iphone 4 higher resolution pics vs 3gs - iphone

i just have a 3gs for testing (here in romania i still cant get a iphone 4)
When I just create full screen images for iPhone 4 .. would they be displayed resized on the 3gs?
I just cant make a bundle version for 3gs and 4 with 2 times my images, they are already a lot. Do I have to make now 2 Apps ??
Could this be a trick: In my xib i define a 320x480 UIImageView (it will be resized automaticly on the iPhone4) when I there define "scale to fill" and make high resolution images, would they come more sharp on the iPhone 4?
Now I am just wondering how to work best right now for big animations.
thx

Just found out in my case its fine to use higher resolution pics into a 320x480 frame like for 3GS and make Aspect FILL.
When I test on a iPhone 4 Simulator it shows much higher resolution and same on iPad if I click 2x :)

you can also create alternative high resolution images with a name ending in "#2x". so if you have an image called "arrow.png", create one with twice the resolution called "arrow#2x.png" and the iphone 4 will use that.
check out this article: http://thomasmaier.me/2010/06/dealing-with-iphone-4-resolution-2x-inside-of-photoshop/

Try it and find out, but my suspicion is that even if they do work, they won't work on OS 3.0 or OS 3.1, and plenty of people have not upgraded yet.
Also note that even if it displays them at half-size, I'm pretty sure that they'll still be "#2x" images. This means they'll use more memory and generally perform worse.
What's wrong with adding a handful of new images? The normal-size images are a lot smaller than the #2x images.
EDIT: If you have a lot of images, you may find it beneficial to use JPEGs where appropriate (e.g. for photos or photo-like backgrounds). I'm not sure, but I think they should work with +[UIImage imageNamed:] though you might have to specify ".jpg" explicitly.

Related

How to make app compatiable for iphone 4S and 5?

I am new to UI design, however a client wants an app ready for both iPhone 4s & 5.
I understand the iPhone 5 will create two bars if the image is not long enough. Many people said coding it at #2x will solve the problem. But I'm not sure exactly what that means.
Do I need to design two versions? What happens if I design only for iPhone 5? Will iPhone 4S users see a squished screen?
Thanks.
First, in a couple of months you'll have to support the iPhone 5's screen size. Apple have announced that it'll be a requirement soon.
Adding a Default.png of the right size is enough to enable an app to support the new screen size but is likely not enough. You'll also need to make sure that all your views resize to fill the screen. There's the old "springs and struts" method and the newer "constraints." There are tutorials you can search for -- Stackoverflow is not a good place for that kind of thing. You'll also need to update any images.
In short, try it in the Simulator and see what happens.
Using #2x is referring to whether or not the image asset is being displayed on a 'retina' screen. For example, if you had a 50x50 pixel image, the 'retina' (#2x) version would be 100x100. This is because 1pt (point) is equal to 2px (pixel) on a retina screen.
There are a variety of ways you can determine is it is an iPhone5 or iPhone4.
In the viewDidLoad, you could check the self.view.frame.size.height to determine which background image to load based on the height of the screen. This would require you to have two different versions of the assets (not including #2x versions), i.e. bg_iphone5.png & bg_iphone4.png.
There are other ways to accomplish this, and people have explained it better than I have here - search StackOverflow and you will surely find what you're looking for.
What happens if I design only for iPhone 5? Will iPhone 4S users see a squished screen?
Don't do this. Design for both.

Cocos2d/Cocos2d-x Retina Issues

I have a multiplatform iOS/Android game that I programmed in Cocos2d-x. I have only one set of images to use (I'm only after high res devices) that get scaled according to the device's resolution. For example all images are for the iPad but if you are using a Galaxy S then the image locations and scaling are affected by GalaxyS_screenWidth/iPadscreenWidth.
This works fine for all Android devices and on iPad, iPad2 and old iPhones, but with Retina iPhone there is a problem. On the iPhone 4 all my images look extremely pixelated, a result from the images being scaled to iPhone non-retina resolution then scaled back up to fill the screen.
I tried enabling Retina Mode and the images are half of their intended size (maybe due to the usage of get winsize() which uses points) and scaling manually causes other sorts of problems. I tried playing with a lot of options and attributes but to no avail, so what should I do now?
EDIT:
This is not only a graphics issue, as text gets automatically scaled down then up and appears pixelated.
EDIT 2:
Fonts are bitmaps so my bad. But I don't want to use retina as all images are already retina by default. All of my images are set up for the iPad so for iPhone 4 I just scale them down a bit. This works with Android phones.
For example I have an image, depending on screen resolution obtained through getwinsize():
If current resolution width is 1024 then image stays the same.
If current resolution width is 900 then image gets scaled by 900/1024, no problem.
If device is iPhone 4 resolution width is 480, so image gets scaled by 480/1024, then cocos2d-x automatically scales the resulting image by 2 thus the pixelation. I tried using getwinsizeinpixels, I tried multiplying the screen size, I tried many things but nothing worked out of the box unless I am to redo many of my code.
So the question is, how can I just let the damn engine treat the iPhone 4 as an Android phone with resolution of 960x640?
If you want Retina resolution images to look like Retina resolution images, then those images need to be in Retina resolution (960x480).
If you first scale down the image to 480x320 and then upscale it on the device, it will of course look blurred. You can't magically make the Retina pixels appear from a lower resolution image by scaling it up.
SI couldn't get to the bottom of it so I employed a hack. I enabled Retina Display then I scaled everything x2 through code except for the text. Sounds stupid, but it worked, and pixelation is gone. Thanks everyone who spent time trying to help me.
I tried enabling Retina Mode and the images are half of their intended size
when you enable retina support, cocos2d gets images by appending #"-hd" to their provided filenames. Such images are meant to be double the "visual" size (in iOS terms, pixels vs. points), so that they can be sort of scaled down to make full use of device resolution.
If you have a look at the CCDirectorIOS class, you will find there a couple of methods dealing with this, especially those dealing with the scalingFactor. I don't know what kind of changes you should do to make it work, but if you step into those methods and look at the value of various objects, you might find a way to modify cocos2D default behavior for your specific case.
If this seems to complicated, one thing you could try is changing the CC_RETINA_DISPLAY_FILENAME_SUFFIX so that cocos2d will not look for specially-named files for the retina iPhone, but just use the normal ones.
For example all images are for the iPad but if you are using a Galaxy S then the image locations and scaling are affected by GalaxyS_screenWidth/iPadscreenWidth.
Another thing you might try is not using winSize, but winSizeInPixels, so that when you scale down, you down do it down to the point resolution, but just to the pixel resolution (which is double the point resolution).
Hope this helps.

