static bool minimizeArea(IntRectangle a, IntRectangle b, IntSize item)
{
var x0 = a.Width - item.Width;
var y0 = a.Height - item.Height;
var x1 = b.Width - item.Width;
var y1 = b.Height - item.Height;
return((x0 + y0) <= (x1 + y1));
}
internal unsafe Glyph(Font font, int index)
{
// Get glyph index (search)
Index = index;
Font = font;
// Get horizontal metrics (at raw scale)
int advWidth, bearing;
stbtt_GetGlyphHMetrics(Font.Info, Index, &advWidth, &bearing);
_advanceWidth = advWidth;
_bearing = bearing;
// Get glyph box info
int x0, x1, y0, y1;
stbtt_GetGlyphBitmapBox(Font.Info, Index, 1F, 1F, &x0, &y0, &x1, &y1);
Box = new IntRectangle(x0, y0, x1 - x0, y1 - y0);
}
private void Partition(IntRectangle itemRect)
{
var _rems = new List <IntRectangle>(128);
var _adds = new List <IntRectangle>(128);
// For all known free rects
foreach (var freeRect in _freeRects)
{
// If the free rect overlaps the item rect
if (freeRect.Overlaps(itemRect))
{
// Generate the new partitions
_adds.AddRange(GeneratePartitions(freeRect, itemRect));
// Remove the free rect
_rems.Add(freeRect);
}
// Remove other free rects that fully contained
foreach (var other in _freeRects)
{
if (freeRect == other)
{
continue;
}
if (freeRect.Contains(other))
{
_rems.Add(other);
}
}
}
// Perform mutations to rectangle set
foreach (var rect in _rems)
{
_freeRects.Remove(rect);
}
foreach (var rect in _adds)
{
_freeRects.Add(rect);
}
}
protected override bool Insert(IntSize itemSize, out IntRectangle itemRect)
{
// Try to find suitable rectangle for item
if (TryGetSuitableFreeRect(itemSize, out var freeRect))
{
// Store the element and associate rectangle
itemRect = new IntRectangle(freeRect.Position, itemSize);
// Partition and merge the free rects
Partition(itemRect);
return(true);
}
else
{
// Unable to fit item into any rectangle
itemRect = default;
return(false);
}
}
private bool TryGetSuitableFreeRect(IntSize itemSize, out IntRectangle freeRectangle)
{
freeRectangle = IntRectangle.Infinite;
var found = false;
//
foreach (var freeRect in _freeRects.OrderBy(r => r.Min.X + r.Min.Y))
{
// If the item can fit in here...
if (freeRect.Width >= itemSize.Width && freeRect.Height >= itemSize.Height)
{
// Select the free rect that causes minimal wasted area
if (minimizeArea(freeRectangle, freeRect, itemSize))
{
freeRectangle = freeRect;
found = true;
}
}
}
// Return if we found a suitable rectangle
return(found);
/// <summary>
/// Constructs a new nine slice.
/// </summary>
public NineSlice(Image frame, IntRectangle center)
{
Image = frame ?? throw new ArgumentNullException(nameof(frame));
Center = center;
}
internal GlyphMetrics(float advanceWidth, float bearing, IntRectangle box)
{
AdvanceWidth = advanceWidth;
Bearing = bearing;
_box = box;
}
private static IEnumerable <IntRectangle> GeneratePartitions(IntRectangle freeRect, IntRectangle itemRect)
{
var ht = itemRect.Top - freeRect.Top;
if (ht > 0)
{
yield return(new IntRectangle(freeRect.X, freeRect.Y, freeRect.Width, ht));
}
var hb = freeRect.Bottom - itemRect.Bottom;
if (hb > 0)
{
yield return(new IntRectangle(freeRect.X, itemRect.Bottom, freeRect.Width, hb));
}
var wr = freeRect.Right - itemRect.Right;
if (wr > 0)
{
yield return(new IntRectangle(itemRect.Right, freeRect.Top, wr, freeRect.Height));
}
var wl = itemRect.Left - freeRect.Left;
if (wl > 0)
{
yield return(new IntRectangle(freeRect.Left, freeRect.Top, wl, freeRect.Height));
}
}
/// <summary>
/// Rasterize a rectangular region.
/// </summary>
public static IEnumerable <IntVector> Rectangle(IntRectangle rect)
{
return(Rectangle(rect.X, rect.Y, rect.Width, rect.Height));
}
protected abstract bool Insert(IntSize size, out IntRectangle rectangle);
public bool TryGetRectangle(TElement element, out IntRectangle rectangle)
{
return(_elements.TryGetValue(element, out rectangle));
}
/// <inheritdoc/>
public bool TryGetRectangle(T element, out IntRectangle rectangle)
{
return(((IRectanglePacker <T>)_impl).TryGetRectangle(element, out rectangle));
}
