hiding movieclip, rendering performance - performance

I'm developing a rendering engine for a game i am currently building..
I have a main camera (rectangle) that determines what needs to be rendered (thing within it's boundaires)
I am using a bitmap rendering method for the background and that all works fine.
but for the character i am using a movieclip over the top.
when the character goes out of the camera's view is it 100% neccesary to set visible=false?
atm the game is running at 30 FPS (as intended) and everything is sweet, i just wanted to ask out of curiosity.
Is flash clever enough to not bother with movieclip outside of the scene boundaires?
Thanks in advance,
Rory

According to http://help.adobe.com/en_US/as3/dev/WS5b3ccc516d4fbf351e63e3d118a9b90204-7e3e.html Flash won't render if an object is outside of Stage boundaries:
Display list
The hierarchy of display objects that will be rendered as visible
screen content by Flash Player and AIR. The Stage is the root of the
display list, and all the display objects that are attached to the
Stage or one of its children form the display list (even if the object
isn’t actually rendered, for example if it’s outside the boundaries of
the Stage).

In my experience display objects added to the stage cause a performance hit even if they are not rendered.
Setting visible to false causes a much lower performance hit, but still a small hit.
Removing unnecessary display objects from the display list is a documented performance tip from adobe as well.
Of course, if you only have a few dislay objects it might not be worth the effort, but if we talk about large amounts of display objects I strongly recommend removing them from the display list.

Related

JavaFX DragView Image has lowered opacity compared to actual image... Can that be changed?

I have been working on using Drag and Drop with JavaFX, and one thing I notice is that items are given lowered opacity compared to their actual images, as well as the larger the image the made "Faded/transparent" the image gets. I am working on am application that can drag fairly large items which end up almost invisible when dragging, which defeats the purpose of using a DragView Image in the first place, and makes this unusable for larger items (the way I'm using the DragView I want the images to be a certain size compared to the scene in which I'm dragging onto).
My application essentially has 2 Windows (Stages) where the data is in one Stage and I get the item from a list and drag it onto the scene. The DragView image is a representation of the object going onto the scene, so when I drop the DragView Image, it gets dropped exactly into place on the scene, so the DragView is important to my overall application.
Just a NOTE: There is also backing data in my transfer in order to recreate the box, as well as additional data that gets transferred with the Drag and Drop.
I tried looking at the FX DragView Internal code but didn't find anything that sets the Opacity or anything like that, so one of my assumptions of "it's built into the OS" is something I keep thinking about, as lowered opacity is something I remember being built in, and when trying it it does happen, but very very slight, and not as bad as what I'm experiencing (Also possible that since the icons are much smaller they don't run into the "larger image opacity issue."
I am running Windows 7 64-Bit for those who are wondering.
My question is, is it possible to change the opacity settings of the Drag and Drop ImageView either via JavaFX or possibly Native with using something along the lines of JNI?
I don't have any example code at the moment, but can add if someone is interested, but I'm sure for those who know about Drag and Drop ImageViews should already know about the opacity.
Thank you all.

EaselJS and multi layered canvas system: performance tuning, game developing, event handling

