C# Cairo.LineTo方法代码示例

        /// <summary>
        /// Draw the robot taking into account the center x and y position of the map which
        /// will be different from the true center x and y positions on the drawing context.
        /// This method will result in a red wheeled robot with black tyres being drawn at
        /// the robots location on the map.
        /// 
        /// The scale value is currently unused but it could be useful if the map was scaled
        /// in some way for example a mini-map may be 10 times smaller than the original 
        /// results in 1:10 scale robot.
        /// </summary>
        /// <param name="cairoContext">Cairo context to draw to (assuming a map).</param>
        /// <param name="centerX">Center x position of map to draw onto.</param>
        /// <param name="centerY">Center y position of map to draw onto.</param>
        /// <param name="scale">Scale currently unused.</param>
        public void Draw(Cairo.Context cairoContext, int centerX, int centerY, double scale)
        {
            // Scale up to centimeters.
            int width = (int)(robot.Width * 100);
            int height = (int)(robot.Height * 100);
            int x = (int)(robot.X * 100);
            int y = (int)(robot.Y * 100);

            // Set a red colour.
            cairoContext.SetSourceRGB(255, 0, 0);

            cairoContext.LineWidth = 1.0;
            cairoContext.LineCap = LineCap.Butt;

            cairoContext.Translate (centerX + x, centerY - y);
            cairoContext.Rotate (relativeRotation); // Rotate the robot based on its orientation in radians.

            // Draw the robot as a triangle.
            cairoContext.MoveTo (0, -height / 2);
            cairoContext.LineTo (-width / 2, height / 2);
            cairoContext.LineTo (width / 2, height / 2);
            cairoContext.LineTo (0, -height / 2);
            cairoContext.Stroke ();

            // Reset the drawing context.
            cairoContext.Rotate (-relativeRotation);
            cairoContext.Translate (-(centerX + x), -(centerY - y));
        }

        protected void DrawHorizontalSectionIndicator(string text, Cairo.Context cr, Pango.Layout layout, double x, double y, double w, out double h)
        {
            cr.MoveTo(x,y);
            cr.LineTo(x,y+SectionSerifeWidth*2);
            cr.MoveTo(x,y+SectionSerifeWidth);
            cr.LineTo(x+w,y+SectionSerifeWidth);
            cr.MoveTo(x+w,y);
            cr.LineTo(x+w,y+SectionSerifeWidth*2);
            cr.Color = new Cairo.Color(0, 0, 0);
            cr.LineWidth = 1;
            cr.Stroke();

            layout.Width = (int)(w*Pango.Scale.PangoScale);
            layout.Alignment = Pango.Alignment.Center;
            layout.SetText (text);
            layout.Ellipsize = EllipsizeMode.Middle;
            layout.Justify = true;
            cr.Color = new Cairo.Color(0, 0, 0);
            cr.MoveTo(x,y+SectionSerifeWidth*2);
            Pango.CairoHelper.ShowLayout (cr, layout);

            int lw,lh;
            layout.GetPixelSize(out lw, out lh);
            h=(double)lh+SectionSerifeWidth*2;
        }

        public static void DrawRoundedRectangle(Cairo.Context gr, double x, double y,
		                                        double width, double height, double radius,
		                                        Cairo.Color color, Cairo.Color borderColor)
        {
            gr.Save();

            if((radius > height / 2) || (radius > width / 2))
                radius = Math.Min(height / 2, width / 2);

            gr.MoveTo(x, y + radius);
            gr.Arc(x + radius, y + radius, radius, Math.PI, -Math.PI / 2);
            gr.LineTo(x + width - radius, y);
            gr.Arc(x + width - radius, y + radius, radius, -Math.PI / 2, 0);
            gr.LineTo(x + width, y + height - radius);
            gr.Arc(x + width - radius, y + height - radius, radius, 0, Math.PI / 2);
            gr.LineTo(x + radius, y + height);
            gr.Arc(x + radius, y + height - radius, radius, Math.PI / 2, Math.PI);
            gr.ClosePath();
            gr.Restore();

            gr.LineJoin = LineJoin.Round;
            gr.Color = borderColor;
            gr.StrokePreserve();
            gr.Color = color;
            gr.Fill();
        }

        public static void RoundedRectangle(Cairo.Context c, RectangleD rect, double radius)
        {
            if (radius > (rect.Width /2) || radius > (rect.Height / 2)) {
                radius = Math.Min ((rect.Width /2), (rect.Height / 2));
            }

            c.Save ();

            /* Bottom Left */
            c.MoveTo(rect.X, rect.Y + radius);
            c.Arc (rect.X + radius, rect.Y + radius, radius, Math.PI, -Math.PI/2);
            c.LineTo (rect.X2 - radius, rect.Y);

            /* Bottom Right */
            c.Arc (rect.X2 - radius, rect.Y + radius, radius, -Math.PI/2, 0);
            c.LineTo (rect.X2, rect.Y2 - radius);

