public static void GenerateMSDF(Bitmap <Color4b> output, Shape shape, Rectangle region, double range, Vector2 scale, Vector2 translate, double edgeThreshold)
{
int contourCount = shape.Contours.Count;
int[] windings = new int[contourCount];
for (int i = 0; i < shape.Contours.Count; i++)
{
windings[i] = shape.Contours[i].Winding;
}
int xStart = Math.Min(Math.Max(0, (int)region.Left), output.Width);
int yStart = Math.Min(Math.Max(0, (int)region.Top), output.Height);
int xEnd = Math.Min(Math.Max(0, (int)region.Right), output.Width);
int yEnd = Math.Min(Math.Max(0, (int)region.Bottom), output.Height);
MultiDistance[] contourSD = new MultiDistance[contourCount];
for (int y = yStart; y < yEnd; y++)
{
int row = shape.InverseYAxis ? yEnd - (y - yStart) - 1 : y;
for (int x = xStart; x < xEnd; x++)
{
Vector2 p = (new Vector2(x, y) - region.Position - translate) / scale;
output[x, row] = new Color4b(EvaluateMSDF(shape, windings, contourSD, p, range), 255);
}
}
}
static Color3 EvaluateMSDF(Shape shape, int[] windings, MultiDistance[] contourSD, Vector2 p, double range)
{
int contourCount = contourSD.Length;
p += new Vector2(0.5f, 0.5f);
EdgePoint sr = new EdgePoint {
minDistance = new SignedDistance(-1e240, 1)
};
EdgePoint sg = new EdgePoint {
minDistance = new SignedDistance(-1e240, 1)
};
EdgePoint sb = new EdgePoint {
minDistance = new SignedDistance(-1e240, 1)
};
double d = Math.Abs(SignedDistance.Infinite.distance);
double negDist = -SignedDistance.Infinite.distance;
double posDist = SignedDistance.Infinite.distance;
int winding = 0;
for (int i = 0; i < contourCount; i++)
{
Contour contour = shape.Contours[i];
EdgePoint r = new EdgePoint {
minDistance = new SignedDistance(-1e240, 1)
};
EdgePoint g = new EdgePoint {
minDistance = new SignedDistance(-1e240, 1)
};
EdgePoint b = new EdgePoint {
minDistance = new SignedDistance(-1e240, 1)
};
for (int j = 0; j < contour.Edges.Count; j++)
{
EdgeSegment edge = contour.Edges[j];
double param;
SignedDistance distance = edge.GetSignedDistance(p, out param);
if ((edge.Color & EdgeColor.Red) == EdgeColor.Red && distance < r.minDistance)
{
r.minDistance = distance;
r.nearEdge = edge;
r.nearParam = param;
}
if ((edge.Color & EdgeColor.Green) == EdgeColor.Green && distance < g.minDistance)
{
g.minDistance = distance;
g.nearEdge = edge;
g.nearParam = param;
}
if ((edge.Color & EdgeColor.Blue) == EdgeColor.Blue && distance < b.minDistance)
{
b.minDistance = distance;
b.nearEdge = edge;
b.nearParam = param;
}
}
if (r.minDistance < sr.minDistance)
{
sr = r;
}
if (g.minDistance < sg.minDistance)
{
sg = g;
}
if (b.minDistance < sb.minDistance)
{
sb = b;
}
double medMinDistance = Math.Abs(Median(r.minDistance.distance, g.minDistance.distance, b.minDistance.distance));
if (medMinDistance < d)
{
d = medMinDistance;
winding = -windings[i];
}
if (r.nearEdge != null)
{
r.nearEdge.DistanceToPseudoDistance(ref r.minDistance, p, r.nearParam);
}
if (g.nearEdge != null)
{
g.nearEdge.DistanceToPseudoDistance(ref g.minDistance, p, g.nearParam);
}
if (b.nearEdge != null)
{
b.nearEdge.DistanceToPseudoDistance(ref b.minDistance, p, b.nearParam);
}
medMinDistance = Median(r.minDistance.distance, g.minDistance.distance, b.minDistance.distance);
contourSD[i].r = r.minDistance.distance;
contourSD[i].g = g.minDistance.distance;
contourSD[i].b = b.minDistance.distance;
contourSD[i].med = medMinDistance;
if (windings[i] > 0 && medMinDistance >= 0 && Math.Abs(medMinDistance) < Math.Abs(posDist))
{
posDist = medMinDistance;
}
if (windings[i] < 0 && medMinDistance <= 0 && Math.Abs(medMinDistance) < Math.Abs(negDist))
{
negDist = medMinDistance;
}
}
if (sr.nearEdge != null)
{
sr.nearEdge.DistanceToPseudoDistance(ref sr.minDistance, p, sr.nearParam);
}
if (sg.nearEdge != null)
{
sg.nearEdge.DistanceToPseudoDistance(ref sg.minDistance, p, sg.nearParam);
}
if (sb.nearEdge != null)
{
sb.nearEdge.DistanceToPseudoDistance(ref sb.minDistance, p, sb.nearParam);
}
MultiDistance msd = new MultiDistance {
r = SignedDistance.Infinite.distance,
g = SignedDistance.Infinite.distance,
b = SignedDistance.Infinite.distance,
med = SignedDistance.Infinite.distance,
};
if (posDist >= 0 && Math.Abs(posDist) <= Math.Abs(negDist))
{
msd.med = SignedDistance.Infinite.distance;
winding = 1;
for (int i = 0; i < contourCount; i++)
{
if (windings[i] > 0 && contourSD[i].med > msd.med && Math.Abs(contourSD[i].med) < Math.Abs(negDist))
{
msd = contourSD[i];
}
}
}
else if (negDist <= 0 && Math.Abs(negDist) <= Math.Abs(posDist))
{
msd.med = -SignedDistance.Infinite.distance;
winding = -1;
for (int i = 0; i < contourCount; i++)
{
if (windings[i] < 0 && contourSD[i].med < msd.med && Math.Abs(contourSD[i].med) < Math.Abs(posDist))
{
msd = contourSD[i];
}
}
}
for (int i = 0; i < contourCount; i++)
{
if (windings[i] != winding && Math.Abs(contourSD[i].med) < Math.Abs(msd.med))
{
msd = contourSD[i];
}
}
if (Median(sr.minDistance.distance, sg.minDistance.distance, sb.minDistance.distance) == msd.med)
{
msd.r = sr.minDistance.distance;
msd.g = sg.minDistance.distance;
msd.b = sb.minDistance.distance;
}
return(new Color3((float)(msd.r / range) + 0.5f, (float)(msd.g / range) + 0.5f, (float)(msd.b / range) + 0.5f));
}
