private void TrimToLiveScroll()
{
double scaleX = this.liveScrollingXScale;
this.visibleEndIndex = series.Values.Count;
this.visibleStartIndex = this.visibleEndIndex;
var width = this.ActualWidth;
// find the data value that starts the chart on the left side of the scrolling window
// and make this the visibleStartIndex from which smooth scrolling will resume.
if (series.Values.Count > 0)
{
// walk back until the scaled values fill one screen width.
this.visibleStartIndex = this.visibleEndIndex - 1;
var dv = series.Values[this.visibleStartIndex];
double endX = dv.X * scaleX;
while (--this.visibleStartIndex > 0)
{
dv = series.Values[this.visibleStartIndex];
double startX = dv.X * scaleX;
if (endX - startX > width)
{
break;
}
}
}
this.scaleSelf = null;
this.dirty = true;
}
public void Combine(ChartScaleInfo info)
{
minX = Math.Min(minX, info.minX);
maxX = Math.Max(maxX, info.maxX);
minY = Math.Min(minY, info.minY);
maxY = Math.Max(maxY, info.maxY);
}
internal bool ComputeScale(SimpleLineChart trigger)
{
bool changed = false;
ChartScaleInfo combined = null;
int index = this.scaleIndex;
// make sure they are all up to date.
foreach (var ptr in FindCharts())
{
ChartScaleInfo info = ptr.ComputeScaleSelf(index);
if (combined == null)
{
combined = info;
}
else
{
combined.Combine(info);
}
}
foreach (var ptr in FindCharts())
{
if (ptr.ApplyScale(combined))
{
if (ptr != trigger)
{
ptr.DelayedUpdate();
}
changed = true;
}
}
return(changed);
}
public ChartScaleInfo ComputeScaleSelf()
{
int startIndex = this.visibleStartIndex;
int endIndex = this.visibleEndIndex;
if (!dirty && scaleSelf != null && !this.liveScrolling)
{
return(scaleSelf);
}
if (scaleSelf != null && this.liveScrolling)
{
// try and do incremental update of the scale for added efficiency!
startIndex = this.smoothScrollScaleIndex;
}
else
{
scaleSelf = new ChartScaleInfo();
this.smoothScrollScaleIndex = 0;
}
if (series == null)
{
return(scaleSelf);
}
int len = series.Values.Count;
if (startIndex < 0)
{
startIndex = 0;
}
if (endIndex < 0 || endIndex > len)
{
endIndex = len;
}
if (this.ActualHeight == 0)
{
return(scaleSelf);
}
for (int i = startIndex; i < endIndex; i++)
{
DataValue d = series.Values[i];
double x = d.X;
double y = d.Y;
scaleSelf.Add(x, y);
}
this.smoothScrollScaleIndex = endIndex;
return(scaleSelf);
}
/// <summary>
/// Returns true if the scale just changed.
/// </summary>
bool ComputeScale()
{
bool changed = false;
if (this.Group != null && !scaleIndependently)
{
changed = this.Group.ComputeScale(this);
}
else
{
ChartScaleInfo info = ComputeScaleSelf(this.scaleIndex);
changed = ApplyScale(info);
}
return(changed);
}
public ChartScaleInfo ComputeScaleSelf(int index)
{
if (scaleSelf == null)
{
scaleSelf = new ChartScaleInfo();
}
if (!dirty)
{
return(scaleSelf);
}
if (index > 0)
{
// this is an incremental update then so we pick up where we left off.
}
else
{
// start over
scaleSelf = new ChartScaleInfo();
}
if (series == null)
{
return(scaleSelf);
}
int len = series.Values.Count;
if (index < 0)
{
index = 0;
}
for (int i = index; i < len; i++)
{
DataValue d = series.Values[i];
double x = d.X;
double y = d.Y;
scaleSelf.Add(x, y);
}
scaleIndex = len;
return(scaleSelf);
}
/// <summary>
/// Returns true if the scale just changed.
/// </summary>
bool ComputeScale()
{
bool changed = false;
if (this.Next != null)
{
ChartScaleInfo combined = null;
int index = this.scaleIndex;
// make sure they are all up to date.
foreach (var ptr in GroupItems)
{
ChartScaleInfo info = ptr.ComputeScaleSelf(index);
if (combined == null)
{
combined = info;
}
else
{
combined.Combine(info);
}
}
//Debug.WriteLine("Combined scale: minx={0}, maxx={1}, miny={2}, maxy={3}", combined.minX, combined.maxX, combined.minY, combined.maxY);
foreach (var ptr in GroupItems)
{
if (ptr.ApplyScale(combined))
{
if (ptr != this)
{
ptr.DelayedUpdate();
}
changed = true;
}
}
}
else
{
ChartScaleInfo info = ComputeScaleSelf(this.scaleIndex);
changed = ApplyScale(info);
}
return(changed);
}
internal bool ApplyScale(ChartScaleInfo info)
{
if (info == null)
{
return(false);
}
double actualHeight = this.ActualHeight - 1;
double actualWidth = this.ActualWidth;
bool changed = false;
this.minX = info.minX;
this.maxX = info.maxX;
this.minY = info.minY;
this.maxY = info.maxY;
double yRange = maxY - minY;
if (yRange == 0)
{
yRange = 1;
}
double newyScale = actualHeight / yRange;
if (newyScale == 0)
{
newyScale = 1;
}
if (newyScale != yScale)
{
yScale = newyScale;
changed = true;
}
// overrides for automatic X-Scaling.
if (fixedMaximumX.HasValue)
{
this.maxX = fixedMaximumX.Value;
}
if (fixedMinimumX.HasValue)
{
this.minX = fixedMinimumX.Value;
}
double newxScale = LiveScrollingXScale;
if (!LiveScrolling)
{
double xRange = maxX - minX;
if (xRange == 0)
{
xRange = 1;
}
newxScale = actualWidth / xRange;
if (newxScale == 0)
{
newxScale = 1;
}
}
if (newxScale != xScale)
{
xScale = newxScale;
changed = true;
}
if (changed || scaleTransform == null)
{
Matrix m = new Matrix();
m.Scale(xScale, yScale);
m.OffsetX = -minX * xScale;
m.OffsetY = -minY * yScale;
scaleTransform = new MatrixTransform(m);
}
return(changed);
}
