protected override void OnPaint(PaintEventArgs e)
{
int height = ClientSize.Height;
int pixelsPerHour = (PixelsPerHour * (_Scrollable ? ZoomRatio : 128)) / 128;
long maxValue = MaximumThreshold;
long minTicks = 0, maxTicks = 0;
int contentWidth;
const long hourInTicks = Squared.Util.Time.SecondInTicks * 60 * 60;
if (Items.Count > 0)
{
maxValue = Math.Max(MaximumThreshold, (from s in Items select _ItemValueGetter(s)).Max());
minTicks = (from s in Items select s.Timestamp.Ticks).Min();
maxTicks = (from s in Items select s.Timestamp.Ticks).Max();
bool rescaled = false;
rescale:
_ContentWidth = contentWidth = (int)(
(maxTicks - minTicks)
* pixelsPerHour / hourInTicks
) + MarginWidth;
if (!_Scrollable && !rescaled)
{
var ratio = (ClientSize.Width / (double)(contentWidth + 1)) * 128.0;
_ZoomRatio = (int)Math.Floor(ratio);
if (_ZoomRatio < 1)
{
_ZoomRatio = 1;
}
pixelsPerHour = (PixelsPerHour * _ZoomRatio) / 128;
if (pixelsPerHour < 1)
{
pixelsPerHour = 1;
}
rescaled = true;
goto rescale;
}
}
else
{
_ContentWidth = contentWidth = MarginWidth;
}
if (_Scrollable)
{
height -= ScrollBar.Height;
if (_ScrollOffset > contentWidth - ClientSize.Width)
{
_ScrollOffset = contentWidth - ClientSize.Width;
}
if (_ScrollOffset < 0)
{
_ScrollOffset = 0;
}
int scrollMax = contentWidth - ClientSize.Width + ScrollBar.LargeChange - 1;
bool enabled = (scrollMax > 0);
if (scrollMax < 0)
{
scrollMax = 0;
}
// WinForms' scrollbar control is terrible
if (ScrollBar.Maximum != scrollMax)
{
ScrollBar.Maximum = scrollMax;
}
if (ScrollBar.Value != _ScrollOffset)
{
ScrollBar.Value = _ScrollOffset;
}
if (ScrollBar.Enabled != enabled)
{
ScrollBar.Enabled = enabled;
}
if (!ScrollBar.Visible)
{
ScrollBar.Visible = true;
}
if (!ZoomInButton.Visible)
{
ZoomInButton.Visible = true;
}
if (!ZoomOutButton.Visible)
{
ZoomOutButton.Visible = true;
}
}
else
{
if (ScrollBar.Visible)
{
ScrollBar.Visible = false;
}
if (ZoomInButton.Visible)
{
ZoomInButton.Visible = false;
}
if (ZoomOutButton.Visible)
{
ZoomOutButton.Visible = false;
}
_ScrollOffset = 0;
}
using (var outlinePen = new Pen(Color.Black))
using (var gridPen = new Pen(Color.FromArgb(96, 0, 0, 0)))
using (var scratch = Scratch.Get(e.Graphics, ClientRectangle)) {
var g = scratch.Graphics;
g.Clear(BackColor);
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
float y = 0;
using (var textBrush = new SolidBrush(ForeColor))
{
g.DrawLine(gridPen, 0, height - VerticalMargin, ClientSize.Width, height - VerticalMargin);
g.DrawLine(gridPen, 0, VerticalMargin, Width, VerticalMargin);
var lineHeight = g.MeasureString("AaBbYyZz", Font).Height;
var numLines = (int)Math.Min(
Math.Max(2, Math.Floor((height / lineHeight) * GridLineRatio)),
MaxGridLines
);
for (int i = 0; i <= numLines; i++)
{
var value = (maxValue * i / numLines);
var text = _ItemValueFormatter(value);
y = (float)(height - VerticalMargin - ((value / (double)maxValue) * (height - VerticalMargin * 2)));
g.DrawLine(gridPen, 0, y, ClientSize.Width, y);
g.DrawString(text, Font, textBrush, new PointF(4, y));
}
}
var itemXCoordinates = (from item in Items
select
(int)((item.Timestamp.Ticks - minTicks)
* pixelsPerHour / hourInTicks
) - _ScrollOffset).ToArray();
var itemYCoordinates = (from item in Items
select
(float)(height - VerticalMargin - (
(_ItemValueGetter(item) / (double)maxValue) *
(height - VerticalMargin * 2)
)));
var valueSeriesYCoordinates = (
from series in DataSeries.Values
select(
from value in series
select
(float)(height - VerticalMargin - (
(value / (double)maxValue) *
(height - VerticalMargin * 2)
))
)
);
var firstIndex = Math.Max(0, IndexFromPoint(new Point(0, 0), -1));
using (var brush = new SolidBrush(Color.FromArgb(127, ForeColor)))
DrawValueSeries(
g,
itemXCoordinates.Skip(firstIndex),
itemYCoordinates.Skip(firstIndex),
ClientSize.Width, height,
brush, outlinePen
);
int seriesIndex = 0;
foreach (var series in valueSeriesYCoordinates)
{
int hue = (HSV.HueMax * seriesIndex) / DataSeries.Count;
var seriesColor = HSV.ColorFromHSV(
(UInt16)hue, HSV.SaturationMax, HSV.ValueMax
);
using (var brush = new SolidBrush(Color.FromArgb(15, seriesColor)))
using (var pen = new Pen(Color.FromArgb(160, seriesColor)))
DrawValueSeries(
g, itemXCoordinates.Skip(firstIndex),
series.Skip(firstIndex),
ClientSize.Width, height,
brush, pen
);
seriesIndex += 1;
}
firstIndex = Selection.First;
var takeCount = Selection.Second - Selection.First + 1;
using (var brush = new SolidBrush(SystemColors.Highlight))
using (var pen = new Pen(SystemColors.HighlightText)
{
Width = 2.0f
})
DrawValueSeries(
g,
itemXCoordinates.Skip(firstIndex).Take(takeCount),
itemYCoordinates.Skip(firstIndex).Take(takeCount),
ClientSize.Width, height,
brush, pen
);
var cursorPos = PointToClient(Cursor.Position);
DateTime mouseTime;
if (ClientRectangle.Contains(cursorPos) && TimeFromPoint(_MouseMoveLocation, out mouseTime))
{
using (var pen = new Pen(Color.FromArgb(127, SystemColors.HighlightText))) {
pen.Width = 2.0f;
g.DrawLine(pen, _MouseMoveLocation.X, 0, _MouseMoveLocation.X, height);
}
var mouseIndex = IndexFromTime(mouseTime, -1);
if (!_MouseDownLocation.HasValue)
{
using (var pen = new Pen(SystemColors.HighlightText)) {
pen.Width = 2.0f;
var item = Items[mouseIndex];
var x = (int)((item.Timestamp.Ticks - minTicks) * pixelsPerHour / hourInTicks) - _ScrollOffset;
g.DrawLine(
pen,
x, 0, x, height
);
}
}
}
}
}