iOS 5 - animated gifs showing in wrong colors sometimes

I'm using some animated gifs on our mobile-site. It's a clock-animation and since the iOS 5 update it sometimes happens that the clock gets blue instead of red, as planned. Happens on iPhone4 and iPhone5 with the new os.
Any ideas what could cause the problems? It's hard to reconstruct this failure but it happens from time to time.
Any help would be appreciated.
Sometimes ios devices may not be able to process all the images because of its relatively low graphics ability compared to that of a computer. Instead of using a GIF I would suggest using an animated PNG. This has been more popular among the ios devices as using GIFs has become obsolete when working with ios devices. I am not sure how fast this would be, but I would say it can apply less stress then that of a gif. Another idea, because it is a clock gif is to analyze the gif in a program and determine any problems. Also use imgoptim (for mac) or pngcrush for windows to reduce the size of the gif to reduce the stress on the processor.
use GIF 128 Dither and Please make sure that images size has to be base on the resolution it happen some time if your images size is not depend on retina or normal resolutions. And if I am not wrong you facing problem only in retina device, may be below details will help
iPhone Retina Display
~~~~~~~~~~~~~~~~~~~~~~~
Width - 640px
Height - 960px : including 40px status bar
DPI - 326
You can use Cocos2D framework, Cocos2d and UIKIT both work great with out any graphic related errors... Sprite sheets reduces the memory usage and also support all transparant images , you can run animation ,stop and repeat them. Good luck..

upgrading code from iPhone 3 to iPhone 4

Considering that the iPhone 4 has a much higher screen resolution than iPhone 3 -
How can I port my code to iPhone 4.
Won't recompiling it change the appearance of images, controls, etc.?
The provided UI elements should take care of the scaling for you. For anything you render, you'll need to take into account the screen resolution and scale accordingly. You might want to look at :
http://developer.apple.com/library/ios/#documentation/2DDrawing/Conceptual/DrawingPrintingiOS/SupportingHiResScreens/SupportingHiResScreens.html%23//apple_ref/doc/uid/TP40010156-CH15-SW1
I'm sure you already know this, but just in case you don't: you should be sure to include larger assets in your XCode project with #2x before their file extensions. For example: icon#2x.png. #2x tells iOS to use the larger version of the asset for Retina and iPad displays.

question regarding retina display assets on older handsets running 4.x

So I'm building an app for 4.x devices and I'm wondering if I can just use one set of assets at double resolution instead of one set with a #2x id and another set without.
Basically im asking can the older 3g and 3gs just use the #2x assets? and do the right thing with them?
anyone have experience with this?
Thanks
You're better off using two sets of resources, one for the high resolution retina displays and one for the older displays. Downsizing #2x graphics won't look pretty and will impact performance, especially on 2G iPod Touches.
The older devices can use the #2x but as far as I understand you'll need to:
Set your UIImageViews to scale the images to fit.
Hardcode image references to the new images.
Expect poor image quality and slower performance on non-retina devices.
Overall, it's better to provide two copies of the images, "bob.png" and "bob#2x.png" then reference them in code as "bob.png".
NB. As of iOS4 you can reference the images without their file endings, so just "bob" would work; however this has compatibility implications with devices running pre-iOS4 : the images won't be found. So for maximum compatibility include the file endings if you intend on deploying to both iOS4 and iOS3.x.
They technically can, given you make sure they're scaling the right way (e.g. if it's an image view that it's set to scale up/down).
However it's not recommended in most situations, mainly because it'll be slower, uses more resources, and leads to shorter battery life. Also, depends on your resources but an artwork scaled down by a factor of 2 doesn't have the same quality as one that is resampled specifically for the new size.