/// <summary>
/// Converts a given size of the x-axis to the amount of pixels required to display it.
/// </summary>
/// <param name="size">The size on the x-axis.</param>
/// <param name="intervals">The currently visible interval.</param>
/// <param name="panelSize">The amount of pixels within which the interval is shown.</param>
/// <returns></returns>
protected static double SizeToPixels(TXSize size, AxesIntervals <TX, TXSize, TY, TYSize> intervals, Size panelSize)
{
double intervalSize = Interval <TX, TXSize> .ConvertSizeToDouble(intervals.IntervalX.Size);
double requestedSize = Interval <TX, TXSize> .ConvertSizeToDouble(size);
return(panelSize.Width * (requestedSize / intervalSize));
}
/// <summary>
/// Converts a given amount of pixels to the equivalent size along the x-axis which that amount of pixels represents.
/// </summary>
/// <param name="pixels">The amount of pixels for which to know the size along the x-axis.</param>
/// <param name="intervals">The currently visible interval.</param>
/// <param name="panelSize">The amount of pixels within which the interval is shown.</param>
/// <returns></returns>
protected static TXSize PixelsToSize(double pixels, AxesIntervals <TX, TXSize, TY, TYSize> intervals, Size panelSize)
{
double intervalSize = Interval <TX, TXSize> .ConvertSizeToDouble(intervals.IntervalX.Size);
double size = (pixels / panelSize.Width) * intervalSize;
return(Interval <TX, TXSize> .ConvertDoubleToSize(size));
}
double IntervalSize <T, TSize>(Interval <T, TSize> visible, TSize desiredSize, double visiblePixels)
where T : IComparable <T>
where TSize : IComparable <TSize>
{
double intervalSize = Interval <T, TSize> .ConvertSizeToDouble(visible.Size);
double desired = Interval <T, TSize> .ConvertSizeToDouble(desiredSize);
return((desired / intervalSize) * visiblePixels);
}
public override void VisibleIntervalChanged(
AxesIntervals <TX, TXSize, TY, TYSize> visible,
AxesIntervals <TX, TXSize, TY, TYSize> limits,
Size panelSize)
{
// Create extended intervals.
Interval <TX, TXSize> intervalX = visible.IntervalX;
Interval <TY, TYSize> intervalY = visible.IntervalY;
Tuple <TXSize, TYSize> maxLabelSize = GetMaximumLabelSize(visible);
var additionalX = Operator <TXSize> .Add(maxLabelSize.Item1, maxLabelSize.Item1);
var additionalY = Operator <TYSize> .Add(maxLabelSize.Item2, maxLabelSize.Item2);
var extendedX = Operator <TXSize> .Add(intervalX.Size, additionalX);
var extendedY = Operator <TYSize> .Add(intervalY.Size, additionalY);
double scaleX = Interval <TX, TXSize> .ConvertSizeToDouble(extendedX) / Interval <TX, TXSize> .ConvertSizeToDouble(intervalX.Size);
double scaleY = Interval <TY, TYSize> .ConvertSizeToDouble(extendedY) / Interval <TY, TYSize> .ConvertSizeToDouble(intervalY.Size);
Interval <TX, TXSize> scaledX = intervalX.Scale(scaleX, limits.IntervalX);
Interval <TY, TYSize> scaledY = intervalY.Scale(scaleY, limits.IntervalY);
var extendedIntervals = new AxesIntervals <TX, TXSize, TY, TYSize>(scaledX, scaledY);
var toPosition = new HashSet <Tuple <TX, TY> >(GetPositions(extendedIntervals, panelSize));
// Free up labels which are no longer visible, and update those already positioned.
var toRemove = new List <PositionedElement>();
var toUpdate = new List <PositionedElement>();
foreach (var positioned in _visibleLabels)
{
if (toPosition.Contains(positioned.Position))
{
toUpdate.Add(positioned);
toPosition.Remove(positioned.Position);
}
else
{
Remove(positioned.Element);
_availableLabels.Push(positioned.Element);
toRemove.Add(positioned);
}
}
toRemove.ForEach(r => _visibleLabels.Remove(r));
// Position new labels.
var toInitialize = new List <PositionedElement>();
foreach (var position in toPosition)
{
// Create a new label when needed, or retrieve existing one.
FrameworkElement toPlace;
if (_availableLabels.Count == 0)
{
toPlace = CreateLabel();
toPlace.CacheMode = new BitmapCache();
}
else
{
toPlace = _availableLabels.Pop();
}
toPlace.SetValue(AxesPanel <TX, TXSize, TY, TYSize> .XProperty, position.Item1);
toPlace.SetValue(AxesPanel <TX, TXSize, TY, TYSize> .YProperty, position.Item2);
Add(toPlace);
var positioned = new PositionedElement(toPlace, position);
_visibleLabels.Add(positioned);
toInitialize.Add(positioned);
}
// Only update and initialize labels at end, so that _visibleLabels is up to date.
toInitialize.ForEach(i => InitializeLabel(i, visible, panelSize));
toUpdate.ForEach(u => UpdateLabel(u, visible, panelSize));
}