/// <summary>
/// Helper function, which draws a screw on the frame
/// </summary>
/// <param name="graph">Chart graphics to use.</param>
/// <param name="rect">Screw position.</param>
private void DrawScrew(ChartGraphics graph, SKRect rect)
{
// Draw screw
SKPaint screwPen = new() { Color = Color.FromArgb(128, 255, 255, 255), StrokeWidth = 1, Style = SKPaintStyle.Stroke };
graph.DrawEllipse(screwPen, rect.Left, rect.Top, rect.Width, rect.Height);
graph.DrawLine(screwPen, rect.Left + 2 * resolution / 96.0f, rect.Top + rect.Height - 2 * resolution / 96.0f, rect.Right - 2 * resolution / 96.0f, rect.Top + 2 * resolution / 96.0f);
screwPen.Color = Color.FromArgb(128, SKColors.Black);
graph.DrawEllipse(screwPen, rect.Left + 1 * resolution / 96.0f, rect.Top + 1 * resolution / 96.0f, rect.Width, rect.Height);
graph.DrawLine(screwPen, rect.Left + 3 * resolution / 96.0f, rect.Top + rect.Height - 1 * resolution / 96.0f, rect.Right - 1 * resolution / 96.0f, rect.Top + 3 * resolution / 96.0f);
}
#endregion Border properties and methods
}
/// <summary>
/// Draws 3D button in the scroll bar
/// </summary>
/// <param name="graph">Chart graphics.</param>
/// <param name="buttonRect">Button position.</param>
/// <param name="pressedState">Indicates that button is pressed.</param>
/// <param name="buttonType">Button type to draw.</param>
internal void PaintScrollBar3DButton(
ChartGraphics graph,
SKRect buttonRect,
bool pressedState,
ScrollBarButtonType buttonType)
{
// Page Up/Down buttons do not require drawing
if (buttonType == ScrollBarButtonType.LargeIncrement || buttonType == ScrollBarButtonType.LargeDecrement)
{
return;
}
// Get 3 levels of colors for button drawing
var darkerColor = ChartGraphics.GetGradientColor(_buttonCurrentColor, SKColors.Black, 0.5);
var darkestColor = ChartGraphics.GetGradientColor(_buttonCurrentColor, SKColors.Black, 0.8);
var lighterColor = ChartGraphics.GetGradientColor(_buttonCurrentColor, SKColors.White, 0.5);
// Fill button rectangle background
graph.FillRectangleRel(
buttonRect,
_buttonCurrentColor,
ChartHatchStyle.None,
"",
ChartImageWrapMode.Tile,
SKColor.Empty,
ChartImageAlignmentStyle.Center,
GradientStyle.None,
SKColor.Empty,
darkerColor,
(pressedState) ? 1 : 0,
ChartDashStyle.Solid,
SKColor.Empty,
0,
PenAlignment.Outset);
// Check if 2 or 1 pixel border will be drawn (if size too small)
bool singlePixelBorder = Size <= 12;
// Draw 3D effect around the button when not pressed
if (!pressedState)
{
// Get relative size of 1 pixel
SKSize pixelRelativeSize = new(1, 1);
pixelRelativeSize = graph.GetRelativeSize(pixelRelativeSize);
// Draw top/left border with button color
graph.DrawLineRel(
(singlePixelBorder) ? lighterColor : _buttonCurrentColor, 1, ChartDashStyle.Solid,
new SKPoint(buttonRect.Left, buttonRect.Bottom),
new SKPoint(buttonRect.Left, buttonRect.Top));
graph.DrawLineRel(
(singlePixelBorder) ? lighterColor : _buttonCurrentColor, 1, ChartDashStyle.Solid,
new SKPoint(buttonRect.Left, buttonRect.Top),
new SKPoint(buttonRect.Right, buttonRect.Top));
// Draw right/bottom border with the darkest color
graph.DrawLineRel(
(singlePixelBorder) ? darkerColor : darkestColor, 1, ChartDashStyle.Solid,
new SKPoint(buttonRect.Right, buttonRect.Bottom),
new SKPoint(buttonRect.Right, buttonRect.Top));
graph.DrawLineRel(
(singlePixelBorder) ? darkerColor : darkestColor, 1, ChartDashStyle.Solid,
new SKPoint(buttonRect.Left, buttonRect.Bottom),
new SKPoint(buttonRect.Right, buttonRect.Bottom));
if (!singlePixelBorder)
{
// Draw right/bottom border (offset 1) with the dark color
graph.DrawLineRel(
darkerColor, 1, ChartDashStyle.Solid,
new SKPoint(buttonRect.Right - pixelRelativeSize.Width, buttonRect.Bottom - pixelRelativeSize.Height),
new SKPoint(buttonRect.Right - pixelRelativeSize.Width, buttonRect.Top + pixelRelativeSize.Height));
graph.DrawLineRel(