I'm an engineer and we are currently porting our Red5 + Flash game into a Node.js + Easeljs html5 application.
Basicly: it's a board game, not an rpg. The layer system means we have multiple canvasses, based on functionally. For example there is a static background stage, with images. There is a layer for just the timers.
At default, all canvas size is 1920x1080, if needed we downscale to fit to the resolution.
The first approach used kinetic.js, but the performance fallen when the game got complex. Then we switched to easel, because it's abstraction level is lower, so we can decide how to implement some more function, not just use the provided robust one.
I was optimistic, but now it's starting to show slowness again, that's why I want to look deeper inside and do fine performance tuning. (Of course everything is fine in Chrome, Firefox is the problem, but the game must run smoothly on all modern browser).
The main layer (stage) is the map, contains ~30 containers, in each there is a complex custom shape, ~10 images. The containers are listening to mouse events, like mouseover, out, click. Currently, for example on mouseover I refill the shape with gradient.
Somehow, when I use cache, like the way in the tuts the performance get even worse, so I assume I'm messing up something.
I collected some advanced questions:
In the described situation when can I use cache and how? I've already tried cache on init, cacheUpdate after fill with other color or gradient, then stage.update(). No impact.
If I have a static, never changing stage cache doesn't make sense on that layer, right?
What stage.update() exactly do? Triggering the full layer redraw? The doc mentions some kind of intelligent if changed then redraw effect.
If I want to refill a custom shape with new color or gradient I have to completely redraw its graphics, not just use a setFill method, right?
In easel there is no possibility to redraw just a container for example, so how can I manage to not update the whole stage, but just the one container that changed? I thought I can achieve this with caching, cache all containers the just update the one that changed, but this way didn't work at all for me.
Does it make sense to cache bitmap images? If there are custom shapes and images in a container what is better? Cache the container or just the shape in container.
I found a strange bug, or at least an interesting clue. My canvas layers totally overlapping. On the inferior layers the mouseover listening is working well, but the click isn't on the very same container/object.
How can I produce a click event propagation to overlapped layers those have click listeners? I've tried it with simple DOM, jquery, but the event objects were far away from what canvas listeners wanted to get.
In brief, methods and props I've already played with bare success when tried tuning: cache(), updateCache(), update(), mouseEnabled, snapToPixel, clear(), autoClear, enableMouseOver, useRAF, setFPS().
Any answer, suggestion, starting point appreciated.
UPDATE:
This free board game is a strategy game, so you are facing a world map, with ~30 territories. The custom shapes are the territories and a container holds a territory shape and the icons that should be over the territory. This container overlapping is minimal.
An example mouse event is a hover effect. The player navigate over the territory shape then the shape is getting recolored, resized, etc and a bubble showing up with details about the place.
Basically, maximum amount of 1-3 container could change at once (except the init phase -> all at this time). Not just the animations and recoloring slow in FF, but the listener delay is high too.
I wrote a change handler, so I only stage.update() up on tick the modified stages and the stages where an animation is running (tweenjs).
In my first approach I put every image to the container that could be needed at least once during the game, so I only set visible flags on images (not vectors).
Regarding caching:
There are some strange caching-issues, somehow the performance can drop with certain sizes of the caching rectangle: CreateJS / EaselJS Strange Performance with certain size shapes
(2) Depending on how often you call stage.update();
(3)
Each time the update method is called, the stage will tick any
descendants exposing a tick method (ex. BitmapAnimation) and render
its entire display list to the canvas. Any parameters passed to update
will be passed on to any onTick handlers.
=> Afaik it rerenders everything if not cached
(4) Yes.
(5) No. (I don't know of any)
(6) If the content's of the container don't change often, I'd cache the whole container, otherwise the container will be reconstructed every frame.
I have a question though: Why do you use multiple canvases? How many do you use? I could imagine that using multiple canvases might slow down the game.
How many sprites do you use in total?
2: if your layer or stage doesn't change, don't call stage.update() for that layer (so it doesn't gets rerendered, gives me a much lower cpu!)
For example, keep a global "stagechanged" variable and set this to true when something has changed:
createjs.Ticker.addEventListener("tick",
function() {
if (stagechanged)
{
stagechanged = false;
stage.update();
}
});
(or do you already use this, as stated in your "update"?)
4: I found a way to update for example the fill color :)
contaier1.shape1.graphics._fillInstructions[0].params[1] = '#FFFFFF';
(use chrome debugger to look at the _fillInstructions array to see which array position contains your color)
5: I found a way to just paint one container :)
//manual draw 1 component (!)
var a = stage.canvas.getContext("2d");
a.save();
container1.updateContext(a); //set position(x,y) on context
container1.draw(a);
a.restore();

Does Direct2D use back-buffer?

Reading https://learn.microsoft.com/en-us/windows/win32/direct2d/comparing-direct2d-and-gdi :
Presentation Model
When Windows was
first designed, there was insufficient
memory to allow every window to be
stored in its own bitmap. As a result,
GDI always rendered logically directly
to the screen, with various clipping
regions applied to ensure that it did
not render outside of its window. In
contract, Direct2D follows a model
where the application renders to a
back-buffer and the result is
atomically “flipped” when the
application is done drawing. This
allows Direct2D to handle animation
scenarios much more fluidly that GDI
can.
The author says Direct2D uses back-buffer and by 'flipped' he meant swap-chain I guess. I created a simple demo that draw a rectangle at random location on mouse click. But previous rectangles are not cleared so it seems that it is drawn directly to the screen and does not use any back-buffer.
When you initialize the RenderTarget for your Direct2D operations you can specify in the second parameter the D2D1_PRESENT_OPTIONS option.
I think what confuses you is the D2D1_PRESENT_OPTIONS_RETAIN_CONTENTS and the fact that the buffer isn't swapped but copied.
That doesn't disprove the existence of back-buffers, it only means the back-buffer isn't cleared between redraws. Right observation, wrong conclusion!
If you increase the number of back-buffers in the chain, you'll start noticing flickering rectangles as you keep clicking, so you should always clear your back-buffer between redraws.
Direct2D indeed uses back-buffer.
Perhaps you forgot to clear your render target, which is the back-buffer, right after calling begindraw and so previous draws stayed there?

