/// <summary>
/// 本规则判断椭圆(圆)的四个顶点,以及圆心与相关Position的关系;
/// </summary>
/// <param name="owner"></param>
/// <param name="position"></param>
/// <param name="canvasContext"></param>
/// <returns></returns>
protected override ISnapShape MatchSnapShape(Ellipse ellipse, Vector2D position, ICanvasContext canvasContext)
{
if (ellipse.Ellipse2D == null)
{
return(null);
}
var screenPosition = canvasContext.CanvasProxy.ToScreen(position);
var pointsPositions = new Vector2D[] {
ellipse.Ellipse2D.GetTopPoint(),
ellipse.Ellipse2D.GetBottomPoint(),
ellipse.Ellipse2D.GetLeftPoint(),
ellipse.Ellipse2D.GetRightPoint(),
ellipse.Ellipse2D.Center
};
var screenPoint = new Vector2D();
foreach (var pointPosition in pointsPositions)
{
canvasContext.CanvasProxy.ToScreen(pointPosition, screenPoint);
var screenRect = NativeGeometryExtensions.GetNativeSuroundingScreenRect(
screenPoint,
TolerantedScreenLength,
TolerantedScreenLength
);
if (screenRect.Contains(screenPosition))
{
return(new StandardSnapPoint(pointPosition));
}
}
return(null);
}
/// <summary>
/// 绘制选择状态;
/// </summary>
/// <param name="canvas"></param>
/// <param name="canvasProxy"></param>
private void DrawSelectedState(ICanvas canvas, ICanvasScreenConvertable canvasProxy)
{
if (!IsSelected)
{
return;
}
if (Rectangle2D == null)
{
return;
}
//绘制四边的中点;
var lines = Rectangle2D.GetLines();
var rectLength = TolerantedScreenLength;
foreach (var line in lines)
{
var point = line.MiddlePoint;
var rect = NativeGeometryExtensions.GetNativeSuroundingScreenRect(canvasProxy.ToScreen(point), rectLength, rectLength);
canvas.NativeDrawRectangle(rect, HighLightEllipseColorBrush, HighLightLinePen);
}
//绘制中心;
var centerPointX = Rectangle2D.GetVertexes().Average(p => p.X);
var centerPointY = Rectangle2D.GetVertexes().Average(p => p.Y);
var centerScreenPoint = canvasProxy.ToScreen(new Vector2D(centerPointX, centerPointY));
var centerRect = NativeGeometryExtensions.GetNativeSuroundingScreenRect(centerScreenPoint, rectLength, rectLength);
canvas.NativeDrawRectangle(centerRect, HighLightEllipseColorBrush, HighLightLinePen);
}
public override void Draw(ICanvas canvas, ICanvasScreenConvertable canvasProxy)
{
var screenPosition = canvasProxy.ToScreen(Position);
var rectLength = HighLightRectLength;
var rect = NativeGeometryExtensions.GetNativeSuroundingScreenRect(screenPosition, rectLength, rectLength);
canvas.NativeDrawRectangle(rect, Background, LinePen);
}
public override bool PointInObject(Vector2D point, ICanvasScreenConvertable canvasProxy)
{
if (point == null)
{
throw new ArgumentNullException(nameof(point));
}
if (canvasProxy == null)
{
throw new ArgumentNullException(nameof(canvasProxy));
}
if (Ellipse2D == null)
{
return(false);
}
#if DEBUG
#endif
//判断是否与圆心有关系;
var centerScreenPosition = canvasProxy.ToScreen(Ellipse2D.Center);
var centerScreenRect = NativeGeometryExtensions.GetNativeSuroundingScreenRect(
centerScreenPosition,
TolerantedScreenLength,
TolerantedScreenLength
);
if (centerScreenRect.Contains(canvasProxy.ToScreen(point)))
{
return(true);
}
//若是圆,则通过点到圆心的距离判断;
if (Ellipse2D.RadiusX == Ellipse2D.RadiusY)
{
var screenDis = canvasProxy.ToScreen(Ellipse2D.Center.Distance(point));
var screenRadius = canvasProxy.ToScreen(Ellipse2D.RadiusX);
//若半径小于误差值,则判断距离是否小于误差值;
if (screenRadius < TolerantedScreenLength)
{
return(screenDis < TolerantedScreenLength);
}
//判断是否处于圆周上;
else
{
return(screenDis > screenRadius - TolerantedScreenLength &&
screenDis < screenRadius + TolerantedScreenLength);
}
}
//To-Do,椭圆,未完成;
else
{
return(Ellipse2D.Contains(point));
}
}
public ISnapShape MatchSnapShape(DrawObject[] drawObjects, Vector2D position, ICanvasContext canvasContext)
{
if (drawObjects == null)
{
return(null);
}
#if DEBUG
//position = new Vector2D(0, 0);
#endif
var screenPosition = canvasContext.CanvasProxy.ToScreen(position);
