private void BlitImage(byte[] image, Rect rect, bool flipVertical)
{
int srcPitch = rect.Width * 4;
int dstPitch = Dim * 4;
for (int y = 0; y < rect.Height; ++y) {
int srcOffset = (flipVertical ? rect.Height - y - 1 : y) * srcPitch;
int dstOffset = (rect.Y + y) * dstPitch + rect.X * 4;
Buffer.BlockCopy(image, srcOffset, Data, dstOffset, srcPitch);
}
}
public Node(Rect rect) {
Rect = rect;
Child0 = -1;
Child1 = -1;
Populated = false;
}
private int Insert(ref Node node, int nodeIndex, int width, int height)
{
// is this an internal node? of so, recurse
if (node.Child0 >= 0) {
var index = Insert(ref nodes[node.Child0], node.Child0, width, height);
if (index >= 0)
return index;
// try the second child, if the first failed
return Insert(ref nodes[node.Child1], node.Child1, width, height);
}
// this is a leaf node
// if this leaf is populated, then bail
if (node.Populated)
return -1;
// is it too small?
var r = node.Rect;
if (width > r.Width || height > r.Height)
return -1;
// or just right?
if (width == r.Width && height == r.Height) {
node.Populated = true;
return nodeIndex;
}
// if larger than necessary, we split across the longest axis,
// ensuring the first child is just big enough along this axis
int dw = r.Width - width;
int dh = r.Height - height;
Rect rect0, rect1;
if (dw > dh) {
rect0 = new Rect(r.X, r.Y, width, r.Height);
rect1 = new Rect(r.X + width, r.Y, r.Width - width, r.Height);
} else {
rect0 = new Rect(r.X, r.Y, r.Width, height);
rect1 = new Rect(r.X, r.Y + height, r.Width, r.Height - height);
}
int child0 = nodeCount;
node.Child0 = child0;
node.Child1 = child0 + 1;
// these may invalidate the node ref, so don't use it any more
AddNode(new Node(rect0));
AddNode(new Node(rect1));
// insert into first child which is just big enough along
// at least one axis
return Insert(ref nodes[child0], child0, width, height);
}
