I’ve been developing an iOS app using Swift 4 but recently (today) decided to switch to Flutter/dart after hearing about its capabilities.
In my iOS app, I have a moving background of waves (actual waves when you think of an ocean).
The width of the the wave .png is 1606 units and I animated it in a way where it will translate from right to left 265 units in 1 second, then it repeats itself. This way, the waves are moving continuously when in reality, it’s only a fraction of the entire png repeating itself.
I needed this same background to apply to all ViewControllers (screens) in the app and I did this by sending the last known x value right before the transition through a segue (transition between viewcontrollers, I believe it’s a “route” for dart?) and used this value as the initial position of the waves in the next ViewController. When I swipe up or down, to move to different view controllers, the waves would also move accordingly.
For some reason, the animations were a bit choppy but I’d say 80% of the time, it was perfectly smooth. I need it to be 100% for when I release my app tho.
How would I go about accomplishing this type of animation in Dart?
For animations, Flare seems very promising and I’m kind of steering towards using that to accomplish my goal but I’d like to hear any advice on how I should approach this.
The animation performance depends on how it's implemented. Without a minimal repro, it'll be challenging to figure out the issue. Though other options that you may consider to animate the background is by using AnimatedPositioned widget. Using this should help manipulate the position of widgets displayed on screen.
Another one is by using Adobe After Effects animations and rendering it with lottie plugin on your app.
Related
I have programmed an Ipad application that has a behaviour that I would like to change if I put it in a wooden frame (any other material could be added). To simplify things, the background should change whenever is inside this frame, and there must be no tap-touch interaction, just putting the Ipad inside the frame.
Of course, we could program am specific gesture on the screen, like double tapping or swiping but it is not the searched solution.
Another thought has been to detect the lack of movement for a certain amount of time, but that would not assure that iPad is inside the frame.
I have thought about interacting with magnets (thinking about smartcovers) and the sleep sensor in the right side of the Ipad, but I don't know how to do it.
I cannot see any other useful sensor.
Any suggestion?
A combination of accelerometer and the camera seems like an idea worth trying out:
Scan the accelerometer data to detect a spike followed by a flat line (= putting the iPad into the frame, then resting).
After detecting the motion event, use the back camera (maybe combined with the flash) to detect a pattern image fixed inside of the frame for this purpose. It might be necessary to put the pattern into a little hole to create at least a blurry image.
The second step is there to distinguish the frame from any other surface the iPad might be placed upon.
I'm developing a app that will showcase products. One of the features of this app is that you will be able to "rotate" the product, using your finger/Pan-Gesture.
I was thinking in implementing this by taking photos of the product from different angles so when you "drag" the image, all I would have to do is switch the image according. If you drag a little, i switch only 1 image... if you drag a lot, i will switch them in cadence making it look like a movie... but i have a concerns and a probable solution:
Is this "performatic"? Since its a art/museum product showcase, the photos will be quite large in size/definition, and loading/switching when "dragged a lot" might be a problem because it would cause "flickering"... And the solution would be: instead of loading pic-by-pic i would put them all inside one massive sheet, and work through them as if they were a sprite...
Is that a good ideia? Or should I stick with the pic-by-pic rotation?
Edit 1: There`s a complicator: the user will be able to zoom in/out and to rotate the product in any axis (X, Y and Z)...
My personal opinion, I don't think this will work the way you hope or the performance and/or aesthetics will not be what you want.
1) Taking individuals shots that you then try to keyframe to based on touch events won't work well because you will have inevitable inconsistencies in 'framing' the shots such that the playback won't be smooth
2) The best way to do this, I suspect, will be to shoot it with video and shoot it with some sort of rig that allows you to keep the camera fixed while rotating the object
3) I'm pretty sure this is how most 'professional' grade product carousel type presentations work
4) Even then you will have more image frames than you need -- not sure whether you plan to embed the images files in app or download on demand -- but that is also a consideration in terms of how much downsampling you'll need to do to reduce frames/file size
Suggestion
Look at shooting these as video (somewhat like described above) and downsampling and removing excess frames using a video editor. Then you could use AVFoundation for playback and use your gestures to 'scrub' into the video frames. I worked on something like this for HTML playback at a large company and I can assure you it was done with video.
