public static PdnGraphicsPath FromRegion(PdnRegion region)
{
Rectangle[] scans = region.GetRegionScansReadOnlyInt();
if (scans.Length == 1)
{
PdnGraphicsPath path = new PdnGraphicsPath();
path.AddRectangle(scans[0]);
path.CloseFigure();
return(path);
}
else
{
Rectangle bounds = region.GetBoundsInt();
BitVector2D stencil = new BitVector2D(bounds.Width, bounds.Height);
for (int i = 0; i < scans.Length; ++i)
{
Rectangle rect = scans[i];
rect.X -= bounds.X;
rect.Y -= bounds.Y;
stencil.SetUnchecked(rect, true);
}
PdnGraphicsPath path = PathFromStencil(stencil, new Rectangle(0, 0, stencil.Width, stencil.Height));
using (Matrix matrix = new Matrix())
{
matrix.Reset();
matrix.Translate(bounds.X, bounds.Y);
path.Transform(matrix);
}
return(path);
}
}
/// <summary>
/// Creates a graphics path from the given stencil buffer. It should be filled with 'true' values
/// to indicate the areas that should be outlined.
/// </summary>
/// <param name="stencil">The stencil buffer to read from. NOTE: The contents of this will be destroyed when this method returns.</param>
/// <param name="bounds">The bounding box within the stencil buffer to limit discovery to.</param>
/// <returns>A PdnGraphicsPath with traces that outline the various areas from the given stencil buffer.</returns>
public unsafe static PdnGraphicsPath PathFromStencil(IBitVector2D stencil, Rectangle bounds)
{
if (stencil.IsEmpty)
{
return(new PdnGraphicsPath());
}
PdnGraphicsPath ret = new PdnGraphicsPath();
Point start = bounds.Location;
Vector <Point> pts = new Vector <Point>();
int count = 0;
// find all islands
while (true)
{
bool startFound = false;
while (true)
{
if (stencil[start])
{
startFound = true;
break;
}
++start.X;
if (start.X >= bounds.Right)
{
++start.Y;
start.X = bounds.Left;
if (start.Y >= bounds.Bottom)
{
break;
}
}
}
if (!startFound)
{
break;
}
pts.Clear();
Point last = new Point(start.X, start.Y + 1);
Point curr = new Point(start.X, start.Y);
Point next = curr;
Point left = Point.Empty;
Point right = Point.Empty;
// trace island outline
while (true)
{
left.X = ((curr.X - last.X) + (curr.Y - last.Y) + 2) / 2 + curr.X - 1;
left.Y = ((curr.Y - last.Y) - (curr.X - last.X) + 2) / 2 + curr.Y - 1;
right.X = ((curr.X - last.X) - (curr.Y - last.Y) + 2) / 2 + curr.X - 1;
right.Y = ((curr.Y - last.Y) + (curr.X - last.X) + 2) / 2 + curr.Y - 1;
if (bounds.Contains(left) && stencil[left])
{
// go left
next.X += curr.Y - last.Y;
next.Y -= curr.X - last.X;
}
else if (bounds.Contains(right) && stencil[right])
{
// go straight
next.X += curr.X - last.X;
next.Y += curr.Y - last.Y;
}
else
{
// turn right
next.X -= curr.Y - last.Y;
next.Y += curr.X - last.X;
}
if (Math.Sign(next.X - curr.X) != Math.Sign(curr.X - last.X) ||
Math.Sign(next.Y - curr.Y) != Math.Sign(curr.Y - last.Y))
{
pts.Add(curr);
++count;
}
last = curr;
curr = next;
if (next.X == start.X && next.Y == start.Y)
{
break;
}
}
Point[] points = pts.ToArray();
Scanline[] scans = Utility.GetScans(points);
foreach (Scanline scan in scans)
{
stencil.Invert(scan);
}
ret.AddLines(points);
ret.CloseFigure();
}
return(ret);
}
/// <summary>
/// Creates a graphics path from the given stencil buffer. It should be filled with 'true' values
/// to indicate the areas that should be outlined.
