I am creating a game in which small pictureboxes move quickly across the screen. My monitor's refresh rate is 144Hz and it works fine, but when I put it down to 60Hz on some frames the picture box cant be seen or gets clipped.
Any way to alter the FPS the window runs at to avoid this clipping?
(i assume it rins at the same refresh rate as monitor)
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I am working on a project using SpriteKit to present simple shapes (SKShapeNode and SKSpriteNode) on the screen and move these shapes around in a predefined way.
I am interested in obtaining a very smooth motion, even for fast moving shapes (The code runs smooth for a couple of hundreds shapes and most of the time I only need less than 10).
I am quite satisfied with the motion smoothness for slowly moving objects on my macbook air and imac (60Hz displays and 60fps reported by showFPS in the SKView), however fast moving shapes create artefacts.
For that reason I would like to display the scene on a 120Hz monitor. I have scoured stackoverflow for a solution and only found solution to reduce the framerate from 60fps to 30 and 15 fps using frameInterval, but I haven't worked out how to obtain something higher than 60fps.
I have tried connecting my mac to a 85Hz CRT monitor (refresh rate set up in System Preferences to 85Hz), but my SKView still runs at 60fps.
Is there a way to access the EDID information of the monitor programmatically through SpriteKit? Is it possible to run an SKView at more than 60fps?
Thanks in advance
I'm having a strange and irritating problem on WinRT Surface tablet when using DirectX (hosted in BackgroundSwapChainPanel). Basically once in a while (like once a day, or few times a week / while testing for few hours every day), half of my 3D scene goes black, like on the picture below (cut vertically or sometimes horizontally):
http://www.zurawcli.vot.pl/dxProblem.JPG
While this happens, the DirectX is still rensponsive and i have full control of the app.
I don't think posting code makes any sense ( i'm simply using standard SwapChain and resizing viewport and back texture whenever screen size changes - actually getting screen size from Core Window). This only happens once in a while : ( when i try to explicitly force this - like by splitting screen between two / switching between apps / and so on, I CANNOT repeat this error - viewport always resizes correctly. Then sometimes just using the app, this will happen.
Did anybody had any experience similliar to this ? Any ideas what is causing this ?
Thanks in advance,
cheers
I am using CADisplayLink to draw frames using the EAGLView method in a game at 60 times per second.
When I call UIView animateWithDuration: the framerate drops down to exactly half, from 60 to 30 fps for the duration of the animation. Once the animation is over, the fps rises instantly back up to 60.
I also tried using NSTimer animation method instead of CADisplayLink and still get the same result.
The same behavior happens when I press the volume buttons while the speaker icon is fading out, so it may be using animateWithDuration. As I would like to be able to handle the speaker icon smoothly in my app, this means I can't just rewrite my animation code to use a different method other than animateWithDuration, but need to find a solution that works with it.
I am aware that there is an option to slow down animations for debug on the simulator, however, I am experiencing this on the device and no such option is enabled. I also tried using various options for animateWithDuration such as the linear one and the user interaction, but none had an improvement.
I am also aware I can design an engine that can still work with a frame rate that varies widely. However, this is not an ideal solution to this problem, as high fps is desirable for games.
Has someone seen this problem or solved it before?
The solution to this is to do your own animation and blit during the CADisplayLink callback.
1) for the volume issue, put a small volume icon in the corner, or show it if the user takes some predefined touch action, and give them touch controls. With that input you can use AVAudioPlayer to vary the volume, and just avoid the system control altogether. you might even be able to determine the user has pressed the volume buttons, and pop some note saying do it your way. This gets you away from any animations happening by the system.
2) When you have an animation you want to do, well, create a series of images in code (either then or before hand), and every so many callbacks in the displayLink blit the image to the screen.
Here's an old thread that describes similar drops in frame rate. In that case, the cause of the problem was adding two or more semi-transparent sprites, but I'd guess that any time you try to composite several layers together you may be doing enough work to cut the frame rate, and animateWithDuration very likely does exactly that kind of thing.
Either use OpenGL or CoreAnimation. They are not compatible.
To test this remove any UIView animation, the frame rate will be what you expect. Add back UIView animation, it will drop to 30fps.
You said:
When I call UIView animateWithDuration: the framerate drops down to exactly half, from 60 to 30 fps for the duration of the animation. Once the animation is over, the fps rises instantly back up to 60
I dont know why your not accepting my answer, this is exactly what happens when you combine UIView animation with CA animation not using a UIView.
I have a situation in which I ask and get a double-buffering OpenGL context, but when I draw in it, both the front and back buffer are affected. The draw buffer is set to the back buffer (And only the back buffer). If I look in OpenGL Profiler, I do see all that: the value for GL_DRAW_BUFFER (GL_BACK) and the actual back and front buffer being drawn to.
Since I'm working with an NSWindow that has a backing store, We do not see any of this happening on the screen. The problem is that I'm getting screenshots of this window with CGWindowListCreateImage. This function seems to be fetching the image from the front buffer, and not from the screen buffer (Wherever that is...). So the image returned is incomplete: it only contains the elements that are drawn at the moment it is grabbed, even if no flush has been called.
There is a utility in the mac developer package called Pixie. It basically grab the screen at the mouse position, and display it zoomed in so you can analyze it. This program has the same behavior than calling CGWindowListCreateImage: you can see incomplete images. So I guess the problem is not with the way I use CGWindowListCreateImage, but rather with my window or my display...
Also, It does not seems to happen all the time. Not every windows show this behavior, and even for a given window, it seems to come and go, especially if I move the window to a different screen (In a dual display).
Anyone faced this before?
I'm currently running into a problem regarding animation in OpenGL. I have between 200 and 10000 gears on the screen at a time all rotating. When the window is not in maximized view, my CPU runs at about 10-20 % consistently. No spikes, no stuttering in the animation, it runs perfectly smooth regardless of the number of gears on screen. When I maximize the window though, everything falls apart. My CPU maxes out, I begin getting weird spikes in CPU usage, the animation begins stuttering as a result, and it just looks really ugly, even when I have only 200 gears on screen.
My animation technique looks like this:
While Animating
Calculate current rotation angle based on a running timer
draw Image
call glFlush()
End While
If it helps, I'm using the Tao framework in VB.net. I'm not performing any other calculations other than the ones to calculate the rotation angle mentioned above and perform a few glRotateD and glscaleD in the method to draw the image.
In addition, I guess I was under the impression that regardless of the window size in an orthographic 2-dimensional drawing that is scaling on resizing of the window, the drawing time would always take the same amount of time. Is this a correct assumption?
Any help is greatly appreciated =)
Edit
Note that I've seen the animation run perfectly smooth at full screen before. Every once in awhile, OpenGL will decide it's happy and run perfectly at full screen using between 10-20% of the CPU (same as when not maximized). I haven't pinpointed what causes this though, because it will run one time perfectly, then without changing anything, I will run it again and encounter the choppiness. I simply want to pinpoint what causes the animation to slow down and eliminate it.
I've run a dot trace on my program and it says that the swapBuffers method is using 55 % of my processing time even though I'm never explicitly calling the method. Is the method called by something else that I can eliminate, or is this simply OpenGL's "dead time" method to limit the animation to 60 fps?
I was under the impression that regardless of the window size in an orthographic 2-dimensional drawing that is scaling on resizing of the window, the drawing time would always take the same amount of time. Is this a correct assumption?
If only :)
More pixels require more memory bandwidth/shader units/etc. Look into fillrate.