A fast, easy to use, free, and community supported 2D game engine
Clave
Member
Hello experts,
I am having an application which has made using Cocos2D. I am trying to implement a module which has to do the following item I.,
I. Picking picture from photo library and keep the picture in editing mode where user should be able to tap and drags that picture anywhere in the screen (or) user should be able to pinch or expands with two fingers anywhere on photo.
Thank you.
Clave/
Joethemonkey101
On probation
He said he wants to implement that feature, that's probably not the app
Well, it is not that difficult to implement in cocos2d.
Just grab the image from the library, create an sprite out of it and then add the touches code.
Dragging just requires you to change the sprite's position to match the location of the user's finger on CCTouchMoved
Scaling up/down would be done by tracking 2 finger's positions and on CCTouchMoved look at the distance between them, if the distance becomes greater on the next step, then scale the sprite up, if it happens the other way, scaledown.
Rotation: With 2 fingers over the sprite you should retrieve the angle formed by the line that the 2 fingers create. Then if that angle changed in the next step, rotate the sprite by the same variation of the angle.
Well I'm developing an app that needs to handle pictures. But, I'm not using cocos2d for this project. To not lose photo's original quality and to manage memory efficiently, if it is large, you will need clip it into tiles (little pieces), there is an example from Apple called TiledImageView or something...
Clave
Member
Hello Mr.pabloruiz55,
I tried that what you suggested to me. I'm being successful for picking the image from photo library and put into a Sprite. I'm facing a problem here is that, my application screens are in landscape mode, but when i launch photo library it shows in portrait mode. I don't know how to show photo library screen in landscape. If you know please guide me?
And the main problem is with pinching/zooming Sprite image. After i picked the image from photo library, i resize the image and make fit into Sprite. Now i have to implement pinching/zooming facility for this Sprite image. I'm not getting any help or info on this one, i searched a lot. Could you please give me some samples or guide me how can i resolve this?
Thank you in advance.
About the pinching to scale. You basically would do the following, sorry i don't have any code at hand but i have done this before and works fine.
1)On touch began, store 2 touches. You'd be better by having 2 instance variables to hold those 2 touches.
2) Once you have those 2 touches, on touch moved save the distance between them into another variable. (you can get it by using ccpDistance)
3) On touch moved you must get that distance you calculated on the previous step and calculate the difference between the that and the new one.
4) set the scale of the sprite according to the value calculated. So if the distance before was 10 and the actual distance is 15, you would have a difference of 5. You should multiply it by 0.01 or a value you see fit so the scaling is not so big.
5)Remember to correctly set the 2 variables you used to store the 2 touches to nil on touch ended.
Hope that helps
Clave
Member
Hi pabloruiz55, Please tell me how do i store 2 touches in TouchBegan? I tried like below, but it stores only one touch at a time.
CGPoint location; // global variable
- (BOOL)ccTouchBegan:(UITouch *)touch withEvent:(UIEvent *)event
{
NSSet *allTaps = [event allTouches];
for( UITouch *touch in allTaps)
{
location = [touch locationInView: [touch view]];
location = [[Director sharedDirector] convertCoordinate:location];
}
}I am able to do stretching image by scaling it with some animation like below:
id action1 = [ScaleTo actionWithDuration:0.5 scale:2.0]; // scaling up
[frameBG runAction: action1];Currently it is scaling image when we touch anywhere in the screen. But i want scale it only when touch happens inside the Sprite? Is it possible to do and how?
Could you help me on these?
Thank you.
You must log in to post.