I am developing a cocos2d game. I need to make it universal. Problem is that I want to use minimun amount of images to keep the universal binary as small as possible. Is there any possibility that I can use same images I am using for iphone, retina and iPad somehow? If yes, how can I do that? What image size and quality should it be? Any suggestion?
Thanks and Best regards
As for suggestions: provide HD resolution images for Retina devices and iPad, provide SD resolution images for non-Retina devices. Don't think about an all-in-one solution - there isn't one that's acceptable.
Don't upscale SD images to HD resolution on Retina devices or iPad. It won't look any better.
Don't downscale HD images for non-Retina devices. Your textures will still use 4x the memory on devices that have half or even a quarter of the memory available. In addition, downscaling images is bad for performance because it has to be done by the CPU on older devices. While you could downscale the image and save the downscaled texture, it adds a lot more complexity to your code and will increase the loading time.
There's not a single right answer to this question. One way to do it is to create images that are larger than you need and then scale them down. If the images don't have a lot of fine detail, that should work pretty well. As an example, this is the reason that you submit a 512x512 pixel image of your app icon along with your app to the App Store. Apple never displays the image at that size, but uses it to create a variety of smaller sizes for display in the App Store.
Another approach is to use vector images, which you can draw perfectly at any size that you need. Unfortunately, the only vector format that I can think of that's supported in iOS is PDF.
Related
Im building multiple apps in React-native and I know that there its possible to put in multiple images that have a different density. React-native selects them automatically in the tag. I know for native Android and iOS they do the same.
I get it if you want to have some changes for lower density devices. Maybe a other design of a icon or something like that. But what if you have the 3x and then resize it to a 2x and 1x. Then you have the same image but with a smaller file.
Now my question is does it really matter to add the 2x and 1x if I already have the 3x? I don't see any performance of quality issues with that.
I guess (but not sure) it can give a RAM issues with large amount of images shows simultaneously.
Plus a famous android developer says that Android has an issue with downscale big images.
I am about to launch a new app and would lik eto increase quality of the graphics. In my case the graphics is the logo and the custom buttons. I do not know if this impact Core Plot but that is also part of the package.
There is quite a few posts about this but there are still things i do not fully understand.
I am reading this quote from "amattn":
It's trivial:
1.Only include #2x images in your project.
2.Make sure those images have the #2x suffix.
The system will automatically downscale for non-retina devices.
The only exception is if you are doing manual, low level Core Graphics drawing.
You need to adjust the scale if so. 99.9% though, you don't have to worry about this.
From this post: Automatic resizing for 'non-retina' image versions
My question in regards to this is:
1. Should i do the testing on retina simulator only, as if i place a #2 grapic on
non-retina it will be too big? ...or is there an other way of doing it?
2. Should i always use a ImageView or is it OK to drag the image on the screen,
this is the logo i am talking about?
3. What about custom made buttons with images, how should i do with those?
4. What is the normal process to manage the different screen sizes, do people
add images for all displays or using this type of process?
Should i do the testing on retina simulator only, as if i place a #2 grapic on non-retina it will be too big? ...or is there an other
way of doing it?
It doesn't really matter which simulator you test on because as long as your non-retina and retina graphics are named correctly (image and image#2x) the correct image will be displayed automatically.
Should i always use a ImageView or is it OK to drag the image on the screen, this is the logo i am talking about?
When you drag and image from the project directly onto a view in interface builder you don't really see it happen but it has automatically created and image view which is containing the image your dropped in.
What about custom made buttons with images, how should i do with those?
[myButton setImage:[UIImage imageNamed:#"myFileName"]];
As shown in the above code you should always use the non-retina fle name when you reference the image a UI element should use. That was if iOS detects the device is retina it can automatically use the #2x version in its place.
What is the normal process to manage the different screen sizes, do people add images for all displays or using this type of process?
Yes, including multiple image resolutions common practice and is required for iPhone apps (not sure about iPad) to include both retina and non-retina images. But regardless of the requirements, you should definitely support both device resolutions to keep your customers happy!
I am developing an iOS application for iPad. Currently I am using images of resolution 2048×1536 px (iPad3 resolution). If I run this app on iPad2 or iPad1 will it get fitted to its resolution (1024×768 px)? Or should I use a 1024×768 images and specify image#2x for iPad3?
Since I only have iPad3 , cannot know how the images will be seen in the lower resolution devices. But it should work perfectly on them too.
Any help greatly appreciated. Please cite your sources.
