in src/Avalonia.Controls/TickBar.cs [213:399]
public sealed override void Render(DrawingContext dc)
{
var size = new Size(Bounds.Width, Bounds.Height);
var range = Maximum - Minimum;
var tickLen = 0.0d; // Height for Primary Tick (for Minimum and Maximum value)
var tickLen2 = 0.0d; // Height for Secondary Tick
var logicalToPhysical = 1.0;
var startPoint = new Point();
var endPoint = new Point();
var rSpace = Orientation == Orientation.Horizontal ? ReservedSpace.Width : ReservedSpace.Height;
// Take Thumb size in to account
double halfReservedSpace = rSpace * 0.5;
switch (Placement)
{
case TickBarPlacement.Top:
if (MathUtilities.GreaterThanOrClose(rSpace, size.Width))
{
return;
}
size = new Size(size.Width - rSpace, size.Height);
tickLen = -size.Height;
startPoint = new Point(halfReservedSpace, size.Height);
endPoint = new Point(halfReservedSpace + size.Width, size.Height);
logicalToPhysical = size.Width / range;
break;
case TickBarPlacement.Bottom:
if (MathUtilities.GreaterThanOrClose(rSpace, size.Width))
{
return;
}
size = new Size(size.Width - rSpace, size.Height);
tickLen = size.Height;
startPoint = new Point(halfReservedSpace, 0d);
endPoint = new Point(halfReservedSpace + size.Width, 0d);
logicalToPhysical = size.Width / range;
break;
case TickBarPlacement.Left:
if (MathUtilities.GreaterThanOrClose(rSpace, size.Height))
{
return;
}
size = new Size(size.Width, size.Height - rSpace);
tickLen = -size.Width;
startPoint = new Point(size.Width, size.Height + halfReservedSpace);
endPoint = new Point(size.Width, halfReservedSpace);
logicalToPhysical = size.Height / range * -1;
break;
case TickBarPlacement.Right:
if (MathUtilities.GreaterThanOrClose(rSpace, size.Height))
{
return;
}
size = new Size(size.Width, size.Height - rSpace);
tickLen = size.Width;
startPoint = new Point(0d, size.Height + halfReservedSpace);
endPoint = new Point(0d, halfReservedSpace);
logicalToPhysical = size.Height / range * -1;
break;
}
tickLen2 = tickLen * 0.75;
// Invert direction of the ticks
if (IsDirectionReversed)
{
logicalToPhysical *= -1;
// swap startPoint & endPoint
var pt = startPoint;
startPoint = endPoint;
endPoint = pt;
}
var pen = new ImmutablePen(Fill?.ToImmutable(), 1.0d);
// Is it Vertical?
if (Placement == TickBarPlacement.Left || Placement == TickBarPlacement.Right)
{
// Reduce tick interval if it is more than would be visible on the screen
double interval = TickFrequency;
if (interval > 0.0)
{
double minInterval = (Maximum - Minimum) / size.Height;
if (interval < minInterval)
{
interval = minInterval;
}
}
// Draw Min & Max tick
dc.DrawLine(pen, startPoint, new Point(startPoint.X + tickLen, startPoint.Y));
dc.DrawLine(pen, new Point(startPoint.X, endPoint.Y),
new Point(startPoint.X + tickLen, endPoint.Y));
// This property is rarely set so let's try to avoid the GetValue
// caching of the mutable default value
var ticks = Ticks ?? null;
// Draw ticks using specified Ticks collection
if (ticks?.Count > 0)
{
for (int i = 0; i < ticks.Count; i++)
{
if (MathUtilities.LessThanOrClose(ticks[i], Minimum) || MathUtilities.GreaterThanOrClose(ticks[i], Maximum))
{
continue;
}
double adjustedTick = ticks[i] - Minimum;
double y = adjustedTick * logicalToPhysical + startPoint.Y;
dc.DrawLine(pen,
new Point(startPoint.X, y),
new Point(startPoint.X + tickLen2, y));
}
}
// Draw ticks using specified TickFrequency
else if (interval > 0.0)
{
for (double i = interval; i < range; i += interval)
{
double y = i * logicalToPhysical + startPoint.Y;
dc.DrawLine(pen,
new Point(startPoint.X, y),
new Point(startPoint.X + tickLen2, y));
}
}
}
else // Placement == Top || Placement == Bottom
{
// Reduce tick interval if it is more than would be visible on the screen
double interval = TickFrequency;
if (interval > 0.0)
{
double minInterval = (Maximum - Minimum) / size.Width;
if (interval < minInterval)
{
interval = minInterval;
}
}
// Draw Min & Max tick
dc.DrawLine(pen, startPoint, new Point(startPoint.X, startPoint.Y + tickLen));
dc.DrawLine(pen, new Point(endPoint.X, startPoint.Y),
new Point(endPoint.X, startPoint.Y + tickLen));
// This property is rarely set so let's try to avoid the GetValue
// caching of the mutable default value
var ticks = Ticks ?? null;
// Draw ticks using specified Ticks collection
if (ticks?.Count > 0)
{
for (int i = 0; i < ticks.Count; i++)
{
if (MathUtilities.LessThanOrClose(ticks[i], Minimum) || MathUtilities.GreaterThanOrClose(ticks[i], Maximum))
{
continue;
}
double adjustedTick = ticks[i] - Minimum;
double x = adjustedTick * logicalToPhysical + startPoint.X;
dc.DrawLine(pen,
new Point(x, startPoint.Y),
new Point(x, startPoint.Y + tickLen2));
}
}
// Draw ticks using specified TickFrequency
else if (interval > 0.0)
{
for (double i = interval; i < range; i += interval)
{
double x = i * logicalToPhysical + startPoint.X;
dc.DrawLine(pen,
new Point(x, startPoint.Y),
new Point(x, startPoint.Y + tickLen2));
}
}
}
}