Web-Remotepanels and different Windows DPI setting

[Jeffrey Habets]

Ok, I thought I knew all the tricks to make LV frontpanels behave nicely in all screen resolutions and DPI-settings but here's one thing I can't solve and I'm not sure this is a LabVIEW (runtime) bug or something Windows/ActiveX-isch thing.

I have a LV app running on a cRIO target. The UI is exposed to the user using a webpage with an embedded panel. This runs perfectly on every resolution with the standard dpi-setting of 96dpi. Problems begin to occur when the user has selected 120dpi which is ofcourse the case with our customer. Actually I see this happen often with the crappy non-standard resolutions nowadays.

Actually LabVIEW does pretty well with the 120dpi setting when you do not use the application font, but rather something like Arial. If you want to use application font you need to prepare your entire UI for the larger DPI setting unless you think overlapping buttons and such are nice.

With the remotepanels something odd seems to happen. See the pics below.

The left pic shows the webpage (which is designed of a minimum vertical resolution of 1024 pixels) on my desktop PC with a resolution of 1280x1024@96dpi, it's how it should be. On this same system @120dpi, it also displays as you'd expect and the picture is the same.

The right pic shows the webpage on a widescreen laptop with screen resolution of 1680x1050@120dpi. Here it seems the FP itselfs 'shrunk' (since I'd expect it to be about the height of the screenres) and at the same time the embedded LabVIEWControl object grew, since it now expands beyond the vertical screen size (the actual object height=888 pixels).

Also if I switch resolution on the laptop to 1280x1024@120dpi, the webpage displays the same as at 1680x1050@120 whereas it displays correct in this very same resolution on my desktop system.

So my very fuzzy conclusion would be that on some systems with an unusual native screenresolution at a 120dpi setting some unexpected behaviour occurs when using remotepanels in a webpage. The question remains wether this is a LV runtime problem or Windows/ActiveX related.

Has anyone encountered something similar?

Or better yet, tell me it's not a bug/problem and the solution is actually very simple.