CALayer flickering when adding a foreground layer to IKImageBrowserView items with garbage collection on

I'm trying to implement a technique similar to the one in the ImageBrowserViewAppearance sample code from Apple (located here: http://developer.apple.com/library/mac/#samplecode/ImageBrowserViewAppearance/Introduction/Intro.html ), where CALayers are generated on top of the items in the IKImageBrowserView to customize the appearances of the objects in the image browser.
However, I'm getting a weird problem when I turn on garbage collection, and I can reproduce it in the Apple sample code. Simply turn on Garbage Collection in the target, and build and launch the ImageBrowserAppearance sample app. Then, add some photos to the image browser using the "Add Photos..." button.
Now, click on an empty portion of the IKImageBrowserView, and click and drag to start selecting multiple items in the browser view. As you drag the selection box around, you should notice that sometimes the pin and gloss overlay for some of the items flicker and briefly appear in the bottom-left corner of the IKImageBrowserView. All of the CALayers seem to do this occasionally, I've seen the white surrounding slide area flicker down into the bottom-left corner as well.
When I mimic the technique in my own code, I (not surprisingly) also can reproduce this badge flickering. However, this problem disappears when garbage collection is off.
Anybody have a clue what could be going wrong here? I'd like to use garbage collection in my app in conjunction with this technique, but the flickering is kind of annoying.
I bookmarked this a while back but Apple's changed the URL and the text. Fortunately I quoted it when I bookmarked it:
The Core Graphics APIs (Quartz 2D) see an approximately 25% reduction in drawing performance for applications compiled to use garbage collection.
That "25% reduction in drawing performance" text has been rewritten into a "slight overhead in code execution" and that was for 10.5. Perhaps Apple fixed it for 10.6. And you're talking Core Animation, not Core Graphics.
Still, Core Animation eventually has to talk to Core Graphics, and perhaps that performance issue hasn't gone away, and you're being bitten by it.
I fooled around with this a bit and can confirm I get the same behavior running the project with GC turned on. In fact, if you're patient enough and slowly change the selection one image at a time using the arrow keys, eventually it'll trigger the behavior and you can see the layers from one image in the view are displayed in the lower left corner instead of on top of the image. I haven't been able to find any sort of pattern as to when it happens, or any relation between which image is selected and which image has its layers missing. I'm assuming that for whatever reason, those layers are getting their frame origin set to {0, 0}, but heck if I know why.

Placing objects on scrolling background in XNA

How do I place objects that appear only if the background scrolls to a certain point?
Example- I have this long image that keeps scrolling using the technique above. However, after scrolling to part of the image, I want to add a platform there. How would I do that?
In general, you will probably need to save the locations of your objects in a file and then load that file at the beginning of the level (assuming you are making some kind of platformer game). You can do this by creating a class or a struct containing all the relevant information for the platform (position, size, texture, etc) and then using XML serialization to write an array of those classes/structs to a file.
Your level loader would then load and deserialize the level data, which would end up being a list of all the objects in your level (such as platforms). Now that you have the locations of your platforms in memory you have a couple different options on how to get them to the screen.
Draw all the objects (platforms) all the time, whether or not they are in the view of the camera. If your levels don't contain a lot of objects, this would be simple to implement.
Draw only those in the camera's view. Without knowing how you implemented the horizontal scroller, it's kind of hard to make suggestions for this part. Whatever mechanism you currently have to identify the boundaries of what part of the background to show could be used to determine which objects to draw as well.
I'm working on a game that scrolls vertically right now, and I needed a way to do something similar: place objects in a level and have them appear when the background scrolled to them. I used TorqueX 2D (free engine binaries if you've payed to develop for XNA) and its 2D scene editor to set this up pretty easily. I have my camera scrolling up, the background stays in place. When it gets to an object position defined in the XML level file it spawns the object in the level.

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