I'm using opengl es 3.0 API with the android studio ndk to create apps.
But I've encountered a very huge problem. I've created a demo app, all it does it change the background color of the screen from white to black and vice versa, every frame. And so when I go to minimize this app, I still see it rendering the background, mostly at the edges of the screen, and not in full color but still very strongly apparent. And it doesn't go away when I close the app, when I restart the device, or when I run "kill apps" on it. Only a factory data reset fixes the issue, so it's not easy for me to debug this.
This is the relevant code that I'm using for when the app is minimized and receives the APP_CMD_TERMINATE event:
eglMakeCurrent(engine->display,EGL_NO_SURFACE,EGL_NO_SURFACE,EGL_NO_CONTEXT);
eglDestroySurface(engine->display,engine->surface);
engine->display = EGL_NO_DISPLAY;
engine->surface = EGL_NO_SURFACE;
I've error checked that eglDestroySurface() is successful.
And I've put debugging messages in to make sure that the main draw loop is NOT executing when the app is minimized. But the problem persists and I don't know what to do about it. Thanks for any help.
UPDATE: well, no one has responded, and I still don't know what to do. Could it be related to threads?
UPDATE: Still can't determine what it is, but for some reason it's messing with the System UI. Willing to upload my entire source code somewhere if someone would be willing to go through this with me, as I'd really like to be able to continue working on my game engine.
Is it the "Strict Mode" developer option on the device settings, perhaps?
That one flashes the screen if an app is blocking.
It would explain why a factory reset changes behaviour.
The answer is not a solution here. The above comment by the user columbo was correct.
I've demoed switching from black to white at high framerates on 3 different android devices, and also my Linux Desktop, all via the openGL api, and it has exhibited this issue on all the devices. So what he said must be correct: this is a problem with LCD monitor technology itself. Interestingly, doing completely random colors does not cause this problem.
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I'm from Ukraine, so I immediately apologize for my crooked English. I got one very incomprehensible problem with which I can not figure it out. I have created a mobile application for Android and IOS. Absolutely normal application. I tested it on the emulator on several phones. But on one of them, the app didn't look like itself. For some reason it became dark and looked strange (I attached the screenshots). The normal version is white-green, this version was dark. I can't figure out what is the reason. Immediately I will say that the phone is normal and the light theme is enabled on it, the phone has standard settings. And everything else on this phone except this application is displayed normally. Please tell me what is the reason
I tried to change the themes and settings of the phone, and found out that the problem is definitely not in them
enter image description here
We have many phones using Android Management with kioskCustomLauncherEnabled on. When opening applications occasionally they will minimize as if the home button was pressed. We've observed this on Pixel 1, Pixel 3a and Pixel 4a phones. We've disabled all gestures thinking that might be related but it still occurs.
Is this a bug of the phone's kiosk mode? Is there a workaround?
Hi there and thanks for your question,
I think it's a bit difficult to answer without looking at your dedicated device policy. I haven't heard personally of such a bug but maybe it could be a behaviour you set on your policy? Generally, you would use kioskCustomLauncherEnabled if a device requires users to access one or more apps from the home screen triggering a go back to home type of behaviour while keyguardDisabled would trigger the device to stay unlocked. You will also want to disable a maximum amount of settings available to the user.
Theo L
Android Enterprise
This appears to have been a Pixel 3A problem. One of the recent system updates a few months ago seems to have made the problem go away. Doesn't appear to still be an issue
I have a graphics application that occasionally displays incorrectly after a sleep / wake cycle.
I'm wondering if there is something I should do on the Sleep or Wake events. I'm capturing these events already, because I hide the cursor in the app, and when the app wakes the cursor appears and has to be re-hidden. I'm creating my images with [[NSBitmapImageRep alloc ]initWithBitmapDataPlanes:outplanes, doing lots of bit manipulation on multiple images. I display the image full screen. Xcode 7.1, OSX 10.10
The error I get is a shimmering on the display as if my merge routines are using the wrong data.
I was assuming the sleep took a snapshot of all my data, including whatever is on the stack? It's hard to reproduce the problem, but my App is going to be running every day in a public space and uses the scheduler to sleep each night and autowake in the morning.
Should I reinitialise all my variables on a wake?
I can't see anything on the apple docs about actions you should take on these events.
It should not be necessary to worry about this. If it is, that is likely to be either a bug in your app, or a bug in Apple's code. Indeed, the cursor issue you mention sounds like a bug to me, and you should log a bug in Apple's bug reporter about that. Sleep/wake should be entirely transparent for apps that don't have a specific reason to care. You will need to try to pin down the issue you are seeing, somehow, and diagnose it.
I am in the process of porting a Flash Player-based game over to the Desktop (OSX and Windows) via Adobe AIR (3.1). The porting to AIR itself has gone rather smoothly. The one wrinkle I've been dealt is that the game will be distributed over the Steam network. In order to interact with the Steam Client, I've had to write a native extension to expose the Steam SDK APIs to AS3. The native extension support has been implemented for both platforms, and I have the application launching and communicating with Steam as desired.
