How to do a polygon hit test?

[DancesWithBears]

I want to test to see if an enclosing candle body is contained within a polygon (in this case the polygon is a price channel).

When the price bar (which is also a polygon) leaves the enclosing polygon I need to set a condition.

How would I do this in Ninjatrader, would I use windows GDI?

[NinjaTrader_Austin]

Hi DancesWithBears, you'll need to run the math calculations to determine if something lies inside the polygon. I'm not sure how you're drawing the polygon, but if it done by selecting points, you can find the slope (y=mx+b) of the relevant lines and then run some logic to see if the price bar is inside (or outside) the polygon.

[DancesWithBears]

System.Windows.Shapes Namespace?

Do I have access to the System.Windows.Shapes Namespace? Then I can use Polygon class

[NinjaTrader_Austin]

I don't see any reason why you wouldn't have access to System.Windows.Shapes. If you do use .Shapes, unfortunately we can't provide support for any issues arising from its use.

Regardless, I took a look at the Polygon class in System.Windows.Shapes and you have to have points to create a polygon, so my previous point still stands about calculating the slope of the lines and running your own logic to determine position relative to that polygon.

PS. I like your name. I was once a counselor known as "Dances With Wolves" at a nature/science camp for 6th graders in the Yampa Valley.

[DancesWithBears]

Trying to avoid writing a hit test method

Austin,

Tried to add the
using System.Windows.Shapes;
but script doesn't compile. hmm?

Your point stands about how to create polygon vertices for the channel lines.

I am given y, and can derive m .
i.e. the polygon using y = mx + b.
then I move the line down via changing the b value to get my channel.

Now I have four points that enclose that surface.

I just want to create a polygon object because the class already supports hit testing (I don't want to test debug that logic if it exists.)
via :
Polygon.HitTestCore(GeometryHitTestParameters) Implements

OnBarUpdate() I just supply the high of the current bar.

If I can't use the Shapes namespace I might have to rethink.

I don't see any reason why you wouldn't have access to System.Windows.Shapes. If you do use .Shapes, unfortunately we can't provide support for any issues arising from its use.

Regardless, I took a look at the Polygon class in System.Windows.Shapes and you have to have points to create a polygon, so my previous point still stands about calculating the slope of the lines and running your own logic to determine position relative to that polygon.

PS. I like your name. I was once a counselor known as "Dances With Wolves" at a nature/science camp for 6th graders in the Yampa Valley.

[NinjaTrader_Austin]

Austin,

Tried to add the
using System.Windows.Shapes;
but script doesn't compile. hmm?

Copy + paste from the MSDN entry:

--------------------------------------------------
Shape Class

Provides a base class for shape elements, such as Ellipse, Polygon, and Rectangle.

Namespace: System.Windows.Shapes
Assembly: PresentationFramework (in PresentationFramework.dll)
--------------------------------------------------

Because of this, I think you'll need to add a reference to this PresentationFramework.dll for the "using System.Windows.Shapes;" statement to work. I'm not sure where this .dll file is located though. A general Google search might be of assistance.

In addition, I wasn't aware there was a function for a "hit test." That method seems like it would be easiest by far.