The Fuction GetXByTime() returns weird values

[Stanfillirenfro]

Hello!

I am trying to have the xCoordinate in OnRender().
I have the following code:

protected override void OnRender(ChartControl chartControl, ChartScale chartScale)
{
    base.OnRender(chartControl, chartScale);
    DateTime timeToCheck = new DateTime(2023, 5, 24, 11, 0, 0);
    int xCoordinate = chartControl.GetXByTime(timeToCheck);
    Print(xCoordinate);
}​

This code is returning negative high numbers in absolute values, what is surprising for me. I have -14055.

I have also tried with

DateTime timeToCheck = new DateTime(Time[0]);

and also here, I have the same behaviour.

How can I have the x coordinate in OnRender() using the function GetXByTime()? What is wrong in my code?

I would appreciate any help.

Best regards

[QuantKey_Bruce]

The negative numbers mean that the pixel coordinate is off your screen because the chart doesn't go back that far. Or, with multiple monitors, the pixel coordinates could be visible on another monitor left of the primary one, could they not?

It should be stated that absolute pixel coordinate (0,0) is the upper left of your PRIMARY monitor. If you have a monitor positioned in Windows to the left of that, every single pixel on that one will have an ultimate x coordinate that is negative.

That having been said, the coordinates should not be negative relative to the client window of the chart component unless the first thing is true - that datetime is off the chart's visible scrolled/zoomed area.

Also, I would be very cautious about using something like "Time[0]" in OnRender - basically, don't do that. You should be using ChartBars or ChartBars.Bars and .GetTime(index) etc. because you don't have the right context there to be using Time. If you have more than one data series, you can't even be sure which one that would refer to, or whether CurrentBar is >= 0.

If you're just doing a quick test, you might try DateTime.Now.

[Stanfillirenfro]

Many thanks QuantKey_Bruce for your valuable help.

This problem is fixed. Many thanks again!

I would be gratefull to you if you could tell me if ChartControl and ChartScale can be used outside of OnRender(). Is it possible to get the x Coordinate for example with ChartControl outside of OnRender()? What would be the function to be added or removed to achieve the goal?

Many thanks in advance

[QuantKey_Bruce]

Well, ChartControl is accessible outside of OnRender, but you would have to always check for nulls. Also, bear in mind your indicator or strategy may not be directly on a chart e.g. your indicator could be nested in a strategy or on market analyzer, or your strategy could be in strategy analyzer, and in these cases ChartControl will be null so you have to always have a valid code path when it is null. I don't think it's wise to be doing any actual drawing outside of OnRender - that defeats the whole purpose. In particular, you defintiely do not want to do any actual drawing on each tick or faster than every 250 ms or you will greatly decrease the platform's performance and stability. Sometimes you need access to ChartControl to do something like grab the color of the axis brush so you can coordinate some other drawing with that same color, but I would really encourage you to stick with NinjaTrader's modular design and do your custom rendering in OnRender and your calculations in OnBarUpdate (or OnMarketData if appropriate). One has to ask why one needs an x coordinate outside of OnRender, and the answer is probably going to lead to being told you shouldn't do it that way - you should do your drawing in OnRender. Most of the time when someone is trying to force it to render faster or to custom draw outside of OnRender it turns out they're doing something regrettable that really shouldn't be done that way and that will lead to instability or crashes in other environments e.g. they're testing and think it's okay on their desktop, but when run on a VPS or on an old laptop it crashes the platform or makes it run so slowly no one would be able to stand it. It's designed the way it is for a reason, and it's generally well thought out so it's good to try to work with the design, and the design says you do your custom drawing in OnRender.

[Stanfillirenfro]

Many thanks QuantKey_Bruce for yor explanation.

I have gone one step further with my above code and another problem has arose.
I have used the following loop to find the x Coordinate and everything was FINE:

for(int barIndex = ChartBars.FromIndex; barIndex <= ChartBars.ToIndex; barIndex++)
{
    DateTime timeValue = Bars.GetTime(barIndex);
    int xCoordinate = chartControl.GetXByTime(timeValue);​
}

But when I used a loop with predefined number such as 50 for example, I continue to have negative values.

for(int barIndex = 0; barIndex <= 50; barIndex++)
{
    DateTime timeValue = Bars.GetTime(barIndex);
    int xCoordinate = chartControl.GetXByTime(timeValue);​
}​

I make it sure that the bars are also visible on the display.
What could be the problem please and how to fix it?

Many thanks

[QuantKey_Bruce]

I don't understand in this case why you're not getting the X by the index itself: https://ninjatrader.com/support/help...bybarindex.htm.

Also, you need to be checking that 0 and 50 are within the range ChartBars.FromIndex and ChartBars.ToIndex.

Perhaps, if you have to, you could do something like:

for (int barIndex = Math.Max(0, ChartBars.FromIndex); barIndex <= Math.Min(50, ChartBars.ToIndex); barIndex++)
{
int xCoordinate = chartControl.GetXByBarIndex(ChartBars, barIndex);
}

In this way you can be sure that the 0..50 is indeed on the display. Most likely, it isn't, if as you say, it fails. In all likelihood, bar 0 is off the screen to the left, which perfectly explains why X would be negative.