The area I've run into trouble is dealing with Steam's Overlay, which renders overtop of games when it is activated. Essentially, when a game is launched, the Steam Client suspends the process in order to hook its Overlay library up to either D3D or OpenGL. Initially, the Overlay failed to appear at all as the AIR application descriptor had the default rendermode set to "auto." However, once I switched the rendermode to "gpu" the Overlay would appear as desired.
On the OSX side of things, everything works as expected. I can toggle in and out of the Overlay just fine. On the windows end of the spectrum, I've hit a bit of a problem when I activate the Overlay. Specifically, when the Overlay is enabled (it's rendering overtop of the game) and I either move the mouse or generate keyboard input, both the Overlay and the game both "freeze" (rendering stops) for 2-3 seconds. Additionally, I have noticed that when I open the Task Manager with the game running, the cpu usage is roughly 75-80%. The cpu usage remains the same when I first active the Overlay (which is desired). However, when I move the mouse cursor or press a key on the keyboard, the cpu usage drops to roughly 1%. This problem has occurred on 4 of 5 windows machines (2 XP, 3 Win 7) we've tested on. Naturally, I first contacted Valve about the issue since this only occurs when the Overlay is enabled. I've uploaded both the OSX and Windows builds for their devs to debug; however, my contact suggested I find out more about AIRs rendering/input as well.
Here is a snippet of a post with a Steam Dev detailing how the overlay works:
"The requirements for the overlay on Windows are as follows:
Game must use D3D7, D3D8, D3D9, D3D10, D3D11, or OpenGL
Game must call D3D Present() or OpenGL SwapBuffers() on a fast regular basis (these calls are hooked by the overlay and give it opportunity to do work). For instance 2D games that only call these functions when mouse movement occurs or graphics on screen actually change rather than every frame will not function well.
Game should use standard Win32 input messages, raw Win32 input messages, or DirectInput for input and the overlay will then detect hotkeys and hide/block input events from the game when active.
It sounds like your game may violate #2 and stops calling Present/SwapBuffers sometimes when the overlay is active. This may happen if you call these functions in response to user input which is now blocked due to the overlay being activated. You should guarantee you keep pumping frames and swapping at a regular interval even if input events aren't occurring."
After a little more prodding, the Valve devs profiled my application to determine if there was any specific problem occuring with the Game Overlay. Unfortunately, they were unable to find anything going on in the Overlay itself. This pretty much means that AIR on Windows doesn't like that the Overlay is blocking Win32 input messages. Here is the Valve dev's response:
"I got your depots and did some testing. Nothing unusual happens in the overlay. Profiling your app with xpref while the issue occurs and taking some minidumps to check callstacks it looks like the app just blocks up completely and uses zero CPU during the time it is blocked, when it happens it calls Present() only at roughly 1 second intervals until it recovers (maybe there is a 1 second timeout somewhere in the AIR code). It's hard to get much detail since I don't have any symbols for the AIR runtime libraries.
It does however look like this is somehow related to input state and AIR being unhappy with win32 input messages stopping. If I change our overlay to not block any input at all once activated (which obviously has some pretty big problems for usability, but just for testing purposes.) then the issue does not occur. It's possible that the AIR code has some weird logic where if it's seen some specific WM_WHATVER message it's expecting another right after and blocks on it waiting somehow.
Hopefully you can work out on your side or with Adobe as to why the application behaves badly in these situations and starts blocking and not presenting at regular intervals."
I've posted on the Adobe forums, but haven't had any such luck over there. Mainly, I'm hoping that someone has either dealt with this before or has an idea about how I could possibly get around the issue. Any suggestions, comments or thoughts would be greatly appreciated!
As it turns out, there is an bug deep in AIR core framework that is the root cause of this issue. Adobe has confirmed the bug, and they are working on a fix for the Cyril (AIR 3.3) release. The status of the bug (#3089755) can be viewed in the Adobe AIR bug list.
In the short-term, I was forced to detect Windows messages that were being consumed by the SteamOverlay, and pass on fake messages to prevent AIR from locking up. I accomplished this by using the Windows API SetWindowsHookEx along with the WH_DEBUG and WH_GETMESSAGE hooks. This is definitely not a desirable approach, but was needed in the short-term until Adobe releases a fix.
Quick question -- if I code something to respond to "MouseLeftButtonDown" such as the pushing of an image, if I leave the code the same way when I ship the app, will this directly translate to the user pushing their finger down on the same spot, and thus fire the code?
Do I have to change the MouseLeftButtonDown to the gesture listener for this to translate, such that MouseLeftButtonDown is only used in place of non-touch monitors when coding to test things?
THanks!
As corrected by Matt in the comments, the MouseLeftButtonDown event is not the same as an image tap. However, the result would be the same in that if your code works on the emulator, regarding the tapping, then it should work on the device.
You should try and get your app running on a device though as there can be things easily overlooked in the emulator. For example, performance can decrease on your phone since it's likely to be quite a lot less powerful than your PC. Therefore, if your app is performing fine on your PC (emulator), it doesn't necessarily mean you'll get the same speeds on the device.