C# Axes.Axis類代碼示例

        /// <summary>
        /// Renders the specified axis.
        /// </summary>
        /// <param name="axis">The axis.</param>
        /// <param name="pass">The pass.</param>
        public override void Render(Axis axis, int pass)
        {
            base.Render(axis, pass);

            double totalShift = axis.AxisDistance + axis.PositionTierMinShift;
            double tierSize = axis.PositionTierSize - this.Plot.AxisTierDistance;

            // store properties locally for performance
            double plotAreaLeft = this.Plot.PlotArea.Left;
            double plotAreaRight = this.Plot.PlotArea.Right;
            double plotAreaTop = this.Plot.PlotArea.Top;
            double plotAreaBottom = this.Plot.PlotArea.Bottom;

            // Axis position (x or y screen coordinate)
            double axisPosition = 0;
            double titlePosition = 0;

            switch (axis.Position)
            {
                case AxisPosition.Left:
                    axisPosition = plotAreaLeft - totalShift;
                    titlePosition = axisPosition - tierSize;
                    break;
                case AxisPosition.Right:
                    axisPosition = plotAreaRight + totalShift;
                    titlePosition = axisPosition + tierSize;
                    break;
                case AxisPosition.Top:
                    axisPosition = plotAreaTop - totalShift;
                    titlePosition = axisPosition - tierSize;
                    break;
                case AxisPosition.Bottom:
                    axisPosition = plotAreaBottom + totalShift;
                    titlePosition = axisPosition + tierSize;
                    break;
            }

            if (axis.PositionAtZeroCrossing)
            {
                var perpendicularAxis = axis.IsHorizontal() ? this.Plot.DefaultYAxis : this.Plot.DefaultXAxis;
                axisPosition = perpendicularAxis.Transform(0);
            }

            if (pass == 0)
            {
                this.RenderMinorItems(axis, axisPosition);
            }

            if (pass == 1)
            {
                this.RenderMajorItems(axis, axisPosition, titlePosition);
                this.RenderAxisTitle(axis, titlePosition);
            }
        }

        /// <summary>
        /// Inverse transform the specified screen point.
        /// </summary>
        /// <param name="x">The x coordinate.</param>
        /// <param name="y">The y coordinate.</param>
        /// <param name="yaxis">The y-axis.</param>
        /// <returns>The data point.</returns>
        public override DataPoint InverseTransform(double x, double y, Axis yaxis)
        {
            var angleAxis = yaxis as AngleAxis;
            if (angleAxis == null)
            {
                throw new InvalidOperationException("Polar angle axis not defined!");
            }

            x -= this.MidPoint.x;
            y -= this.MidPoint.y;
            y *= -1;
            double th = Math.Atan2(y, x);
            double r = Math.Sqrt((x * x) + (y * y));
            x = (r / this.Scale) + this.Offset;
            y = (th / angleAxis.Scale) + angleAxis.Offset;
            return new DataPoint(x, y);
        }

        /// <summary>
        /// Renders the specified axis.
        /// </summary>
        /// <param name="axis">The axis.</param>
        /// <param name="pass">The pass.</param>
        /// <exception cref="System.NullReferenceException">Angle axis should not be <c>null</c>.</exception>
        public override void Render(Axis axis, int pass)
        {
            base.Render(axis, pass);

            var angleAxis = this.Plot.DefaultAngleAxis;

            if (angleAxis == null)
            {
                throw new NullReferenceException("Angle axis should not be null.");
            }

            angleAxis.UpdateActualMaxMin();

            var majorTicks = MajorTickValues.Where(x => x > axis.ActualMinimum && x <= axis.ActualMaximum).ToArray();

            if (pass == 0 && this.MinorPen != null)
            {
                var minorTicks = MinorTickValues.Where(x => x >= axis.ActualMinimum && x <= axis.ActualMaximum && !majorTicks.Contains(x)).ToArray();

                foreach (var tickValue in minorTicks)
                {
                    this.RenderTick(axis, angleAxis, tickValue, this.MinorPen);
                }
            }

            if (pass == 0 && this.MajorPen != null)
            {
                foreach (var tickValue in majorTicks)
                {
                    this.RenderTick(axis, angleAxis, tickValue, this.MajorPen);
                }
            }

            if (pass == 1)
            {
                foreach (double tickValue in majorTicks)
                {
                    this.RenderTickText(axis, tickValue, angleAxis);
                }
            }
        }

 /// <summary>
 /// Resets the specified axis.
 /// </summary>
 /// <param name="axis">
 /// The axis.
 /// </param>
 public void Reset(Axis axis)
 {
     axis.Reset();
 }

