the largest distance along the ray

getDirection

public final Vector3 getDirection()

Creates a vector to represent the direction of the ray.

Returns:

a vector equal to the direction of this ray

isInside

public final boolean isInside(float t)

Checks to see if the specified distance falls within the valid range on this ray. This should always be used before an intersection with the ray is detected.

Parameters:

t - distance to be tested

Returns:

true if t falls between the minimum and maximum distance of this ray, false otherwise

getPoint

public final Point3 getPoint(Point3 dest)

Gets the end point of the ray. A reference to dest is returned to support chaining.

Parameters:

dest - reference to the point to store

Returns:

reference to dest

dot

public final float dot(Vector3 v)

Computes the dot product of an arbitrary vector with the direction of the ray. This method avoids having to call getDirection() which would instantiate a new Vector object.

Parameters:

v - vector

Returns:

dot product of the ray direction and the specified vector

dot

public final float dot(float vx,
                       float vy,
                       float vz)

Computes the dot product of an arbitrary vector with the direction of the ray. This method avoids having to call getDirection() which would instantiate a new Vector object.

Parameters:

vx - vector x coordinate

vy - vector y coordinate

vz - vector z coordinate

Returns:

dot product of the ray direction and the specified vector

setMax

public final void setMax(float t)

Updates the maximum to the specified distance if and only if the new distance is smaller than the current one.

Parameters:

t - new maximum distance