i have passed many many days on this problem, i've not very clear in mind what convertToWorldSpace, convertToNodeSpace does...
i have 2 layer (CCNode) one that i can scale, one for panning the screen, so i scale always what is displayed makeing the center of scaling the middle of the screen:
scaleLayer=[CCNode node];
scaleLayer.position= ccp( size.width /2 , size.height/2 );
[self addChild:scaleLayer z:-2000];
panLayer=[CCNode node];
panLayer.position= ccp( -size.width /2 , -size.height/2 );
[scaleLayer addChild:panLayer z:-2000];
now i add sprites to panlayer:
[panLayer addChild:mysprite z:2];
i'd like to have a button that, when pressed, moves panlayer to make the sprite in the middle of the screen.
i have wrote this but works only if scaleLayer.scale=1
CGPoint p;
p=[panLayer convertToWorldSpace:mysprite.position];
p.x=(panLayer.position.x+(240-p.x));
p.y=(panLayer.position.y+(160-p.y));
[panLayer runAction:[CCMoveTo actionWithDuration:0.5 position:p]];
how can i make the sprite to be at center of the screen with different scales?
thanks
I'm not sure what your existing code does but you might find the property mysprite.boundingBox useful. It will give you a CGRect with the sprite's width and height and the position of its bottom left corner, and it will reflect whatever scale you have applied to the sprite.
Related
So i trying to do paint and i run into some problems. When i try to draw QGraphicsRectItem it doesnt get positioned where i want it.
QColor neki1(23, 145, 195);
QPen pen1(neki1, 2, Qt::DashLine, Qt::RoundCap, Qt::RoundJoin);
QGraphicsRectItem* sel = new QGraphicsRectItem(0,0,100,100);
sel->setPen(pen1);
sel->setBrush(Qt::transparent);
addItem(sel);
this is the code and picture and you can see it get position like somewhere in the middle of the screen. On the begining of the program i set scene->setSceneRect(QRectF(0, 0, 1000, 1000)); but cordinates in top left corner of scene are not 0,0. Is there anyway to solve this?
Thank you for your help.
Oh, that's common mistake. You had set scene's bounding rect. But QGraphcsView can scroll about and zoom into that scene.
It "aims" at top left corner of scene, so 0,0 is somewhere near middle. You have to match view to the scene's bounding rect, e.g. with setAlignment, fitInView, etc.
At the end of the game, I want to zoom out my CCLayer to show all the sprites. When I reduce the scale, the CCLayer become smaller and centered, what I want to know is how to scale the CCLayer and keep its y=0 (Origin at the bottom of the screen). Thanks in advance.
Best regards,
I believe that all CCNode children have an anchorPoint property. CCLayer defaults to (.5,.5) , midScreen. Try setting your layer's anchor point to (0.,0.).
I inherited from the QGraphicsObject and created a new class that has a pixmap and sets its transform origin point to:
setTransformOriginPoint(boundingRect().center());
But when I call setRotation() on the my class (which is added to a QGraphicsView using the scene), the rotation doesn't use the center as the rotation anchor. How can I set the center to be the anchor of the rotation ? Thanks !
More information: calling setRotation() outside of a sceneEvent function it works, but inside a sceneEvent, upon a pinch gesture, the origin point doesn't work.
Draw pixmap at QRect(0, 0, pixmap.width(), pixmap.height(). Use this rectangle for bounding rect also. Use setPos to move the item around the scene. Use setTransformOriginPoint(pixmap.width() / 2, pixmap.height() / 2) to set the origin point. These coordinates are in the item coordinates, so they should point at the pixmap's center regardless of the item's position.
Can anyone provide some basic pointers on placing CCSprites on screen?
Example:
CCSize s = CCDirector::sharedDirector()->getWinSize();
With s, say I wanted to position a sprite on the very bottom of the screen starting at 0, think something like grass.
if I am running at 1024 x 768, middle is:
setPosition( ccp(s.width/2, s.height/2) );
so starting all the way left and middle would be:
setPosition( ccp(0, s.height/2) );
So how do I get farther down?
setPosition( 0, s.height) );
This puts me starting at the top left and staying along the top of the screen.
Any help would be appreciated.
Position is relative to the sprite's parent, as well as its anchorPoint.
anchorPoint generally ranges from 0 to 1 for each coordinate, with a default of 0.5. I say "generally" because it can really be any value, but ranges outside of 0-1 place you outside of the bounds of the sprite.
For example, an anchorPoint of (0,0) makes positions relative to the bottom left. (1,0) is the bottom right, (0,1) is the top left and (1,1) is the top right. (0.5,0.5) is the very center of the sprite, which is the default.
Basically you just multiple the value by the width to get the relative position.
If you want to place a sprite at the very bottom of the screen (the bottom left corner aligned with the bottom left corner of the screen), you can do it multiple ways, based on the anchorPoint alone.
With the default anchorPoint of (0.5,0.5), the position would be (sprite.contentSize.width/2, sprite.contentSize.height/2).
If you set the anchorPoint to (0,0), the same position is obtained by simply (0,0).
If you wanted to move that sprite to the very center of the screen (the center of the sprite right in the middle), with an anchorpoint of (0.5, 0.5), the position would be (s.width/2, s.height/2).
This is all assuming you are adding a sprite to a parent the size of the screen, which is where the 2nd part of positioning comes in.
Position is also relative to the sprite's parent - which could be any other CCNode (CCLayer, another CCSprite, etc).
The way to think of that is not much different than adding a full screen node - except think in terms of the parent's size and position, not the screen.
Also Just to add something, all buttons start out in the middle of the screen then you can move them from there. if you wanted to button at (0,0):
CCLabelTTF *label1 = [CCLabelTTF labelWithString:#"Press Me!" fontName:#"Marker Felt" fontSize:20];
CCMenuItemLabel *button1 = [CCMenuItemLabel itemWithLabel:label1 block:^(id sender) { NSLog(#"button1 pressed"); }];
button1.position = ccp(-(s.width/2) , -(s.height/2)); // <---
I'm developing an ios game with cocos2d currently. There is a ccmenuitem on the screen. As the game starts, the player moves forward. In order to keep the player on the centre of the screen, the cccamera coordinates are changing according to player's position. The problem is when I click on the menuitem after the camera coordinates are changed, it does not response. For example, if the camera coordinates are moved 10 px to the right, I have to click 10px to the right of the the menuitem in order to "click on it".
Does any one know how fix this ? :(
This is a know side-effect of using CCCamera. There's rarely any need for using the camera though because you can achieve the same scrolling effect by simply moving the layer in the opposite direction.