 /// <summary>
 /// Zooms the specified axis to the specified values.
 /// </summary>
 /// <param name="axis">
 /// The axis.
 /// </param>
 /// <param name="p1">
 /// The new minimum value.
 /// </param>
 /// <param name="p2">
 /// The new maximum value.
 /// </param>
 public void Zoom(Axis axis, double p1, double p2)
 {
     axis.Zoom(p1, p2);
     this.RefreshPlot(false);
 }

 /// <summary>
 /// Checks if the specified value is valid.
 /// </summary>
 /// <param name="v">The value.</param>
 /// <param name="yaxis">The y axis.</param>
 /// <returns>True if the value is valid.</returns>
 public virtual bool IsValidPoint(double v, Axis yaxis)
 {
     return !double.IsNaN(v) && !double.IsInfinity(v);
 }

 /// <summary>
 /// Determines whether the point is valid.
 /// </summary>
 /// <param name="pt">The point.</param>
 /// <param name="xaxis">The x axis.</param>
 /// <param name="yaxis">The y axis.</param>
 /// <returns><c>true</c> if [is valid point] [the specified pt]; otherwise, <c>false</c>.</returns>
 public virtual bool IsValidItem(HighLowItem pt, Axis xaxis, Axis yaxis)
 {
     return !double.IsNaN(pt.X) && !double.IsInfinity(pt.X) && !double.IsNaN(pt.High)
            && !double.IsInfinity(pt.High) && !double.IsNaN(pt.Low) && !double.IsInfinity(pt.Low);
 }

        /// <summary>
        /// Renders the minor items.
        /// </summary>
        /// <param name="axis">The axis.</param>
        /// <param name="axisPosition">The axis position.</param>
        protected virtual void RenderMinorItems(Axis axis, double axisPosition)
        {
            double eps = axis.ActualMinorStep * 1e-3;
            double actualMinimum = axis.ActualMinimum;
            double actualMaximum = axis.ActualMaximum;

            double plotAreaLeft = this.Plot.PlotArea.Left;
            double plotAreaRight = this.Plot.PlotArea.Right;
            double plotAreaTop = this.Plot.PlotArea.Top;
            double plotAreaBottom = this.Plot.PlotArea.Bottom;
            bool isHorizontal = axis.IsHorizontal();

            double a0;
            double a1;
            var minorSegments = new List<ScreenPoint>();
            var minorTickSegments = new List<ScreenPoint>();

            this.GetTickPositions(axis, axis.TickStyle, axis.MinorTickSize, axis.Position, out a0, out a1);

            foreach (double value in this.MinorTickValues)
            {
                if (value < actualMinimum - eps || value > actualMaximum + eps)
                {
                    continue;
                }

                if (this.MajorTickValues.Contains(value))
                {
                    continue;
                }

                if (axis.PositionAtZeroCrossing && Math.Abs(value) < eps)
                {
                    continue;
                }

                double transformedValue = axis.Transform(value);

                if (isHorizontal)
                {
                    SnapTo(plotAreaLeft, ref transformedValue);
                    SnapTo(plotAreaRight, ref transformedValue);
                }
                else
                {
                    SnapTo(plotAreaTop, ref transformedValue);
                    SnapTo(plotAreaBottom, ref transformedValue);
                }

                // Draw the minor grid line
                if (this.MinorPen != null)
                {
                    if (isHorizontal)
                    {
                        minorSegments.Add(new ScreenPoint(transformedValue, plotAreaTop));
                        minorSegments.Add(new ScreenPoint(transformedValue, plotAreaBottom));
                    }
                    else
                    {
                        if (transformedValue < plotAreaTop || transformedValue > plotAreaBottom)
                        {
                        }

                        minorSegments.Add(new ScreenPoint(plotAreaLeft, transformedValue));
                        minorSegments.Add(new ScreenPoint(plotAreaRight, transformedValue));
                    }
                }

                // Draw the minor tick
                if (axis.TickStyle != TickStyle.None && axis.MinorTickSize > 0)
                {
                    if (isHorizontal)
                    {
                        minorTickSegments.Add(new ScreenPoint(transformedValue, axisPosition + a0));
                        minorTickSegments.Add(new ScreenPoint(transformedValue, axisPosition + a1));
                    }
                    else
                    {
                        minorTickSegments.Add(new ScreenPoint(axisPosition + a0, transformedValue));
                        minorTickSegments.Add(new ScreenPoint(axisPosition + a1, transformedValue));
                    }
                }
            }

            // Draw all the line segments);
            if (this.MinorPen != null)
            {
                this.RenderContext.DrawLineSegments(minorSegments, this.MinorPen);
            }

            if (this.MinorTickPen != null)
            {
                this.RenderContext.DrawLineSegments(minorTickSegments, this.MinorTickPen);
            }
        }