var rect = Rectangle2D2.CreateEmpty();
//双游标两两遍历;
for (int i = 0; i < drawObjects.Length - 1; i++)
{
for (int j = i + 1; j < drawObjects.Length; j++)
{
var intersectPositions = DrawObjectIntersectRule.GetIntersectPositions(drawObjects[i], drawObjects[j]);
if (intersectPositions == null)
{
continue;
}
foreach (var intersectPosition in intersectPositions)
{
NativeGeometryExtensions.GetNativeSuroundingScreenRect(
canvasContext.CanvasProxy.ToScreen(intersectPosition),
TolerantedScreenLength,
TolerantedScreenLength,
rect
);
if (rect.Contains(screenPosition))
{
return(new IntersectSnapPoint(intersectPosition));
}
}
}
}
return(null);
}
public override Rectangle2D2 GetNativeBoundingRect(ICanvasScreenConvertable canvasProxy)
{
if (canvasProxy == null)
{
throw new ArgumentNullException(nameof(canvasProxy));
}
var screenPosition = canvasProxy.ToScreen(Position);
var rect = NativeGeometryExtensions.GetNativeSuroundingScreenRect(
screenPosition,
HighLightRectLength,
HighLightRectLength
);
return(rect);
}
public ISnapShape MatchSnapShape(DrawObject[] drawObjects, Vector2D position, ICanvasContext canvasContext)
{
if (position == null)
{
throw new ArgumentNullException(nameof(position));
}
if (canvasContext == null)
{
throw new ArgumentNullException(nameof(canvasContext));
}
//若当前网格的视图长度过小,可能画布缩放比例过大,不能匹配;
var screenUnitLength = canvasContext.CanvasProxy.ToScreen(1);
if (screenUnitLength < TolerantedScreenLength * 2)
{
return(null);
}
var screenPosition = canvasContext.CanvasProxy.ToScreen(position);
int gridX = (int)Math.Round(position.X);
int gridY = (int)Math.Round(position.Y);
var gridPointPosition = new Vector2D(gridX, gridY);
var gridPointScreenPosition = canvasContext.CanvasProxy.ToScreen(gridPointPosition);
var screenRect = NativeGeometryExtensions.GetNativeSuroundingScreenRect(
gridPointScreenPosition,
TolerantedScreenLength, TolerantedScreenLength
);
if (screenRect.Contains(screenPosition))
{
return(new StandardSnapPoint(gridPointPosition));
}
return(null);
}
public override void Draw(ICanvas canvas, ICanvasScreenConvertable canvasProxy)
{
base.Draw(canvas, canvasProxy);
//检查两个关键位置是否为空;
if (MousePositionTracker.LastMouseDownPosition == null || MousePositionTracker.CurrentHoverPosition == null)
{
return;
}
//绘制当前随鼠标位置移动的编辑线段;
//绘制本次尚未完成的线段的起始点小正方形;
var lastMouseDownScreenPosition = canvasProxy.ToScreen(MousePositionTracker.LastMouseDownPosition);
var sideLength = HighLightRectLength;
var startEditRect = NativeGeometryExtensions.GetNativeSuroundingScreenRect(lastMouseDownScreenPosition, sideLength, sideLength);
canvas.NativeDrawRectangle(startEditRect, HighLightRectColorBrush, LinePen);
//在外部加入了动态输入,此时显示线段编辑状态多余;
//DrawEditingLineState(canvas, canvasProxy);
}
/// <summary>
/// 绘制选择状态;
/// </summary>
/// <param name="canvas"></param>
private void DrawSelectedState(ICanvas canvas, ICanvasScreenConvertable canvasProxy)
{
if (!IsSelected)
{
return;
}
if (Ellipse2D == null)
{
return;
}
if (Ellipse2D.Center == null)
{
return;
}
var centerScreenPoint = canvasProxy.ToScreen(Ellipse2D.Center);
var screenRadiusX = canvasProxy.ToScreen(Ellipse2D.RadiusX);
var screenRadiusY = canvasProxy.ToScreen(Ellipse2D.RadiusY);
var rectLength = TolerantedScreenLength;
//依次绘制左、下、右、上、圆心的矩形;
var points = new Vector2D[] {
new Vector2D(centerScreenPoint.X - screenRadiusX, centerScreenPoint.Y),
new Vector2D(centerScreenPoint.X, centerScreenPoint.Y - screenRadiusY),
new Vector2D(centerScreenPoint.X + screenRadiusX, centerScreenPoint.Y),
new Vector2D(centerScreenPoint.X, centerScreenPoint.Y + screenRadiusY),
new Vector2D(centerScreenPoint.X, centerScreenPoint.Y),
};
foreach (var point in points)
{
var rect = NativeGeometryExtensions.GetNativeSuroundingScreenRect(point, rectLength, rectLength);
canvas.NativeDrawRectangle(rect, HighLightEllipseColorBrush, HighLightLinePen);
}
}
