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Questions tagged [caemittercell]

The CAEmitterCell class is available in OS X v10.6 and later, and represents one source of particles being emitted by a CAEmitterLayer object.

The CAEmitterCell class represents one source of particles being emitted by a CAEmitterLayer object. An emitter cell defines the direction and properties of the emitted particles. Emitter cells can have an array of sub-cells, which lets the particles themselves emit particles.

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Initial particles from CAEmitterLayer don't start at emitterPosition

My goal is to make an explosion-like animation where many particles are emitted in a short duration. My problem is that CAEmitterLayer, when it begins emitting, adds "future" particles to make it looks like the animation has been running for a…
WaltersGE1
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Fading out emitter cells with Core Animation

I am creating a particle animation with CAEmitterLayer and CAEmitterCell instances. There is no problem with the animation but I want them to fade out slowly. I am using the code below but the particles disappear suddenly, no fade out animation…
Élodie Petit
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CAEmitterCell does not respect birthRate change

I would like to create a particle effect which is only emitting while the user touches the screen, but I cannot change the CAEmitterCell birthRate property once is set to a non zero value. I have a subclass of UIView, which sets up my CAEmitterLayer…
nekiTamoTip
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What is the proper way to end a CAEmitterLayer in Swift?

I've mostly seen examples of continuous emitters in Swift, and I've found one example in Obj-C by setting the birthRates of the emitter cells to 0.0, but it doesn't seem to work, so I must be doing something wrong. In my example, I can see the…
Chewie The Chorkie
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CAEmitterCell color property not working

I have some strange behaviour of CAEmitterCell color property or I don't understand it right. I have a cell let cell = CAEmitterCell() With content of simple .png file which is drawn black cell.contents = UIImage(named: "particle")?.cgImage And I…
pulp
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Changing CAEmitterCell properties of CAEmitterLayer after emission starts

When I first set up the emitter I can do this: self.cell = [CAEmitterCell emitterCell]; self.cell.yAcceleration = 20; ... self.emitter.emitterCells = [NSArray arrayWithObjects:self.cell,nil]; But say I create a timer that fires 5 seconds later, and…
soleil
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animating the CAEmitterCell Color property

I have a CAEmitterCell and I have set it up with a specific colour. The documentation says that this property is animatable, and I would like to animate this between a number of different colours for the different players in my game (all of whom…
Alan Taylor
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CAEmitterLayer: Using an @2x (retina) png image with CAEmitterCell

Using CAEmitterLayer, @2x (retina) images aren't being scaled property like they do elsewhere in iOS. The result I'm getting is the @2x version is being displayed 4x the size of the non-retina image instead of being scaled down. Any idea of how to…
W Dyson
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CAEmitterCell - slow stars or light effect

I'm playing around with CAEmitterCell, but most effects are very fast effects like the firework. But I want to have a slow "stars" effect like you see here on www.findyourwaytooz.com How can I do that with CAEmitterCell? Thank you :)
cuSoon2013
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CAEmitterLayer not timing correctly with CACurrentMediaTime() and sometimes not showing at all

I am currently making a particle emitter using CAEmitterLayer and ran into the issue of the layer preloading the animation when I start it and hence the particles all over the place when I show it. Many answers have said the culprit is…
Roodey
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Animating already emitted CAEmitterCell objects

I have a CAEmitterCell that I am using to emit a continuous background for my game. When the player "dies", I want the background to slow to a stop, so I did this: - (void)stopAllEmitters:(NSTimeInterval)duration { for(CAEmitterLayer* layer in…
Liftoff
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How to use CAEmitterLayer on macOS in a SwiftUI app using NSViewRepresentable

I want to use a CAEmitterLayer within a macOS app that is based on SwiftUI. Problem: The layer itself is perfectly visible, but it doesn’t emit any particles. → Here’s my demo project on GitHub I basically built a NSViewRepresentable for a custom…
ixany
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iOS (Swift) Changing a property of a CAEmitterCell after it's been initialised

My aim is to create a fire effect using a CAEmitterLayer, whose strength can be altered via changing the value of the alphaSpeed property of its given CAEmitterCells. A smaller value of the alphaSpeed would result in a "roaring" fire, whilst a…
ajrlewis
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CAEmitterCell automatically stop to emitting after sometime

CAEmitterCell emitting for 2 to 3 minutes but after it stops to emitting automatically. So my question is how can I set CAEmitterCell so that it will emitting infinite. Is there is a way to continuously emitting the CAEmitterCell or Is there any…
Jagat Dave
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CAEmitterCell without using an image?

I'm having trouble finding enough documentation on CAEmitterCell. It's contents seem to be able to set to any object, but as far as I can tell from examples online it's always been set to an UIImage. Is there any way to set anything else to the…
Vadoff
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