 /// <summary>
 /// Check if the data series is using the specified axis.
 /// </summary>
 /// <param name="axis">An axis.</param>
 /// <returns>True if the axis is in use.</returns>
 protected internal override bool IsUsing(Axis axis)
 {
     return false;
 }

        /// <summary>
        /// Gets the axis title position, rotation and alignment.
        /// </summary>
        /// <param name="axis">The axis.</param>
        /// <param name="titlePosition">The title position.</param>
        /// <param name="angle">The angle.</param>
        /// <param name="halign">The horizontal alignment.</param>
        /// <param name="valign">The vertical alignment.</param>
        /// <returns>The <see cref="ScreenPoint" />.</returns>
        protected virtual ScreenPoint GetAxisTitlePositionAndAlignment(
            Axis axis,
            double titlePosition,
            ref double angle,
            ref HorizontalAlignment halign,
            ref VerticalAlignment valign)
        {
            double middle = axis.IsHorizontal()
                                ? Lerp(axis.ScreenMin.X, axis.ScreenMax.X, axis.TitlePosition)
                                : Lerp(axis.ScreenMax.Y, axis.ScreenMin.Y, axis.TitlePosition);

            if (axis.PositionAtZeroCrossing)
            {
                middle = Lerp(axis.Transform(axis.ActualMaximum), axis.Transform(axis.ActualMinimum), axis.TitlePosition);
            }

            switch (axis.Position)
            {
                case AxisPosition.Left:
                    return new ScreenPoint(titlePosition, middle);
                case AxisPosition.Right:
                    valign = VerticalAlignment.Bottom;
                    return new ScreenPoint(titlePosition, middle);
                case AxisPosition.Top:
                    halign = HorizontalAlignment.Center;
                    valign = VerticalAlignment.Top;
                    angle = 0;
                    return new ScreenPoint(middle, titlePosition);
                case AxisPosition.Bottom:
                    halign = HorizontalAlignment.Center;
                    valign = VerticalAlignment.Bottom;
                    angle = 0;
                    return new ScreenPoint(middle, titlePosition);
                default:
                    throw new ArgumentOutOfRangeException("axis");
            }
        }

        /// <summary>
        /// Renders the major items.
        /// </summary>
        /// <param name="axis">The axis.</param>
        /// <param name="axisPosition">The axis position.</param>
        /// <param name="titlePosition">The title position.</param>
        /// <param name="drawAxisLine">Draw the axis line if set to <c>true</c>.</param>
        protected virtual void RenderMajorItems(Axis axis, double axisPosition, double titlePosition, bool drawAxisLine)
        {
            double eps = axis.ActualMinorStep * 1e-3;

            double actualMinimum = axis.ActualMinimum;
            double actualMaximum = axis.ActualMaximum;

            double plotAreaLeft = this.Plot.PlotArea.Left;
            double plotAreaRight = this.Plot.PlotArea.Right;
            double plotAreaTop = this.Plot.PlotArea.Top;
            double plotAreaBottom = this.Plot.PlotArea.Bottom;
            bool isHorizontal = axis.IsHorizontal();

            double a0;
            double a1;
            var majorSegments = new List<ScreenPoint>();
            var majorTickSegments = new List<ScreenPoint>();
            this.GetTickPositions(axis, axis.TickStyle, axis.MajorTickSize, axis.Position, out a0, out a1);

            foreach (double value in this.MajorTickValues)
            {
                if (value < actualMinimum - eps || value > actualMaximum + eps)
                {
                    continue;
                }

                if (axis.PositionAtZeroCrossing && Math.Abs(value) < eps)
                {
                    continue;
                }

                double transformedValue = axis.Transform(value);
                if (isHorizontal)
                {
                    SnapTo(plotAreaLeft, ref transformedValue);
                    SnapTo(plotAreaRight, ref transformedValue);
                }
                else
                {
                    SnapTo(plotAreaTop, ref transformedValue);
                    SnapTo(plotAreaBottom, ref transformedValue);
                }

                if (this.MajorPen != null)
                {
                    if (isHorizontal)
                    {
                        majorSegments.Add(new ScreenPoint(transformedValue, plotAreaTop));
                        majorSegments.Add(new ScreenPoint(transformedValue, plotAreaBottom));
                    }
                    else
                    {
                        majorSegments.Add(new ScreenPoint(plotAreaLeft, transformedValue));
                        majorSegments.Add(new ScreenPoint(plotAreaRight, transformedValue));
                    }
                }

                if (axis.TickStyle != TickStyle.None && axis.MajorTickSize > 0)
                {
                    if (isHorizontal)
                    {
                        majorTickSegments.Add(new ScreenPoint(transformedValue, axisPosition + a0));
                        majorTickSegments.Add(new ScreenPoint(transformedValue, axisPosition + a1));
                    }
                    else
                    {
                        majorTickSegments.Add(new ScreenPoint(axisPosition + a0, transformedValue));
                        majorTickSegments.Add(new ScreenPoint(axisPosition + a1, transformedValue));
                    }
                }
            }