/// </summary>
/// <param name="stencil">The stencil buffer to read from. NOTE: The contents of this will be destroyed when this method returns.</param>
/// <param name="bounds">The bounding box within the stencil buffer to limit discovery to.</param>
/// <returns>A PdnGraphicsPath with traces that outline the various areas from the given stencil buffer.</returns>
public unsafe static PdnGraphicsPath PathFromStencil(IBitVector2D stencil, Rectangle bounds)
{
if (stencil.IsEmpty)
{
return new PdnGraphicsPath();
}
PdnGraphicsPath ret = new PdnGraphicsPath();
Point start = bounds.Location;
Vector<Point> pts = new Vector<Point>();
int count = 0;
// find all islands
while (true)
{
bool startFound = false;
while (true)
{
if (stencil[start])
{
startFound = true;
break;
}
++start.X;
if (start.X >= bounds.Right)
{
++start.Y;
start.X = bounds.Left;
if (start.Y >= bounds.Bottom)
{
break;
}
}
}
if (!startFound)
{
break;
}
pts.Clear();
Point last = new Point(start.X, start.Y + 1);
Point curr = new Point(start.X, start.Y);
Point next = curr;
Point left = Point.Empty;
Point right = Point.Empty;
// trace island outline
while (true)
{
left.X = ((curr.X - last.X) + (curr.Y - last.Y) + 2) / 2 + curr.X - 1;
left.Y = ((curr.Y - last.Y) - (curr.X - last.X) + 2) / 2 + curr.Y - 1;
right.X = ((curr.X - last.X) - (curr.Y - last.Y) + 2) / 2 + curr.X - 1;
right.Y = ((curr.Y - last.Y) + (curr.X - last.X) + 2) / 2 + curr.Y - 1;
if (bounds.Contains(left) && stencil[left])
{
// go left
next.X += curr.Y - last.Y;
next.Y -= curr.X - last.X;
}
else if (bounds.Contains(right) && stencil[right])
{
// go straight
next.X += curr.X - last.X;
next.Y += curr.Y - last.Y;
}
else
{
// turn right
next.X -= curr.Y - last.Y;
next.Y += curr.X - last.X;
}
if (Math.Sign(next.X - curr.X) != Math.Sign(curr.X - last.X) ||
Math.Sign(next.Y - curr.Y) != Math.Sign(curr.Y - last.Y))
{
pts.Add(curr);
++count;
}
last = curr;
curr = next;
if (next.X == start.X && next.Y == start.Y)
{
break;
}
}
Point[] points = pts.ToArray();
Scanline[] scans = Utility.GetScans(points);
foreach (Scanline scan in scans)
{
stencil.Invert(scan);
}
ret.AddLines(points);
ret.CloseFigure();
}
return ret;
}
public static PdnGraphicsPath FromRegion(PdnRegion region)
{
Rectangle[] scans = region.GetRegionScansReadOnlyInt();
if (scans.Length == 1)
{
PdnGraphicsPath path = new PdnGraphicsPath();
path.AddRectangle(scans[0]);
path.CloseFigure();
return path;
}
else
{
Rectangle bounds = region.GetBoundsInt();
BitVector2D stencil = new BitVector2D(bounds.Width, bounds.Height);
for (int i = 0; i < scans.Length; ++i)
{
Rectangle rect = scans[i];
rect.X -= bounds.X;
rect.Y -= bounds.Y;
stencil.SetUnchecked(rect, true);
}
PdnGraphicsPath path = PathFromStencil(stencil, new Rectangle(0, 0, stencil.Width, stencil.Height));
using (Matrix matrix = new Matrix())
{
matrix.Reset();
matrix.Translate(bounds.X, bounds.Y);
path.Transform(matrix);
}
return path;
}
}
