Upgrade StorageDebug ID: D918391774 [Android App: freehand draw slow and wrong rendering]
In the Android app, on some devices, the freehand draw is very slow and letters/characters after the first are rendered with considerable delay, and often curves are turned into straight lines, which makes the letters unrecognizable. (This has been mentioned in https://forums.zotero.org/discussion/124295/android-beta-freehand-drawing-in-pdf-slows-down-occasionally-crashes-app and https://forums.zotero.org/discussion/125665/bug-android-app-pdf-annotation-delays-between-input-and-completion-of-action; I am opening a new thread *only* for this issue.)
This problem is 100% reproducible. The problem is triggered by lifting the pen from the screen. In other words, there is no problem if I draw a very long, possibly winding, curve, but the moment I lift the pen from the screen, subsequent writing shows long lag and is not processed correctly (curves seem to be converted to lines).
This can be seen easily if I write "Hello". If I manage not to lift the pen, it is fine. However, if I lift the pen to draw the first horizontal "-" in the "H", the rest of the "H" and the remaining letters are not drawn correctly (unless, as I say, I write at a pace slower than 1 letter per about second and a half). (The same thing can be seen with other examples; write a Greek theta, and lift the pen for the horizontal "-", or two successive "i", etc.)
Indeed, this pattern can be observed in the two videos posted by @jhimmelreich in thread https://forums.zotero.org/discussion/124295/android-beta-freehand-drawing-in-pdf-slows-down-occasionally-crashes-app (https://streamable.com/dtte0o, https://streamable.com/u5cd98).
More details:
- Character size (the size of the letters I draw) makes no difference.
- Color and size of the annotation (as selected from the annotation menu) make no difference.
- Zoom level makes no difference.
- This happens regardless of PDF (large or small, previously annotated or not).
- Palm rejection is working fine.
- This does not happen in other PDF apps (Xodo, Foxit, browser's PDFs when using Zotero Web Library).
- Changing the S-Pen's Air actions makes no difference.
This bug is possibly hardware-specific, but affects different devices:
- The details above are from a Samsung Galaxy Tab S7 FE with Android 14, One UI version 6.1, and Zotero 1.0.0.0-186.
- On an Android phone that has no stylus/pen, handwritting with the finger does NOT show this problem.
- Unfortunately, I cannot disable the pen/stylus entry in the Tablet (this does not seem possible in the Samsung galaxy Tab S7 FE).
- Reports from other users are from other devices (@adrianvaneeden: Samsung Galaxy S23 Ultra, Samsung Galaxy Note S10 FE in https://forums.zotero.org/discussion/125665/bug-android-app-pdf-annotation-delays-between-input-and-completion-of-action; @jhimmelreich: Daylight DC-1, @malev: Boox 10.3 , in https://forums.zotero.org/discussion/124295/android-beta-freehand-drawing-in-pdf-slows-down-occasionally-crashes-app)
I've tried to check if this is because of CPU limitations; I don't know how to check CPU usage per application in Android (I think it is not possible, unless the device is rooted?), but using an app that displays overall CPU usage during the operation did not suggest that the CPU was maxed. RAM not an issue either, as there were a few GB free.
But since it is impossible for me to write without lifting the pen, this bug prevents me (and I guess other users with affected devices) from adding freehand annotations (unless I am willing to writing a single character at a pace of about one per second and a half). And freehand writing is an essential part of my PDF reading/annotating with Zotero.
This problem is 100% reproducible. The problem is triggered by lifting the pen from the screen. In other words, there is no problem if I draw a very long, possibly winding, curve, but the moment I lift the pen from the screen, subsequent writing shows long lag and is not processed correctly (curves seem to be converted to lines).
This can be seen easily if I write "Hello". If I manage not to lift the pen, it is fine. However, if I lift the pen to draw the first horizontal "-" in the "H", the rest of the "H" and the remaining letters are not drawn correctly (unless, as I say, I write at a pace slower than 1 letter per about second and a half). (The same thing can be seen with other examples; write a Greek theta, and lift the pen for the horizontal "-", or two successive "i", etc.)
Indeed, this pattern can be observed in the two videos posted by @jhimmelreich in thread https://forums.zotero.org/discussion/124295/android-beta-freehand-drawing-in-pdf-slows-down-occasionally-crashes-app (https://streamable.com/dtte0o, https://streamable.com/u5cd98).
More details:
- Character size (the size of the letters I draw) makes no difference.
- Color and size of the annotation (as selected from the annotation menu) make no difference.
- Zoom level makes no difference.
- This happens regardless of PDF (large or small, previously annotated or not).
- Palm rejection is working fine.
- This does not happen in other PDF apps (Xodo, Foxit, browser's PDFs when using Zotero Web Library).
- Changing the S-Pen's Air actions makes no difference.
This bug is possibly hardware-specific, but affects different devices:
- The details above are from a Samsung Galaxy Tab S7 FE with Android 14, One UI version 6.1, and Zotero 1.0.0.0-186.
- On an Android phone that has no stylus/pen, handwritting with the finger does NOT show this problem.
- Unfortunately, I cannot disable the pen/stylus entry in the Tablet (this does not seem possible in the Samsung galaxy Tab S7 FE).
- Reports from other users are from other devices (@adrianvaneeden: Samsung Galaxy S23 Ultra, Samsung Galaxy Note S10 FE in https://forums.zotero.org/discussion/125665/bug-android-app-pdf-annotation-delays-between-input-and-completion-of-action; @jhimmelreich: Daylight DC-1, @malev: Boox 10.3 , in https://forums.zotero.org/discussion/124295/android-beta-freehand-drawing-in-pdf-slows-down-occasionally-crashes-app)
I've tried to check if this is because of CPU limitations; I don't know how to check CPU usage per application in Android (I think it is not possible, unless the device is rooted?), but using an app that displays overall CPU usage during the operation did not suggest that the CPU was maxed. RAM not an issue either, as there were a few GB free.
But since it is impossible for me to write without lifting the pen, this bug prevents me (and I guess other users with affected devices) from adding freehand annotations (unless I am willing to writing a single character at a pace of about one per second and a half). And freehand writing is an essential part of my PDF reading/annotating with Zotero.