internal Feature Evaluate(Vector2 point)
{
float top = 0;
float bottom = 0;
float left = 0;
float right = 0;
Feature feature = new Feature(point);
//validate point is in boundry
ComputeTopBottom(point,ref top,ref bottom);
ComputeLeftRight(point, ref left, ref right);
//interpolate to find distance
feature.Distance = GetBilinearInterpolatedDistance(point,top, bottom);
//calc gradient to find normal
feature.Normal = new Vector2(right - left, bottom - top);
feature.Normal.Normalize();
return feature;
}
internal Feature GetNearestFeature(Vector2 point)
{
Feature nearestFeature = new Feature();
nearestFeature.Distance = float.MaxValue;
for (int i = 0; i < _localVertices.Count; i++) {
Feature feature = GetNearestFeature(point, i);
if (feature.Distance < nearestFeature.Distance) {
nearestFeature = feature;
}
}
return nearestFeature;
}
internal Feature Evaluate(Vector2 point)
{
Feature feature = new Feature(point);
if(!Contains(point)){
return feature;
}
//find the cell
GridCell gridCell = FindContainingCell(point);
//if grid is outide the geometry, return feature with default values (distance=float.MaxValue)
if (gridCell.IsOutside) {
return feature;
}
//point is known to be inside the geometry so some work is needed to get the 'Feature' details.
feature = gridCell.Evaluate(point);
return feature;
}