www.pudn.com > cad-draw.zip > LinesMeetEditTool.cs, change:2007-12-17,size:4701b

using System; 
using System.Collections.Generic; 
using System.Text; 
using System.Windows.Forms; 
 
namespace Canvas.EditTools 
{ 
	class LinePoints 
	{ 
		DrawTools.Line	m_line; 
		UnitPoint		m_p1; 
		UnitPoint		m_p2; 
		public UnitPoint MousePoint; 
		public DrawTools.Line Line 
		{ 
			get { return m_line; } 
		} 
		public void SetLine(DrawTools.Line l) 
		{ 
			m_line = l; 
			m_p1 = l.P1; 
			m_p2 = l.P2; 
		} 
		public void ResetLine() 
		{ 
			m_line.P1 = m_p1; 
			m_line.P2 = m_p2; 
		} 
		public void SetNewPoints(DrawTools.Line l, UnitPoint hitpoint, UnitPoint intersectpoint) 
		{ 
			SetLine(l); 
			double hitToVp1 = HitUtil.Distance(hitpoint, l.P1); // hit point to vertex point 
			double ispToVp1 = HitUtil.Distance(intersectpoint, l.P1); // intersect point to vertex point 
			// if hit is closer than intersect point, then keep this point and adjust the other 
			if (hitToVp1 <= ispToVp1) 
				m_p2 = intersectpoint; 
			else 
				m_p1 = intersectpoint; 
			ResetLine(); 
		} 
	} 
	class LinesMeetEditTool : IEditTool 
	{ 
		IEditToolOwner m_owner; 
		public LinesMeetEditTool(IEditToolOwner owner) 
		{ 
			m_owner = owner; 
			SetHint("Select first line"); 
		} 
		void SetHint(string text) 
		{ 
			if (m_owner != null) 
			{ 
				if (text.Length > 0) 
					m_owner.SetHint("Lines Meet: " + text); 
				else 
					m_owner.SetHint(""); 
			} 
		} 
		public IEditTool Clone() 
		{ 
			LinesMeetEditTool t = new LinesMeetEditTool(m_owner); 
			// nothing that needs to be cloned 
			return t; 
		} 
		LinePoints m_l1Original = new LinePoints(); 
		LinePoints m_l2Original = new LinePoints(); 
		LinePoints m_l1NewPoint = new LinePoints(); 
		LinePoints m_l2NewPoint = new LinePoints(); 
 
		public bool SupportSelection  
		{  
			get { return false; }  
		} 
		public void SetHitObjects(UnitPoint point, List<IDrawObject> list) 
		{ 
		} 
		public void OnMouseMove(ICanvas canvas, UnitPoint point) 
		{ 
		} 
		public eDrawObjectMouseDown OnMouseDown(ICanvas canvas, UnitPoint point, ISnapPoint snappoint) 
		{ 
			List<IDrawObject> items = canvas.DataModel.GetHitObjects(canvas, point); 
			DrawTools.Line line = null; 
			// find first line 
			foreach (IDrawObject item in items) 
			{ 
				if (item is DrawTools.Line) 
				{ 
					line = item as DrawTools.Line; 
					if (line != m_l1Original.Line) 
						break; 
				} 
			} 
			if (line == null) 
			{ 
				if (m_l1Original.Line == null) 
					SetHint("No line selected. Select first line"); 
				else 
					SetHint("No line selected. Select second line"); 
				return eDrawObjectMouseDown.Continue; 
			} 
			if (m_l1Original.Line == null) 
			{ 
				line.Highlighted = true; 
				m_l1Original.SetLine(line); 
				m_l1Original.MousePoint = point; 
				SetHint("Select second line"); 
				return eDrawObjectMouseDown.Continue; 
			} 
			if (m_l2Original.Line == null) 
			{ 
				line.Highlighted = true; 
				m_l2Original.SetLine(line); 
				m_l2Original.MousePoint = point; 
 
				UnitPoint intersectpoint = HitUtil.LinesIntersectPoint( 
					m_l1Original.Line.P1,  
					m_l1Original.Line.P2,  
					m_l2Original.Line.P1,  
					m_l2Original.Line.P2); 
				 
				// if lines do not intersect then extend lines to intersect point 
				if (intersectpoint == UnitPoint.Empty) 
				{ 
					UnitPoint apprarentISPoint = HitUtil.FindApparentIntersectPoint(m_l1Original.Line.P1, m_l1Original.Line.P2, m_l2Original.Line.P1, m_l2Original.Line.P2); 
					if (apprarentISPoint == UnitPoint.Empty) 
						return eDrawObjectMouseDown.Done; 
					m_l1Original.Line.ExtendLineToPoint(apprarentISPoint); 
					m_l2Original.Line.ExtendLineToPoint(apprarentISPoint); 
					m_l1NewPoint.SetLine(m_l1Original.Line); 
					m_l2NewPoint.SetLine(m_l2Original.Line); 
					canvas.DataModel.AfterEditObjects(this); 
					return eDrawObjectMouseDown.Done; 
				} 
 
				m_l1NewPoint.SetNewPoints(m_l1Original.Line, m_l1Original.MousePoint, intersectpoint); 
				m_l2NewPoint.SetNewPoints(m_l2Original.Line, m_l2Original.MousePoint, intersectpoint); 
				canvas.DataModel.AfterEditObjects(this); 
				return eDrawObjectMouseDown.Done; 
			} 
			return eDrawObjectMouseDown.Done; 
		} 
		public void OnMouseUp(ICanvas canvas, UnitPoint point, ISnapPoint snappoint) 
		{ 
		} 
		public void OnKeyDown(ICanvas canvas, KeyEventArgs e) 
		{ 
		} 
		public void Finished() 
		{ 
			SetHint(""); 
			if (m_l1Original.Line != null) 
				m_l1Original.Line.Highlighted = false; 
			if (m_l2Original.Line != null) 
				m_l2Original.Line.Highlighted = false; 
		} 
		public void Undo() 
		{ 
			m_l1Original.ResetLine(); 
			m_l2Original.ResetLine(); 
		} 
		public void Redo() 
		{ 
			m_l1NewPoint.ResetLine(); 
			m_l2NewPoint.ResetLine(); 
		} 
	} 
}