You could try this in the simulator if you don't have a non-retina device.
It's certainly possible and will usually look fine (at least for photos, text and icons may look worse when scaled down), but you are wasting quite a lot of memory which is pretty scarce on an iPad 1 (it only has 256 MB), so you should usually also include non-retina images.
Automatically scaling down images typically results in visual artifacts, which is why the SDK includes an easy way to include different versions of any image, instead of just a single big one.
As far as I know, all iOS devices (within the same family) have resolutions that are multiples of each other so automatic scaling artifacts are somewhat mitigated, but it is still best to include the correct resolution.
I'm currently optimizing my iOS app for the new iPad. Unfortunately by adding launch images for the iPad retina display the size of my ipa grows from 1.2MB to 5.5MB, mainly because of the two PNG images in 1536 x 2008 (portrait) and 2048 x 1496 (landscape). The size of these images are respectivly 1.9MB and 1.7MB.
The portrait can be seen here: http://uploads.demaweb.dk/iPadPortrait.png.
As you may notice, the background is a fixed pattern but sadly it seems that this is not very compressible. I've further tried to compress the images using ImageOptim, but it does not make any difference after Xcode has compressed the images during the archive. Searching the web I've noticed, that some people are dissuading to turn off PNG compressing in Xcode.
Are there anything I can do? It is not a solution to change the pattern in the image to a solid color, as it should look like the background in my iOS view. But it seems odd, that supporting the new iPad increase the size by ~4MB.
I was able to get it down to 633KB with pngquant (64 colors with slight dithering, which is barely noticeable on regular screen, and should be absolutely invisible at Retina resolution) and ImageOptim.
Yes, you will need to disable Xcode's conversion to avoid Xcode inflating files by converting them to ARGB.
NB: the article quoted in the accepted answer provides no benchmarks at all for the claimed speed difference.
It also contains correction that it is possible to optimize images with ImageOptim for iOS apps.
I'm using a great tool called ImageOptim
It incorporates a number of tools inside which crush your png files significantly (in my case it was between 25% to 50%).
One thing to remember is to disable Xcode's PNG optimization (as explained on the website)
EDIT:
Simply drag the images to the imageOptim window and the optimization will start automatically
Ive struggled with this too, unfortunately not much can be done.
In an effort to dramatically increase drawing performance of iOS apps,
Xcode re-compresses PNG files as it builds. It premultiplies the alpha
channel and byte swaps the red, green and blue channels to be
sequenced blue, green and red. The result is optimised for iOS’s
purpose, but as a side effect, ImageOptim’s work gets undone…
Source
I'm trying to build a weather application on the iPad but it seems that I need some help in animation. Say I'm animating a Radar, so the radar source files have 10 gif/jpeg pictures in 900x700 pixel size. I've tried the UIImage animation technique using the tutorial here:
http://www.icodeblog.com/2009/07/24/iphone-programming-tutorial-animating-a-game-sprite/
but it seems that loading 10 images that big is too much for the iPad to handle and its crashing due to memory warnings. I'm researching other techniques to animate but I can't seem to find something that will do this efficiently.
I've looked at others like Core Animation using sprites, and Cocos2D with sprites. Can someone point in the right direction the best way to animate these big images? (keep in mind that these images are dynamic and changes often so the sprites will have to be recreated on a server and fetched from the iPad to do the animation). Thanks
OpenGL only creates textures with dimensions at powers of 2. In the case of your images, that's 1024x1024, which is a meg of memory per image. Still, that shouldn't be a problem with the iPad.
First, investigate using Xcode's profiling tools to ensure the images aren't being repeatedly loaded into memory at each loop of the animation (likely by way of new objects that aren't sharing cached textures). That could solve your problem from the start.
Second, I recommend using Cocos2D if only for the easy handling of textures and caching. Toss the images into a CCAnimation, pop that into a CCRepeatForever, run it with a CCSequence. When you're done hit CCTextureCache to release unused textures.
Third, lower your animation framerate to 30 or less (if only for this animation). It may be the iPad, but you making a weather app. Not a video game.
Finally, downgrade the size of your image. Justify all you want, but a large radar animation will not sell your app. And just because a website might already be playing that animation beautifully, remember that a desktop has vastly more memory and power than any smart phone.
Try breaking the animation image into into smaller parts and animate those instead by treating each components as sprites. It would be best if you use primarily code (CoreGraphics) and draw your radar "by hand" instead of just using images as if they were animated GIFs.