Curl -- corner doesn't always pick up

[moscow25]

With some side-work, I modified the XBPageCurl to allow me to turn over a poker-card from the top-right corner with a down or left finger-pull.

It usually works great, but since iOS7 release, in about 30% of the cases, the corner fails to pick up.

Has anyone else seen this, or have there been some changes I failed to pick up in the past few months? My version is heavily modified by several people w/r/t setup, but the core CurlView and DragView classes have remained undisturbed.

This is my favorite feature in a card game that's played by 1,000 people a day, so I'd love to get this working right close to 100% of the time. Thanks!
https://itunes.apple.com/us/app/abc-chinese-poker-open-face/id651409079

The view starts like this:

Then usually I can grab the corner and get a page-curl like this one. I have it set that that 70% pull-over, the card flips over completely.

But in many cases (but not all), the "drag me" corner disappears on holding, but the card doesn't drag.

If I release my finger, I go back to the start view. "drag me" comes back up, but still can't drag.

When I first implemented this, the error did not exist. I think it started appearing around iOS7 release. As usual, it's hard to debug intermittent errors...

[mops]

I guess, I have the same bug.
And sometimes, when I drag corner, I get error: OpenGL error: 0x506 :((

[moscow25]

I see. Do you get it in simulator, or just on the device?

Glad to know (sort of, sorry) that I'm not the only one getting an error. Would you care to share how you're getting this error? Since iOS7, or you've had it always...

I am very interested in fixing this. The 3D squeeze feature in my card game is very cool when it works correctly.

[mops]

On device.
I've tested it only on iOS7. And maybe reason in my viewToCurl, cuz I'm drawing by OpenGL on it. And maybe, it conflicts with XBPageCurl... Don't know...

[moscow25]

Thanks man. Hopefully the oracle! (XissBurg) might have a clue. I pinged him but no response yet. Probably an iOS7 thing...

I'm way out of my depth in OpenGL stuff. Unfortunately.