Lagging silverlight app - silverlight

I've been playing around with Silverlight 5 and started putting together a little game. It's nothing special and it's purely to just play around.
If you look at the link below you'll notice that it's lagging a bit.
Link(Just use the arrow keys): http://www.netauto.co.za/WIP/GameTest.html
Basically I'm using a Storyboard to scroll the road and move the cars on the screen with every tick. At first I used the CompositionTarget.Rendering, but I was having the same problem. So I thought I'll try a Storyboard, but it made no difference.
There is a second timer that adds a vehicle in a random lane with every tick. They get removed once they go off screen. Disabling this timer makes no difference.
CPU usage is almost none. Also tried it on another PC and it was exactly the same.
I would post some code, but there's quite a bit of it and as I'm just fooling around it's a bit of a mess 0.o
Any ideas on how I can move the objects around without that lag?
I'm using Silverlight 5.
Thank you

You can try to use BitmapCache on the scrolling road and cars, if you are not already. This can cut down on the traffic to the GPU.
More links: One, Two.

Related

Fanned out cards in WPF- performance issues

In my WPF app I have a control representing a pack of 20 cards (each about 150x80 px) that fan out in an arc, so they're all slightly overlapping in the centre of the arc. When the control is added there's an animation to fan them out.
After that, the fan/control can be moved around, and when the user hovers over a card it expands and then goes back to normal size when they move off it.
This all works fine, but has a noticeable effect on performance- everything is very jerky, presumably because when other things move all the overlapping stuff and transforms in the control are being constantly recalculated/redrawn.
Any suggestions for how I can improve performance while still keeping individual cards in the fan responsive?
To find the source of the slowdown you need to profile.
Try to find out whether or not WPF is switching back to software rendering or not.
After that try to run on a different computer with other (better) hardware/graphics card.
If it doesn't get any better there might be errors in your app.

How to know why an animation stutters?

I have a few fairly simple animations (moving text around, moving ellipses etc.) and running in full screen (1920x1080 minus the task bar) the WPF Performance Suite reports a good framerate around 50 FPS throughout the animation. Dirty Rect Addition is somewhere around 300 rect/s, the SW frames are between 0 and 4 and the HW frames are between 3 and 5. Video memory usage is around 80 MB.
Problem is that the animations stutters every other half second. It is definitely not fluid :-(
My machine is a new Dell laptop XPS 15 with the GeForce GT 435 with 2GB memory. - The drivers are up to date. (The same behavior occurs on my netbook (in full screen) as well so I don't think it is hardware related.)
If I make the window smaller the stutter goes away.
The stutter occurs with the simplest of animations - even with just a couple of elements but adding more elements certainly makes it more noticeable.
How can I find out what causes this stutter?
When I think of it, I have not actually seen any WPF animations which run smoothly in full screen. Is this even possible?
Have you tried to set a lower "max frame rate" to the animation?
<Storyboard Timeline.DesiredFrameRate="10">
<!-- ....blah blah blah -->
</Storyboard>
If your animation is causing massive recalculation of child or parent elements, changing the DesiredFrameRate will have a cascading effect on the number of calculations made by the system.
Also, check out the "Remarks" section of this link. It explains why/when you should use it.
If setting a lower frame rate fixes your stuttering, then you need to consider simplifying your XAML to limit the amount of recalculation needed at every frame of your animation (limiting the number of child or parent objects resized - or affected in any way - by every frames/changes made by the animation.
You might want to also check out the "WPF Performance Suite". It is an awesome set of tools to determine what exactly is going on in your WPF app, seeing which parts of your window are being repainted and when, and the CPU usage of each of your XAML elements!
Hope this helps!
Patrick,
I have no answers. All I can do is provide some solidarity. I'm trying to animate an ItemsControl. The concept is pretty simple, really. I've got a ListView and in the ListView I have a GridView. I want the items in the GridView to to smoothly go from one row to another row as the underlying list is sorted so that, for example, a sorted list will stay sorted as the values in the list change.
I've noticed this: animation on moderately complex controls is a CPU hog. The stuttering I'm pretty sure is simply related to the CPU being maxed out (I noticed you didn't provide the CPU graph on your dump above). Keep the CPU around 50% and the animation appears smooth, above 75% and you get these stutters.
Still working on the problem, but I think it goes deeper than my code.
Don
I had a similar issue where it was stuttering, nothing really major it just looked like little stutters here and there while I ran the program. On a hunch, I shut down Google Chrome while it was running and that fixed it,the scrolling became completely smooth...
So my advice would be if you have any internet browsers open check to see if closing them out fixes the problem.

