Plotting background colors between bands

[rt-trader]

I want toaddcode to a Ninja Script so that a different background color can be drawn between say an Upper and Lower Bollinger band. Apparently this can be done by over riding the Plot method with a custom drawing using native .Net graphics classes.

If anyone knows how to do this and is happy to share could you please post a few lines of sample code which shows the underlying instruction syntax necessary to achieve the desired result.

Many thanks

[tquinn]

imported post

I'm a beginner with C#, and I wanted the same thing. I could not figure how to do it with .Net graphics so I settled for using NinjaScript to draw rectangles.

if (Middle[0]>Middle[1])
BandColor=Color.Blue;
else
BandColor=Color.Red;
DrawRectangle("R"+CurrentBar.ToString(),
1,Math.Max(Lower[0],Lower[1]),
0,Math.Min(Upper[0],Upper[1]),
Color.Transparent,BandColor,1);

[rt-trader]

imported post

Thankyou for the post tquinn - will give what you suggest a try......

[Raditz]

imported post

Hi

Try this

SolidBrush brush = new SolidBrush(Color.Gray);
int barWidth = ChartControl.ChartStyle.GetBarPaintWidth(ChartControl.BarWidth);
SmoothingMode oldSmoothingMode = graphics.SmoothingMode;
GraphicsPath path = new GraphicsPath();

for (int seriesIndex = 0; seriesIndex < 2; seriesIndex++)
{
 int lastX = -1;
 int lastY = -1;
 DataSeries series = (DataSeries) Values[seriesIndex];
 double val = 0;
 Gui.Chart.Plot plot = Plots[seriesIndex];

 for (int barIndex = 0; barIndex < ChartControl.BarsPainted; barIndex++)
 {
  int idx = ChartControl.LastBarPainted - ChartControl.BarsPainted + 1 + barIndex;
  if (idx < 0 || idx >= Input.Count || (!ChartControl.ShowBarsRequired && idx < BarsRequired))
   continue;

  val = series.Get(idx);

  int   x = (int) (ChartControl.CanvasRight - ChartControl.BarMarginRight - barWidth / 2
   - (ChartControl.BarsPainted - 1) * ChartControl.BarSpace + barIndex * ChartControl.BarSpace) + 1;
  int   y = (int) ((bounds.Y + bounds.Height) - ((val - min ) / (max - min)) * bounds.Height);

  if (lastX >= 0) 
  {
   path.AddLine(lastX - plot.Pen.Width / 2, lastY, x - plot.Pen.Width / 2, y);
  }

  lastX = x;
  lastY = y;
 }
 path.Reverse();
 
}
graphics.SmoothingMode = SmoothingMode.AntiAlias;
graphics.FillPath(brush, path);
graphics.SmoothingMode = oldSmoothingMode;

Muly
Final
http://fin-alg.com/

[tquinn]

imported post

Muly,
I'm not good enough with C# to use this. I placed it in OnBarUpdate() and it produced a bunch of compile errors. I'm sure it is my lack of C# skills.

[rt-trader]

imported post

Wow,

Well beyond my skills too! Thanks heaps for posting this Muly.Iattempt to get it working...

Cheers

[Raditz]

imported post

Hi

the post bellow is the code for the Plot function

public override void Plot(Graphics graphics, Rectangle bounds, double min, double max)

Muly
Final
http://fin-alg.com/

[tquinn]

imported post

Muly,
It is good to get a lesson on how much there is to learn about a new programmimg language. If I understand your code, it is plotting vertical lines between Values[0]
and Values[1]. So I've created only those 2 Values.

This is what I have so far, but it still will not compile. Errors about "using directives" and "assemble references", things I know nothing about.

protected override void Initialize()
{
Add(new Plot(Color.Orange, "Upper band"));
Add(new Plot(Color.Orange, "Lower band"));
}

protected override void OnBarUpdate()
{
Upper.Set(SMA(14)[0] + 2 * StdDev(14)[0]);
Lower.Set(SMA(14)[0] - 2 * StdDev(14)[0]);
}

public override void Plot(Graphics graphics, Rectangle bounds, double min, double max)
{

// Your code from below
}

[NinjaTrader_Dierk]

imported post

Please paste in error messages. They likely are not related to Muly's code. Likely your NT installation is screwed up.

[Raditz]

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Probebly the using directive is missing some here is my

using System;
using System.Diagnostics;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.ComponentModel;
using System.Xml.Serialization;
using NinjaTrader.Data;
using NinjaTrader.Gui.Chart;

make sure you include all

Muly
Final
http://fin-alg.com/

[tquinn]

imported post

Thanks all,
I was missing " using System.Drawing.Drawing2D;", Muly's code runs fine now.

Now I need to learn how to put the Colored area behind the price bars, and maybe change the opacity. I'll save this lesson for a later day.

I need to get back to Mastering NinjaScript before I wander too far off track, into the world of C# and .NET.

Thanks again

[NinjaTrader_Dierk]

imported post

Tom,

Just curious:

"using System.Drawing.Drawing2D;"

should be part of the code generated by the indicator wizard. Do you know why it was not there?

Thanks