            // Render the axis labels (numbers or category names)
            foreach (double value in this.MajorLabelValues)
            {
                if (value < actualMinimum - eps || value > actualMaximum + eps)
                {
                    continue;
                }

                if (axis.PositionAtZeroCrossing && Math.Abs(value) < eps)
                {
                    continue;
                }

                double transformedValue = axis.Transform(value);
                if (isHorizontal)
                {
                    SnapTo(plotAreaLeft, ref transformedValue);
                    SnapTo(plotAreaRight, ref transformedValue);
                }
                else
                {
//.........這裏部分代碼省略.........

        /// <summary>
        /// Renders major tick text
        /// </summary>
        /// <param name="axis">The axis.</param>
        /// <param name="x">The x-value.</param>
        /// <param name="angleAxis">The angle axis.</param>
        private void RenderTickText(Axis axis, double x, Axis angleAxis)
        {
            var actualAngle = GetActualAngle(axis, angleAxis);
            var dx = axis.AxisTickToLabelDistance * Math.Sin(actualAngle);
            var dy = -axis.AxisTickToLabelDistance * Math.Cos(actualAngle);

            HorizontalAlignment ha;
            VerticalAlignment va;
            GetTickTextAligment(actualAngle, out ha, out va);

            var pt = axis.Transform(x, angleAxis.Angle, angleAxis);
            pt = new ScreenPoint(pt.X + dx, pt.Y + dy);

            string text = axis.FormatValue(x);
            this.RenderContext.DrawMathText(
                pt,
                text,
                axis.ActualTextColor,
                axis.ActualFont,
                axis.ActualFontSize,
                axis.ActualFontWeight,
                axis.Angle,
                ha,
                va);
        }

        /// <summary>
        /// Zooms at the specified position.
        /// </summary>
        /// <param name="axis">
        /// The axis.
        /// </param>
        /// <param name="factor">
        /// The zoom factor.
        /// </param>
        /// <param name="x">
        /// The position to zoom at.
        /// </param>
        public void ZoomAt(Axis axis, double factor, double x = double.NaN)
        {
            if (double.IsNaN(x))
            {
                double sx = (axis.Transform(axis.ActualMaximum) + axis.Transform(axis.ActualMinimum)) * 0.5;
                x = axis.InverseTransform(sx);
            }

            axis.ZoomAt(factor, x);
        }

        /// <summary>
        /// Renders a tick by drawing an lot of segments
        /// </summary>
        /// <param name="axis">The axis.</param>
        /// <param name="angleAxis">The angle axis.</param>
        /// <param name="x">The x-value.</param>
        /// <param name="pen">The pen.</param>
        private void RenderTickArc(Axis axis, AngleAxis angleAxis, double x, OxyPen pen)
        {
            // caution: make sure angleAxis.UpdateActualMaxMin(); has been called
            var minAngle = angleAxis.ActualMinimum;
            var maxAngle = angleAxis.ActualMaximum;

            // number of segment to draw a full circle
            // - decrease if you want get more speed
            // - increase if you want more detail
            // (making a public property of it would be a great idea)
            const double MaxSegments = 90.0;

            // compute the actual number of segments
            var segmentCount = (int)(MaxSegments * Math.Abs(angleAxis.EndAngle - angleAxis.StartAngle) / 360.0);

            var angleStep = (maxAngle - minAngle) / (segmentCount - 1);

            var points = new List<ScreenPoint>();

            for (var i = 0; i < segmentCount; i++)
            {
                var angle = minAngle + (i * angleStep);
                points.Add(axis.Transform(x, angle, angleAxis));
            }

            this.RenderContext.DrawLine(points, pen.Color, pen.Thickness, pen.ActualDashArray);
        }

        /// <summary>
        /// Renders a tick by drawing an ellipse
        /// </summary>
        /// <param name="axis">The axis.</param>
        /// <param name="angleAxis">The angle axis.</param>
        /// <param name="x">The x-value.</param>
        /// <param name="pen">The pen.</param>
        private void RenderTickCircle(Axis axis, Axis angleAxis, double x, OxyPen pen)
        {
            var zero = angleAxis.Offset;
            var center = axis.Transform(axis.ActualMinimum, zero, angleAxis);
            var right = axis.Transform(x, zero, angleAxis).X;
            var radius = right - center.X;
            var width = radius * 2;
            var left = right - width;
            var top = center.Y - radius;
            var height = width;

            this.RenderContext.DrawEllipse(new OxyRect(left, top, width, height), OxyColors.Undefined, pen.Color, pen.Thickness);
        }