            /* Top Right */
            c.Arc (rect.X2 - radius, rect.Y2 - radius, radius, 0, Math.PI/2);
            c.LineTo (rect.X + radius, rect.Y2);

            /* Top Left */
            c.Arc(rect.X + radius, rect.Y2 - radius, radius, Math.PI/2, Math.PI);
            c.ClosePath ();

            c.Restore ();
        }

	static void draw (Cairo.Context gr, int width, int height)
	{
		double x=0.1,  y=0.5;
		double x1=0.4, y1=0.9, x2=0.6, y2=0.1, x3=0.9, y3=0.5;
		
				
		gr.Scale (width, height);
		gr.LineWidth = 0.04;		
		
		gr.MoveTo ( new PointD (x, y) );
		
		gr.CurveTo ( new PointD (x1, y1),
			     new PointD (x2, y2), 
			     new PointD (x3, y3)
			     );
		
		gr.Stroke ();
		
		gr.Color = new Color (1, 0.2, 0.2, 0.6);
		gr.LineWidth = 0.03;
		gr.MoveTo ( new PointD (x, y) );
		gr.LineTo ( new PointD (x1, y1) );
		gr.MoveTo ( new PointD (x2, y2) );
		gr.LineTo ( new PointD (x3, y3) );
		gr.Stroke ();						
	}

	static void draw (Cairo.Context gr, int width, int height)
	{
		int w, h;
		ImageSurface image;
		
		gr.Scale (width, height);
		gr.LineWidth = 0.04;
		
		gr.Arc (0.5, 0.5, 0.3, 0, 2*M_PI);
		gr.Clip ();
		gr.NewPath ();
		
		image = new ImageSurface("data/e.png");
		w = image.Width;
		h = image.Height;
		
		gr.Scale (1.0/w, 1.0/h);
		
		image.Show (gr, 0, 0);
		
		image.Destroy();
		
		gr.Arc (0.5, 0.5, 0.3, 0, 2 * M_PI);
		gr.Clip ();
		
		gr.NewPath ();
		gr.Rectangle (new PointD (0, 0), 1, 1);
		gr.Fill ();
		gr.Color = new Color (0, 1, 0, 1);
		gr.MoveTo ( new PointD (0, 0) );
		gr.LineTo ( new PointD (1, 1) );
		gr.MoveTo ( new PointD (1, 0) );
		gr.LineTo ( new PointD (0, 1) );
		gr.Stroke ();
	}

        static void draw (Cairo.Context gr, int width, int height)
	{
		double xc = 0.5;
		double yc = 0.5;
		double radius = 0.4;
		double angle1 = 45.0  * (M_PI/180.0);  /* angles are specified */
		double angle2 = 180.0 * (M_PI/180.0);  /* in radians           */
		
		gr.Scale (width, height);
		gr.LineWidth = 0.04;
		
		gr.ArcNegative (xc, yc, radius, angle1, angle2);
		gr.Stroke ();
		
		/* draw helping lines */
		gr.Color = new Color(1, 0.2, 0.2, 0.6);
		gr.Arc (xc, yc, 0.05, 0, 2*M_PI);
		gr.Fill ();
		gr.LineWidth = 0.03;
		gr.Arc (xc, yc, radius, angle1, angle1);
		gr.LineTo (new PointD(xc, yc));
		gr.Arc (xc, yc, radius, angle2, angle2);
		gr.LineTo (new PointD(xc, yc));
		gr.Stroke ();
	}

        public static void DrawTriangle(Cairo.Context g, double x, double y,
		                                int width, int height, Cairo.Color color)
        {
            g.Color = color;
            g.MoveTo(x, y);
            g.LineTo(x + width/2, y-height);
            g.LineTo(x - width/2, y-height);
            g.ClosePath();
            g.Fill();
            g.Stroke();
        }

		protected void DrawDiamond (Cairo.Context cr, double x, double y, double size)
		{
			x += 0.5; y += 0.5;
			size -= 2;
			cr.NewPath ();
			cr.MoveTo (x + size/2, y);
			cr.LineTo (x + size, y + size/2);
			cr.LineTo (x + size/2, y + size);
			cr.LineTo (x, y + size/2);
			cr.LineTo (x + size/2, y);
			cr.ClosePath ();
		}

        public static void RenderInvertedTriangle(Cairo.Context g, Cairo.Color c, double x, double y, int side)
        {
            g.Save();

            g.Color = c;
            g.MoveTo(x, y);
            g.LineTo(x - side / 2, y - side);
            g.LineTo(x + side / 2, y - side);
            g.LineTo(x, y);
            g.Fill();

            g.Restore();
        }

        public void draw(Cairo.Context cr)
        {
            cr.LineWidth = 3;
            cr.SetSourceRGB(0, 0.9, 0.0);

