void ComputeBoundingBox(int index)
{
EnsureUndisposed();
if (bbmode != BoundingBoxMode.Automatic)
return;
BoundingBox bb = new BoundingBox(width - 1, height - 1, 0, 0);
Bitmap b = frames[index];
BitmapData bd = b.LockBits(new Rectangle(0, 0, width, height), ImageLockMode.ReadOnly, PixelFormat.Format32bppArgb);
for (int j = 0; j < height; j++)
{
for (int i = 0; i < width; i++)
{
int pixel = System.Runtime.InteropServices.Marshal.ReadInt32(bd.Scan0, bd.Stride * j + i * 4);
int alpha = (int)((uint)pixel >> 24);
if (alpha > tol)
{
if (bb.Left > i) bb.Left = i;
if (bb.Right < i) bb.Right = i;
if (bb.Top > j) bb.Top = j;
if (bb.Bottom < j) bb.Bottom = j;
}
}
}
b.UnlockBits(bd);
if (index >= bboxes.Count)
{
while (index >= bboxes.Count)
bboxes.Add(index == bboxes.Count ? bb : new BoundingBox());
}
else
bboxes[index] = bb;
}
public System.Collections.BitArray CollisionMask(int framenum)
{
EnsureUndisposed();
if (framenum >= frames.Count)
{
return(null);
}
if (!separatemasks)
{
framenum = 0;
}
BoundingBox bb = GetBoundingBox(framenum);
if (bb.Left > bb.Right || bb.Top > bb.Bottom)
{
return(null);
}
bb.Normalize();
int w = bb.Right - bb.Left + 1;
int h = bb.Bottom - bb.Top + 1;
System.Collections.BitArray mask = new System.Collections.BitArray(w * h);
switch (bbshape)
{
case BoundingBoxShape.Rectangle:
// The mask is a rectangle.
mask.SetAll(true);
break;
case BoundingBoxShape.Diamond:
case BoundingBoxShape.Disk:
// Use a lambda function for the shape: a disk or a diamond.
Func <double, double, bool> ftn =
bbshape == BoundingBoxShape.Disk ?
(Func <double, double, bool>)((double x, double y) => (x * x + y * y < 1.0)) :
(Func <double, double, bool>)((double x, double y) => (Math.Abs(x) + Math.Abs(y) < 1.0));
// Fill in the mask fitting the coordinates into the lambda function for the shape.
//GM8 BETA1/2/RC1 incorrect version (off-by-one and excessive rounding):
//int scalex = (bb.Right - bb.Left) >> 1;
//int scaley = (bb.Bottom - bb.Top) >> 1;
//for (int j = 0; j < h; j++)
// for (int i = 0; i < w; i++)
// mask[j * w + i] = ftn((double)(i - scalex) / (double)scalex, (double)(j - scaley) / (double)scaley);
// correct code:
double scalex = (double)(bb.Right - bb.Left + 1) * 0.5;
double scaley = (double)(bb.Bottom - bb.Top + 1) * 0.5;
for (int j = 0; j < h; j++)
{
for (int i = 0; i < w; i++)
{
mask[j * w + i] = ftn((double)(i - scalex) / scalex, (double)(j - scaley) / scaley);
}
}
break;
default:
// Generate a mask based on alpha tolerance on each pixel.
Bitmap b = frames[framenum];
BitmapData bd = b.LockBits(new Rectangle(bb.Left, bb.Top, w, h), ImageLockMode.ReadOnly, PixelFormat.Format32bppArgb);
for (int j = 0; j < h; j++)
{
for (int i = 0; i < w; i++)
{
mask[j * w + i] = (int)((uint)System.Runtime.InteropServices.Marshal.ReadInt32(bd.Scan0, (j + bb.Top) * bd.Stride + (i + bb.Left) * 4) >> 24) > tol;
}
}
b.UnlockBits(bd);
break;
}
return(mask);
}
public void SetBoundingBox(BoundingBox bbox)
{
EnsureUndisposed();
bbmode = BoundingBoxMode.Manual;
bboxes[0] = bbox;
}
public void SetBoundingBox(BoundingBox bbox)
{
EnsureUndisposed();
bbmode = BoundingBoxMode.Manual;
bboxes[0] = bbox;
}