Illustrator processes faster when mouse cursor is moving over window

[matthewsjc1]

This is the strangest thing and I have no clue why it happens. I hadn't noticed until the other day that when my mouse cursor is moving over an open Illustrator document that is being processed by software I've written (accesses Illustrator via COM), Illustrator process the document WAY faster (it takes seconds instead of the usual couple minutes).

I decided to run a test and added a "counter" to the app that reads out how fast the paths in the document are being processed. Sure enough, when the cursor is not moving or not over the Illustrator window, the paths are processed at around 4 per second. When the cursor is moving over the Illustrator window, it jumps up to around 50  I checked Task Manager and the CPU percentage jumps up, as well, when the cursor is moving over the Illustrator window.

It's so strange I haven't been able to pinpoint the cause or find a way to reproduce it programatically, which would be very useful, as files would process far faster.

If anyone has experience, an explanation, or a way to reproduce this programmatically, I'd love to hear!

Thank you,

Jared Matthews

ESM Trading Company

[CarlosCanto]

that's a very unusual find, thanks for sharing! I'd do some testing and report back as soon as I have a chance.

thanks!

[CarlosCanto]

since I'm working on a script as we speak, I shook the mouse around expecting to see the magic...it actually slowed down the process. It was javascript though.

[Silly-V]

Try doing this test with:

* GPU preview on

* GPU preview off

* GPU preview on & Outline View

* GPU preview off & Outline View

It would be interesting to see if something that the user can change in the UI could have an effect on this issue!

[CarlosCanto]

when using js, outline view and full screen definitely improve performance. The reason, less UI and Art to redraw.

[matthewsjc1]

It was the same result with CPU as with GPU.

I tried outline mode and BAM! It processed the entire document in around a second (even faster than moving the cursor)! Great suggestion!! Thanks!

[matthewsjc1]

Oh wait. It's only if the cursor is moving over the Illustrator window that it processes super fast in outline mode. As usual, if the cursor is still, it processes at the normal slow rate.

[matthewsjc1]

Ya, it's still doing the same thing, just sped up some due to the lack of redrawing the document.

Wish I could figure this out. Would be incredibly useful.

[CarlosCanto]

awesome! 

does it help if you shake up the mouse programatically?

[matthewsjc1]

I haven't tried yet.

[matthewsjc1 · Accepted solution]

I found a solution. I ended up just slightly changing the document view's zoom factor in each 'for' loop iteration. This causes the same change as moving the mouse over the window (I'm assuming some sort of redraw/update) and makes the app process at full speed.

[CarlosCanto]

thanks for sharing your findings!! this could be real useful.

[CarlosCanto]

but just to be clear, this fast performance finding is through COM right?