UIImageView interactions - iphone

I am working on an app in which I want similar kind of functionality as that of WebMD body image.
How can I identify which part of image is touched in an optimal way? Do I have to slice the image according to requirements?
How can I add some tags into the image? Similar to the facebook photo upload functionality in iphone.

You need some way to figure out what the user touched, or tried to touch.
You might use a list of annotation-like objects, where each object has a location. When the user touches the image, you'll need to find the annotation in the list that's closest to the touch location and react appropriately. The "optimal" way to do that is probably to use a quad tree. For an iPhone app, though, the number of touchable points is probably pretty small (several dozen?), and a brute force search through the list will probably be more than fast enough.
Another option would be to overlay a transparent view on top of your image for each region that you want the user to be able to touch. Doing this would also make it simple to draw a "tag" at each of those locations.

Related

iPhone iOS how to create interactive drag, rotate, resize, delete view control?

I got an app that allows users to add content to a canvas. I would like to be able to offer the user an ability to move, rotate, resize, reflect this content. Currently I'm doing this with gestures, but would like to know if there is some sort of open-source widget that draws a box around the view and adds 4 buttons to do these functions:
rotate 90 degrees
rotate freely
resize
delete
Can anyone think of an open source framework that I can add to my project to create controls like the ones displayed?
I can probably build this by hand, but debugging gesture recognizers and view rotation is not the most fun thing, so I'm looking for something more polished.
Thank you!
Here's a link to an open source control on cocoa controls that looks like something you could use: TDResizerView.
"TDResizerView is used to resize and rotate an imageview with single finger"
Sounds like a good place to start from, even if you need to modify it.
I've never used this particular control though, so take my word for what it's worth.
edit: Also keep in mind that on iOS, users generally expect gestures. Forcing them to use the handles instead of pinching or rotating may be bad for your user experience, depending on why you want the handles instead.

Dragging/Resizing a UIImage on the Device

I'd like to allow a user to add a shape (which would just be a UIImage) onto some sort of canvas, then move and resize it on the screen but I'm not sure how to go about this. Ideally I'd like the basics of a drawing app which can use images from a user's device. Each shape would have an associated position, size and z-index.
The only thing I'm unsure of is how I'd create a bounding box (the one with four blue dots to allow resizing/moving). I have experience with UIKit, and would prefer to keep the majority of the app in this for the time being, but I get the feeling this type of thing might be better suited to Cocos2D or a similar framework.
If anyone has any pointers/open source code I can dig through it would be hugely appreciated.
I think you should look into CALayer, or even CAShapeLayer. I'm just starting to play with them, but I'm pretty sure you can easily get the functionality you want with either. Draw the border in the layer's drawLayer:inContext:. Check out the Quartz2d Guide path drawing section for the functions you need.

How to display photos like iphone homescreen?

I'm trying to make an app that's displaying my photos from camera roll like app icons in iphone (matrix view) . The pictures will have the "wobble" effect and the pictures need to be rearrangeable(the posibility to swap pictures).
I found out how to implement the wobble efect.
What`s the best way to implement the displaying and swapping functionality?
I suggest you to show your photos using CALayer.
Add those layer in Matrix like pattern in your UIView using frame property of layer.
To move or rearrange photos find particular CALayer in touchesBegin method of View using touch points and Move it with movement in touched(in touchesMoved). Settle it in a proper location in touchesEnded method.
I have assumed that you have basic knowledge of usage of classes that I mentioned in above description.
Post here if you need more help.

How to draw an image according to the pixels of another image?

HI all ,what i want is to map the images.Suppose i have two images of persons,one is of fat person and another is of weak person,Now i want to match their faces ,eyes.I want to increase or decrease the face size eye size of one image according to another.As you can see in adobe photoshop you can make the face fat,make it squueze.I want to do the image manuplation in this.These types of operations i want to implement.I don't know from where to start.
Pleas guide and help me.Can i perform all this with core graphics if so then how
Any reference,tutorial address ,sample code ........appreciated.
You are probably going to have to deal with some sort of edge detection and face recognition algorithms, at the very least, if this is to be accomplished automatically. Otherwise, if the user is going to be resizing one image to match the other, this will require simple resizing operations driven by perhaps user pinch & gestures.
UPDATE:
For manual resizing:
Download the source code for the great book Cool iPhone Projects. One of the projects is called 'Touching'. This project contains code that accomplishes what you need: pinch and zoom functionality.

Multi changeable areas of a image on a iPhone

I have an image with picture of a person and I want to let the user to pick some area of the person and change the color. But how can I best create a multi-mask image?
E.g. should the user be able the change the color for a leg or a hand.
I am using Titanium Appcelerator, and right now I had a solution with buttons placed over the image, which is not a pretty and accepted solution.
The Kitchensink example, has only one area which can be changed.
The only solution I found for working with sections of an image is to divide the image into different views then use a vertical or horizontal view to glue them together. Sounds like you took a similar approach using buttons.
Another option might be to use one of the jQuery image libraries within the webview. This most likely will have a performance penalty though.