/**
* Generate a ray passing though the specified point on the image plane.
* Additional random variables are provided for the lens to optionally
* compute depth-of-field or motion blur effects. Note that the camera may
* return <code>null</code> for invalid arguments or for pixels which
* don't project to anything.
*
* @param x x pixel coordinate
* @param y y pixel coordinate
* @param imageWidth width of the image in pixels
* @param imageHeight height of the image in pixels
* @param lensX a random variable in [0,1) to be used for DOF sampling
* @param lensY a random variable in [0,1) to be used for DOF sampling
* @param time a random variable in [0,1) to be used for motion blur
* sampling
* @return a ray passing through the specified pixel, or <code>null</code>
*/
public Ray getRay(float x, float y, int imageWidth, int imageHeight, double lensX, double lensY, float time)
{
Ray r = lens.getRay(x, y, imageWidth, imageHeight, lensX, lensY, time);
if (r != null)
{
// transform from camera space to world space
r = r.transform(c2w.sample((float)time));
// renormalize to account for scale factors embeded in the transform
r.normalize();
}
return(r);
}
/**
* Generate a ray passing though the specified point on the image plane.
* Additional random variables are provided for the lens to optionally
* compute depth-of-field or motion blur effects. Note that the camera may
* return <code>null</code> for invalid arguments or for pixels which
* don't project to anything.
*
* @param x x pixel coordinate
* @param y y pixel coordinate
* @param imageWidth width of the image in pixels
* @param imageHeight height of the image in pixels
* @param lensX a random variable in [0,1) to be used for DOF sampling
* @param lensY a random variable in [0,1) to be used for DOF sampling
* @param time a random variable in [0,1) to be used for motion blur
* sampling
* @return a ray passing through the specified pixel, or <code>null</code>
*/
public Ray getRay(float x, float y, int imageWidth, int imageHeight, double lensX, double lensY, double time)
{
Ray r = lens.getRay(x, y, imageWidth, imageHeight, lensX, lensY, time);
if (r != null)
{
if (c2w.Length == 1)
{
// regular sampling
r = r.transform(c2w[0]);
}
else
{
// motion blur
double nt = time * (c2w.Length - 1);
int idx0 = (int)nt;
int idx1 = Math.Min(idx0 + 1, c2w.Length - 1);
r = r.transform(Matrix4.blend(c2w[idx0], c2w[idx1], (float)(nt - idx0)));
}
// renormalize to account for scale factors embeded in the transform
r.normalize();
}
return(r);
}