darkerColor, 1, ChartDashStyle.Solid,
new SKPoint(buttonRect.Left + pixelRelativeSize.Width, buttonRect.Bottom - pixelRelativeSize.Height),
new SKPoint(buttonRect.Right - pixelRelativeSize.Width, buttonRect.Bottom - pixelRelativeSize.Height));
// Draw top/left border (offset 1) with lighter color
graph.DrawLineRel(
lighterColor, 1, ChartDashStyle.Solid,
new SKPoint(buttonRect.Left + pixelRelativeSize.Width, buttonRect.Bottom - pixelRelativeSize.Height),
new SKPoint(buttonRect.Left + pixelRelativeSize.Width, buttonRect.Top + pixelRelativeSize.Height));
graph.DrawLineRel(
lighterColor, 1, ChartDashStyle.Solid,
new SKPoint(buttonRect.Left + pixelRelativeSize.Width, buttonRect.Left + pixelRelativeSize.Height),
new SKPoint(buttonRect.Right - pixelRelativeSize.Width, buttonRect.Left + pixelRelativeSize.Height));
}
}
// Check axis orientation
bool verticalAxis = (axis.AxisPosition == AxisPosition.Left ||
axis.AxisPosition == AxisPosition.Right);
// Set graphics transformation for button pressed mode
float pressedShifting = (singlePixelBorder) ? 0.5f : 1f;
if (pressedState)
{
graph.TranslateTransform(pressedShifting, pressedShifting);
}
// Draw button image
SKRect buttonAbsRect = graph.GetAbsoluteRectangle(buttonRect);
float imageOffset = (singlePixelBorder) ? 2 : 3;
switch (buttonType)
{
case (ScrollBarButtonType.SmallDecrement):
{
// Calculate triangal points position
SKPoint[] points = new SKPoint[3];
if (verticalAxis)
{
points[0].X = buttonAbsRect.Left + imageOffset;
points[0].Y = buttonAbsRect.Top + (imageOffset + 1f);
points[1].X = buttonAbsRect.Left + buttonAbsRect.Width / 2f;
points[1].Y = buttonAbsRect.Bottom - imageOffset;
points[2].X = buttonAbsRect.Right - imageOffset;
points[2].Y = buttonAbsRect.Top + (imageOffset + 1f);
}
else
{
points[0].X = buttonAbsRect.Left + imageOffset;
points[0].Y = buttonAbsRect.Top + buttonAbsRect.Height / 2f;
points[1].X = buttonAbsRect.Right - (imageOffset + 1f);
points[1].Y = buttonAbsRect.Top + imageOffset;
points[2].X = buttonAbsRect.Right - (imageOffset + 1f);
points[2].Y = buttonAbsRect.Bottom - imageOffset;
}
using var brush = new SKPaint { Style = SKPaintStyle.Fill, Color = _lineCurrentColor };
graph.FillPolygon(brush, points);
break;
}
case (ScrollBarButtonType.SmallIncrement):
{
// Calculate triangal points position
SKPoint[] points = new SKPoint[3];
if (verticalAxis)
{
points[0].X = buttonAbsRect.Left + imageOffset;
points[0].Y = buttonAbsRect.Bottom - (imageOffset + 1f);
points[1].X = buttonAbsRect.Left + buttonAbsRect.Width / 2f;
points[1].Y = buttonAbsRect.Top + imageOffset;
points[2].X = buttonAbsRect.Right - imageOffset;
points[2].Y = buttonAbsRect.Bottom - (imageOffset + 1f);
}
else
{
points[0].X = buttonAbsRect.Right - imageOffset;
points[0].Y = buttonAbsRect.Top + buttonAbsRect.Height / 2f;
points[1].X = buttonAbsRect.Left + (imageOffset + 1f);
points[1].Y = buttonAbsRect.Top + imageOffset;
points[2].X = buttonAbsRect.Left + (imageOffset + 1f);
points[2].Y = buttonAbsRect.Bottom - imageOffset;
}
using var brush = new SKPaint { Style = SKPaintStyle.Fill, Color = _lineCurrentColor };
graph.FillPolygon(brush, points);
break;
}
case (ScrollBarButtonType.ZoomReset):
{
// Draw circule with a minus sign
using var pen = new SKPaint { Style = SKPaintStyle.Fill, Color = _lineCurrentColor };
graph.DrawEllipse(pen, buttonAbsRect.Left + imageOffset - 0.5f, buttonAbsRect.Top + imageOffset - 0.5f, buttonAbsRect.Width - 2f * imageOffset, buttonAbsRect.Height - 2f * imageOffset);
graph.DrawLine(pen, buttonAbsRect.Left + imageOffset + 1.5f, buttonAbsRect.Top + buttonAbsRect.Height / 2f - 0.5f, buttonAbsRect.Right - imageOffset - 2.5f, buttonAbsRect.Top + buttonAbsRect.Height / 2f - 0.5f);
break;
}
}
// Reset graphics transformation for button pressed mode
if (pressedState)
{
graph.TranslateTransform(-pressedShifting, -pressedShifting);
}
}