questions about chromeos multi-touch

[Ruidong Xu]

I understand from the official information available that chromeos supports up to 10 points of multi-touch.I have recently been doing a technical feasibility analysis of the product and have come across some problems. I would be very interested in getting answers here.

The first question:

I can get 20 simultaneous touches on my custom Android whiteboard software, but when I install the multi-touch test software on chromeos, I can only get a maximum of 16 on the same screen. Is this a problem with the chromeos limitation ? I am desperate to know why this is ? Pictures 1 and 2 are live pictures of my tests,picture 1 is from my custom Android system, picture 2 is from my chromeos test, please help me !

The second question:

I am currently trying to design a product in Chromeos and need to support 20 point touch, how do I get technical support ? Who should I contact ? My contact information is cooki...@163.com . I look forward to working with you !

[Andrew Melanson]

Give me a little to check into this and will help you as much as I can ,I just want to make sure you pointed in the right direction for your problem.

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[Ruidong Xu]

Thank you very much and I look forward to your help!

[Harry Cutts]

On Monday, March 6, 2023 at 2:57:16 AM UTC Ruidong Xu wrote:

I understand from the official information available that chromeos supports up to 10 points of multi-touch.I have recently been doing a technical feasibility analysis of the product and have come across some problems. I would be very interested in getting answers here.

The first question:

I can get 20 simultaneous touches on my custom Android whiteboard software, but when I install the multi-touch test software on chromeos, I can only get a maximum of 16 on the same screen. Is this a problem with the chromeos limitation ? I am desperate to know why this is ? Pictures 1 and 2 are live pictures of my tests,picture 1 is from my custom Android system, picture 2 is from my chromeos test, please help me !

A few questions here:

• What hardware are you using, both for the test where you get 20 touches with your custom Android software and when you get only 16 on ChromeOS? (i.e. what display, what Android or ChromeOS device, and how are the two connected?)
• What multi-touch test software did you try on ChromeOS? Is it an Android app, Web page, Linux app...?

The second question:

I am currently trying to design a product in Chromeos and need to support 20 point touch, how do I get technical support ? Who should I contact ? My contact information is cooki...@163.com . I look forward to working with you !

chromeos.dev is the official ChromeOS developer support site. I notice they recently posted an invitation to join the Discord, where you can apparently contact developer advocates.

[Nick McSherry]

Just a guess, but maybe chromeos is limiting to the amount threads available on on the hardware?

[Ruidong Xu]

We are using a 75" screen with a hardware touch frame that we developed in-house and supports 20 point touch on both android and windows.
The chrome device is a BC5000 series AOPEN Chromebox Commercial2 and the connection cable is a USB touch cable, see the picture below. The same touch frame and touch connection cable allows us to get 16 point touch on chromeos.
I have a question and I would like to confirm if chromeos puts restrictions on multi-touch. For example, I can't get 20 points of touch on chromeos no matter what hardware I change.
The Chromeos uses the multi-touch test from the Google App Store, which explicitly supports 20-point touch in its description.

[Harry Cutts]

Thanks for the info! Having a quick look in the touchscreen handling code, the maximum number of touches supported should be 20. Could you try the touchscreen with a Web-based tester, like this one or this other one? I'm wondering if this limitation is specific to Android apps running on ChromeOS.