public Point3Df GetSubPixelValue(Point2Df pt)
{
int loX = (int)Math.Floor(pt.X);
int loY = (int)Math.Floor(pt.Y);
int hiX = loX + 1;
int hiY = loY + 1;
double hiXWeight = pt.X - loX;
double hiYWeight = pt.Y - loY;
double loXWeight = 1 - hiXWeight;
double loYWeight = 1 - hiYWeight;
Point3Df weightedPixelVal;
// loXWeight and loYWeight will always be non-zero because of the relationship between
// pt.X/Y and loX/Y. We check to make sure hiXWeight and hiYWeight are not zero to make
// sure we don't wander out of the bounds of the image doing calculations
weightedPixelVal = GetPixelValue(loX, loY) * loXWeight * loYWeight;
if (hiXWeight != 0)
{
weightedPixelVal += GetPixelValue(hiX, loY) * hiXWeight * loYWeight;
}
if (hiYWeight != 0)
{
weightedPixelVal += GetPixelValue(loX, hiY) * loXWeight * hiYWeight;
}
if (hiXWeight != 0 && hiYWeight != 0)
{
weightedPixelVal += GetPixelValue(hiX, hiY) * hiXWeight * hiYWeight;
}
return(weightedPixelVal);
}
public Scanline(SceneView source, SceneView target, Point2Df sourcePixel,
double minDepth)
{
this.target = target;
// Center of projection of the two scene views. The subtraction is in reverse order
// because points translate in the direction opposite the COP shift
Point2Df copDiff = (Point2Df)(source.CenterOfProjection - target.CenterOfProjection);
// Distance to image plane
double d = source.DistanceToImagePlane;
Debug.Assert(d == target.DistanceToImagePlane);
// Store d * copDiff for efficiency
this.d_x_copDiff = d * copDiff;
// The start point represents the maximum depth, which is infinity. Pixels at infinity
// are at the same point in every perspective.
this.start = sourcePixel;
Point2Df end = new Point2Df(sourcePixel.X + d_x_copDiff.X / minDepth,
sourcePixel.Y - d_x_copDiff.Y / minDepth);
// Get the entire step from start to end
this.step = end - start;
// Scale the step so that it steps by one unit at a time either horizontally
// or vertically, whichever results in the fewest steps. This limits the
// resolution of the step to pixels. We don't have to worry about step being (0, 0)
// because end and start will never be colocated. Store the divisor so we can check
// against it while we're stepping.
this.maxSteps = Math.Max(Math.Abs(step.X), Math.Abs(step.Y));
this.step /= maxSteps;
prevMinDepth = DepthEstimator.Constants.InvalidDepth;
}
// Assumes the passed point is on the image plane and converts it to a 2D point in the
// top-left coordinate system of this view's image
public Point2Df ConvertFromWorld(Point2Df worldLoc)
{
return(new Point2Df(worldLoc.X + (double)(Image.Width - 1) / 2,
(double)(Image.Height - 1) / 2 - worldLoc.Y));
}
public Point2Df ConvertToWorld2D(Point2Df imageLoc)
{
return(new Point2Df(imageLoc.X - (double)(Image.Width - 1) / 2,
(double)(Image.Height - 1) / 2 - imageLoc.Y));
}
// CHECKME add version of this method that returns a Point2Df so we don't have to cast?
// Converts the passed image location in a top-left coordinate system to the equivalent
// world coordinates
public Point3Df ConvertToWorld3D(Point2Df imageLoc)
{
return(new Point3Df(ConvertToWorld2D(imageLoc),
DistanceToImagePlane));
}
public Point3Df(double x, double y, double z)
{
this.xy = new Point2Df(x, y);
this.z = z;
}
public Point3Df(Point2Df xy, double z) : this(xy.X, xy.Y, z)
{
}
public double Distance(Point2Df other)
{
return(Math.Sqrt(Math.Pow(this.x - other.x, 2) + Math.Pow(this.y - other.y, 2)));
}
public bool ContainsLoose(Point2Df pt)
{
return((pt.X > -0.5) && (pt.Y > -0.5) &&
(pt.X < this.Width - 0.5) && (pt.Y < this.Height - 0.5));
}
public bool Contains(Point2Df pt)
{
return((pt.X >= 0) && (pt.Y >= 0) &&
(pt.X < this.Width - 1) && (pt.Y < this.Height - 1));
}