            //cr.Translate (l1.P1.X, l1.P1.Y);
            cr.MoveTo(position);

            cr.LineTo (position.X + width, position.Y);
            cr.LineTo (position.X + width, position.Y + height);
            cr.LineTo (position.X, position.Y + height);
            cr.LineTo (position.X, position.Y);

            cr.Stroke ();
        }

        public override void DrawFrameBorder(Cairo.Context cr, Gdk.Rectangle alloc)
        {
            if (IsPanelWidget) {
                return;
            } else if (!IsSourceViewWidget) {
                base.DrawFrameBorder (cr, alloc);
                return;
            }

            cr.SetSourceColor (TextMidColor);
            cr.LineWidth = 1.0;
            cr.Antialias = Cairo.Antialias.None;

            cr.MoveTo (alloc.Right - 1, alloc.Top);
            cr.LineTo (alloc.Right - 1, alloc.Bottom);
            cr.Stroke ();

            if (Widget.Allocation.Bottom < Widget.Toplevel.Allocation.Height) {
                cr.MoveTo (alloc.Left, alloc.Bottom - 1);
                cr.LineTo (alloc.Right, alloc.Bottom - 1);
                cr.Stroke ();
            }

            cr.Antialias = Cairo.Antialias.Default;
        }

        /// <summary>
        /// Draw the specified cairoContext, centerX, centerY and scale.
        /// </summary>
        /// <param name="cairoContext">Cairo context.</param>
        /// <param name="centerX">Center x.</param>
        /// <param name="centerY">Center y.</param>
        /// <param name="scale">Scale.</param>
        public void Draw(Cairo.Context cairoContext, int centerX, int centerY, double scale)
        {
            cairoContext.SetSourceRGB (0, 0, 200);
            cairoContext.LineWidth = 1.0;
            cairoContext.LineCap = LineCap.Butt;

            //cairoContext.MoveTo (OriginalX, -OriginalY);
            //int x = centerX;

            //Console.WriteLine ("point: " + (robot.PathPointList [robot.PathPointList.Count-1] [1]*100));

            //if (30 <= (robot.PathPointList [robot.PathPointList.Count - 1] [1] * 100))
            //{
            //robot.Halt ();
            //Console.WriteLine ("\n\n Has Gone 30cm \n\n");
            //}

            for (int i = 1; i < robot.PathPointList.Count; i++)
            {
                cairoContext.MoveTo (centerX + (robot.PathPointList [i - 1] [0] * 100), centerY - (robot.PathPointList [i - 1] [1] * 100));
                cairoContext.LineTo (centerX + (robot.PathPointList [i] [0] * 100), centerY - (robot.PathPointList [i] [1] * 100));
                //	Console.WriteLine (path[0]*100+" , "+ path[1]*100);
                cairoContext.Stroke ();
            }

            foreach (double[] path in robot.PathPointList)
            {
                //cairoContext.MoveTo (centerX - (path[0] * 100), centerY - (path[1] * 100));
            }
        }

		internal protected override void Draw (Cairo.Context cr, Cairo.Rectangle area, LineSegment lineSegment, int line, double x, double y, double lineHeight)
		{
			cr.MoveTo (x + 0.5, y);
			cr.LineTo (x + 0.5, y + lineHeight);
			cr.Color = color;
			cr.Stroke ();
		}

        private void Draw(Cairo.Context cr, int width, int heigth)
        {
            foreach (var path in pathPosition.Keys)
            {
                var pPosition = pathPosition[path];
                var begin = pPosition.Item1;
                var end = pPosition.Item2;

                cr.SetSourceRGB(1, 1, 1);
                cr.MoveTo(begin.X, begin.Y);
                cr.LineTo(end.X, end.Y);
                cr.Stroke();
                cr.SetSourceRGB(0, 0, 0);
            }

            foreach (var path in pathPosition.Keys)
            {
                var pPosition = pathPosition[path];
                var begin = pPosition.Item1;
                var end = pPosition.Item2;

                if (path is BlockingPath)
                {
                    var blockingPath = path as BlockingPath;

                    if (blockingPath.IsBlocked)
                    {
                        cr.SetSourceRGB(1, 0, 0);
                    }
                    else
                    {
                        cr.SetSourceRGB(0, 1, 0);
                    }

                    cr.Rectangle(new Cairo.Rectangle(end.X - 6, end.Y - 6, 12, 12));
                    cr.Fill();
                    cr.SetSourceRGB(0, 0, 0);
                }
                else if (path is SourcePath)
                {
                    var sourcePath = path as SourcePath;
                    cr.MoveTo(begin.X, begin.Y);
                    cr.TextPath(sourcePath.Queue.ToString());
                    cr.Fill();
                }

                foreach (var vehicle in path.VehiclePosition.Keys)
                {
                    var position = path.VehiclePosition[vehicle];
                    var r = position / path.Length;
                    var x = begin.X + (end.X - begin.X) * r;
                    var y = begin.Y + (end.Y - begin.Y) * r;

                    cr.Arc(x, y, 5, 0, 2 * Math.PI);
                    cr.Fill();
                }
            }

            cr.Stroke();
        }