protected override void OnMouseUp(
MouseEventArgs e)
{
if (_draggedPoint == null)
{
// add new point in specified position
Rectangle gradientRect = GetGradientRect();
if (e.X >= gradientRect.Left && e.X <= gradientRect.Right)
{
//
float pos = Math.Min(1f, (e.X - gradientRect.Left) / (float)gradientRect.Width);
int i;
for (i = 0; i < _gradientPoints.Count && _gradientPoints[i].Position <= pos; i++)
{
;
}
//
AddPoint(i, i == 0 ? pos : pos - _gradientPoints[i - 1].Position);
}
}
else
{
_draggedPoint = null;
}
base.OnMouseUp(e);
}
private Color GetPointColor(
GradientPoint gp,
Bitmap bmp)
{
return(_gradientType == GradientType.InterpolationColors
? gp.Color
: bmp.GetPixel((int)Math.Round((bmp.Width - 1) * gp.Position), 0));
}
protected virtual void OnPointChanged(
GradientPoint point)
{
if (PointChanged != null)
{
PointChanged(this, new GradientPointEventArgs(point));
}
}
protected override void OnMouseDown(
MouseEventArgs e)
{
HitTestInfo hti = HitTest(e.X, e.Y);
if (hti.Point != null)
{
_draggedPoint = hti.Point;
HighlightedItem = hti.Point;
SelectedPoint = hti.Point;
OnSelectedPointChanged();
}
Focus();
base.OnMouseDown(e);
}
private PointState GetPointState(
GradientPoint point)
{
var result = PointState.None;
if (point == _selectedPoint)
{
result |= PointState.Selected;
}
if (point == _highlightedPoint)
{
result |= PointState.Highlighted;
}
return(result);
}
private Rectangle GetPointRect(
GradientPoint point,
PointState state,
Rectangle gradientRect)
{
var result = new Rectangle(
gradientRect.Left + (int)Math.Round(gradientRect.Width * point.Position) - c_MarkWidth / 2,
Padding.Top + 2,
c_MarkWidth,
ClientSize.Height - Padding.Top - Padding.Bottom - 2 - 2);
if (state != PointState.None)
{
result.Inflate(2, 2);
}
return(result);
}
public GradientPointsControl()
{
SetStyle(ControlStyles.UserPaint, true);
SetStyle(ControlStyles.AllPaintingInWmPaint, true);
SetStyle(ControlStyles.ResizeRedraw, true);
SetStyle(ControlStyles.Opaque, true);
SetStyle(ControlStyles.Selectable, true);
SetStyle(ControlStyles.DoubleBuffer, true);
_gradientPoints = new GradientPointCollection(this);
ResetGradientPoints();
_startColor = c_DefStartColor;
_endColor = c_DefEndColor;
Padding = c_DefPadding;
_selectedPoint = _gradientPoints[0];
}
private GradientPoint AddPoint(
int index,
float posRelativeToLeftPoint)
{
_internalChanges = true;
var gp = new GradientPoint();
if (index == 0)
{
gp.Position = posRelativeToLeftPoint;
gp.Factor = posRelativeToLeftPoint;
gp.Color = _gradientPoints[0].Color;
}
else if (index >= _gradientPoints.Count)
{
gp.Position = _gradientPoints[_gradientPoints.Count - 1].Position + posRelativeToLeftPoint;
gp.Factor = _gradientPoints[_gradientPoints.Count - 1].Factor + posRelativeToLeftPoint / (1 - _gradientPoints[_gradientPoints.Count - 1].Position) * (1 - _gradientPoints[_gradientPoints.Count - 1].Factor);
gp.Color = _gradientPoints[_gradientPoints.Count - 1].Color;
}
else
{
gp.Position = _gradientPoints[index - 1].Position + posRelativeToLeftPoint;
gp.Factor = _gradientPoints[index - 1].Factor + posRelativeToLeftPoint / (_gradientPoints[index].Position - _gradientPoints[index - 1].Position) * (_gradientPoints[index].Factor - _gradientPoints[index - 1].Factor);
gp.Color = GetMixedColor(
_gradientPoints[index - 1].Color,
_gradientPoints[index].Color,
posRelativeToLeftPoint / (_gradientPoints[index].Position - _gradientPoints[index - 1].Position));
}
_gradientPoints.Insert(index, gp);
_internalChanges = false;
SelectedPoint = gp;
HighlightedItem = gp;
Invalidate(GetPointRect(gp, GetGradientRect()));
OnPointAdded(gp);
OnSelectedPointChanged();
return(gp);
}
/// <summary>
/// Adds new <see cref="GradientPoint"/> after currently selected point.
/// </summary>
/// <returns></returns>
public GradientPoint AddPoint()
{
GradientPoint gp = SelectedPoint;
if (gp == null)
{
return(null);
}
int index = GradientPoints.IndexOf(gp);
if (index == 0)
{
return(AddPoint(index + 1, (GradientPoints[index + 1].Position - gp.Position) / 2));
}
if (index >= GradientPoints.Count - 1)
{
return(AddPoint(index, (gp.Position - GradientPoints[index - 1].Position) / 2));
}
return(AddPoint(index + 1, (GradientPoints[index + 1].Position - gp.Position) / 2));
}
private Rectangle GetPointRect(
GradientPoint point,
Rectangle gradientRect)
{
return(GetPointRect(point, GetPointState(point), gradientRect));
}
public GradientPointEventArgs(
GradientPoint point)
{
_point = point;
}
public HitTestInfo(
GradientPoint point)
{
_area = HitTestArea.Point;
_point = point;
}
public HitTestInfo(
HitTestArea area)
{
_area = area;
_point = null;
}