WPF tabswitch/ render takes too much time

I have a WPF application with many tabs..
in one tab.. i make a verycomplex vector drawing consisting of thousands of drawing visuals.. (this represents a machine and all elements need to be interactable..)
It takes 3/4 seconds for drawing this for the first time..After the first draw it should be done..
The problem is if i switch to another tab and comeback, it takes atlease 2,3 seconds to show the tabpage with drawing again.. Since there is no redraw, why should it take so much time..?
If the component is not going to change, you could call Freeze() on it to mark it as done. Without trying it out I don't know if that would help, but you could give it a shot.
Not all objects are Freezable. Check out the MSDN documentation for more info:
http://msdn.microsoft.com/en-us/library/ms750509.aspx
Another thing you could try would be rendering the vector art to a bitmap, and displaying that. Maybe it makes you feel icky to lose the vector precision, but if you know it's not going to change and it will look the same, what's the harm? (If you support printing or something that will require a hi-res version, you could always switch back for that operation.) For info on how to convert a UIElement to a bitmap, check out:
http://msdn.microsoft.com/en-us/library/system.windows.media.imaging.rendertargetbitmap.aspx
Another possible solution: You don't really explain what kind of interaction you are doing with the elements, but if all you want to do is zoom and pan, a RenderTransform may be good enough (which is more efficient than a LayoutTransform and/or moving all the elements individually). I haven't played around with combining Freeze() and a RenderTransform, but you may be able to get the desired zooming while reducing the amount of layout WPF has to do.

Prevent WPF stutter / dropped frames

I've written a simple game-like app in WPF. The number of objects drawn is well within WPF capabilities - something like a few hundred ellipses and lines with simple fills. I have a DispatcherTimer to adjust the positions of the objects from time to time (1/60th of a second).
The code to compute the new positions can be quite intensive when there are lots of objects, and can fully load a processor. Whenever this occurs, WPF starts skipping frames, presumably trying to compensate for the "slowness" of my application.
What I would much rather happen is for all the frames to be drawn anyway, only slower. The dropped frames do not add any speed - because visual updates were pretty quick anyway.
Can I somehow force WPF to have my changes to the visuals be reflected on the screen regardless of whether WPF thinks it's a good idea?
Unfortunately I don't think there's anything you can do about this, although I will happily be corrected! WPF is designed to be an application creation framework, not a games library, so it priortises application performance and "usability" over framerate. This actually works very well when producing applications as it allows you to use quite rich animations and effects while maintaining perceived performance on lower end systems.
The only thing I think you might be able to try is push your movement code's Dispatcher priority down slightly to below Render (Loaded is the next one down) using something like:
this.Dispatcher.BeginInvoke(DispatcherPriority.Loaded, MoveMyStuff);
I don't have any kind of test harness to verify if that will help though.
This issue was fixed by using a Canvas with an OnRender override instead of creating and moving UIElements. This does mean that everything needs to be drawn by hand in OnRender, but it can now run at any FPS consistently, without skipping any frames.

How can I manipulate a RagDoll made with farseer physics in Silverlight?

I made a ragdoll similar to the one in this demo. This rag doll will be used for a turn based rpg game where the physics will be used for animations such as character taking damage, dying, falling down, etc.
What I am pondering at the moment is as how should go about this, should I stick the rag doll by the head to the background (leaving the body dangling) and basically throw around its body parts around as to simulate punching etc (as shown in Fig 1), or stiffen the joints and statically rotate and move the body parts for the actions taken(as shown in Fig 2), and when it comes to the character dying(or a similar action) just loosen the joints and let the rag doll fall down. Or is there a better way to go about doing this?
I am new to farseer physics and don't even know if what I mentioned is even possible or overwhelmingly hard to do.
Illustration http://img3.imageshack.us/img3/8681/charactermovementrg5.jpg
Please note that the red line in the figures represents the character's arm
Not sure that ragdolls are the way to go here, if you want animations. But if you do want to use them, I'd lock the feet to the floor and have some rotation springs in the joints so that when no forces are applied, the body stands upright. Then if it gets a hit, it'll kind of bend over, but should rebound to it's stand-up state afterwards (you may have to help it along the way back, e.g. apply some forces/torques until it's back where you want it).
For animations, such as the character punching, you could perhaps apply a spring joint (I think that's the name). Connect it to the fist and the destination, and the arm should automatically move there. You could do the same with a kick, just release the lock on that foot. However, I think it might be hard to get it to look right. On the other hand, it would look unique to other games, even though it might look kinda funny.
If you're skilled, you might wanna create an animation editor and save an animation as a sequence of forces and torques that need to be applied to limbs in order to get them to where and when they should be.
I think a better approach is to have an animated sprite played, rather than going through joint manipulation .
Maybe you can use some RotateTransform implementations to articulate arms and legs.
For sure animated sprites are the best, and painless, way of doing this.

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