in graphs you can use cursors and also change their properties to show lines…
Is there a way I could turn on the cursor lines on the IMAQ image when drawing the ROI?
I don't thing so.
You do have options, but it won't be easy.
If you want more power, you'll have to ditch all build in functionality, and go the DIY route. That means:
+ Show the image in an intensity graph, and use it's cursors and the picture overlay for drawing a selection box.
+ Or show the image in a picture control and do everything yourself. Both are hard, but once you get things going you do have all the power to customize as much as you want.
I'd go for the first option, as you get the cursor\coordinate handling for free. It's 'just' a matter of performing the right action (redraw selection) at the right events (cursor grab\move\release).
EDIT: Maybe the IMAQ image triggers events, and maybe you can draw the cursors manually based on those events. I'm not sure, and can't test it right now (no IMAQ installed). Worth a try.
load the JPG using the PictureFile functions.
Then use the PlotImage property…