Disappearing Pitchfork Lines

[Richard Von]

When the origin points of an Andrew's Pitchfork go off the screen to the left, the pitchfork lines disappear even if the trading range is within the lines. The lines should show as long as they are within the vertical range shown.

[NinjaTrader_Ray]

This limitation has been resolved for NT 6.5.

[saltminer]

Guys, this still happens with 6.5.1.8
I have a strategy drawing lines, but they flick on and off as I scroll back and forth. Why? That's not supposed to happen. I can scroll even just one bar, and a whole screen full of lines disappear.
It is always a juggle to adjust zoom and placement to be able to see the lines.

I know this is not how you intend it to work.

For the record, I just re-installed, throwing out the folder in the Documents folder for good measure.
No improvement.

saltminer

Hey, i just noticed it deletes ALL graphic items on the strategy. Even dots and arrows. Scrolling one bar back and forward turns them on and off in the display. The strategy does nothing like that intentionally. It draws stuff and moves on, with a unique String identifier. This is baffling.

Maybe this is relevant...
My lines sometimes have end points that are way off the chart vertically, e.g. a trendline 100 bars later might be 5 or 10% above where price is.
I have the "autoscale" flag set to false in the DrawLine(...)
Is there any kind of fancy graphic optimising guesswork that charts do that might be tripping up?

[NinjaTrader_RJ]

Guys, this still happens with 6.5.1.8
I have a strategy drawing lines, but they flick on and off as I scroll back and forth. Why? That's not supposed to happen. I can scroll even just one bar, and a whole screen full of lines disappear.
It is always a juggle to adjust zoom and placement to be able to see the lines.

I know this is not how you intend it to work.

For the record, I just re-installed, throwing out the folder in the Documents folder for good measure.
No improvement.

saltminer

Hey, i just noticed it deletes ALL graphic items on the strategy. Even dots and arrows. Scrolling one bar back and forward turns them on and off in the display. The strategy does nothing like that intentionally. It draws stuff and moves on, with a unique String identifier. This is baffling.

Hello Saltminer,

Thank you for your post.

Unfortunately I am not able to reproduce. The Andrew's Pitchfork stays viewable on the chart as I scroll left and right.

Try updating your video drivers as those can sometimes cause flickering.

[saltminer]

It was really driving me crazy so I tried a whole bunch of things, and I fixed it by constraining the Line's end-point distance from the visible price level.

In other words, if the end of my line was more than 2% away from price, I didn't draw it. I also disabled vertical lines (which may have created infinity values).
HEY PRESTO, everything works.

I believe the data was valid before, just far away.

Maybe something about the chart drawing logic you have to optimise performance?

saltminer

[saltminer]

Ah, I think it was my fault.. trying to draw lines with inifinity slope. It seems to crash the chart-drawing logic, without generating an error in the log. Once you scroll past the offending line, the chart gets itself together again.
saltminer