Alternatively, if video won't work for you. Your sprite sheet solution might work (consider using SpriteKit). But then keep in mind what I said about trying to keyframe one off camera shots together -- it just won't work well. Maybe a compromise would be to shoot static images but do so by fixing the camera and rotating the objects at very specific increments. That could work as well I suppose but you will need to be very careful about light and other atmospehrics. It doesn't take much variation at all to be detectable to the human eye causing the whole presentation to seem strange. Good luck.
A coder from my company did something like this before using 360 images of an object and it worked just great but it didn't have zoom. Maybe you could add zoom by adding a pinch gesture recognizer and placing the image view into a scroll view to zoom in on the static image.
This scenario sounds like what you really need is a simple 3D model loader library or write it in OpenGL yourself. But this pan and zoom behavior is really basic when you make that jump to 3D so it should be easy to find lots of examples.
All depends on your situation and time constraints :)
I am confused as to how endless runner games actually work, conceptually, as far as having a never-ending canvas. Sprite Kit is under NDA, so I am going to use Cocos2D as my framework.
There are some tutorials on the web that are specific to other languages, and tools, but I just need to figure out basically: If I create a scene with a specific size, how do I create the illusion of a never-ending background? Do I just animated backgrounds behind the scene, or do I somehow dynamically add length to the scene, so my runner really is running along the canvas?
Do I make sense? I just cannot grasp what the actual method these games use is. They certainly feel like the runner sprite is moving along a canvas, but maybe it's just that he's staying still and all the elements are moving?
One way that you can make the "endless" environment is by making UIViews (or NSViews depending on what platforms your game will be available on) that contain only a section of the environment so they can be reused when the runner passes that part of the game. Each view can be dedicated to display a certain feature of the game such as a power-up or an obstacle and it will be up to the logic of your game to decide when to use each view.
Lets think of endless runner like jetpack joyride.
You might want to have two background nodes, each larger than the screen size by some amount (maybe 1.5 or 2 screen widths).
When you load your level, you load first background and add second background at the coordinates where first ends, so that they form long screen. Then when we start moving character along this background when first background leaves screen we can take it, and change its coordinates to those where second background frame ends. This way when this comes to an end, we do the same with it.
This way only using 2 long images we can simulate essentially endless space.
You can use longer sequences for your game.
You can add other nodes to your background when it has left the screen and present it, so it looks different each time.
I would like to have some text appear and disappear in a puff of smoke effect in an iPhone game. For example, when someone scores points, I want to show the new points that were added. It should appear in a puff of smoke and disappear within a second or two.
How do I create that?
Have a look at Particle Designer from 71 Squared. It costs about $7.99 and includes easy code generation and integration. There are some pre-configured smoke effects available in the shared library.
http://particledesigner.71squared.com
You will most likely have kind of "cheap" effects using particles, but you'll have a good control over the animation (velocity, scaling, acceleration...).
Another way to go is to use multiple images of smoke and overlay them, then launch an UIView animation with random properties for rotating, scaling and timing.
I'm developing a game in as3 for iPhone, and I've gotten it running reasonably well (consistanty 24fps on iPhone 3G), but I've noticed that when the "character" goes partly off the screen, the frame rate drops to 10-12fps. Does anyone know why this is and what I can do to remedy it?
Update - Been through the code pretty thoroughly, even made a new project just to test animations. Started a image offscreen and moved it across the screen and back off. Any time the image is offscreen, even partially, the frame rates are terrible. Once the image is fully on the screen, things pick back up to a solid 24fps. I'm using cacheAsBitmap, I've tried masking the stage, I've tried placing the image in a movieclip and using scrollRect. I would keep objects from going off the screen, except that the nature of the game I'm working on has objects dropping from the top down (yes, I'm using object pooling. No, I'm not scaling anything. Striclt x,y translations). And yes, I realize that Obj-C is probably the best answer, but I'd really like to avoid that if I can. AS3 is so much nicer to write in
Try and take a look at the 'blitmasking' technique: http://www.greensock.com/blitmask
From Doyle himself:
A BlitMask is basically a rectangular Sprite that acts as a high-performance mask for a DisplayObject by caching a bitmap version of it and blitting only the pixels that should be visible at any given time, although its bitmapMode can be turned off to restore interactivity in the DisplayObject whenever you want. When scrolling very large images or text blocks, BlitMask can greatly improve performance, especially on mobile devices that have weaker processorst