Bitmap:setAnchorPoint or Sprite:setAnchorPosition

flashjaysan

What is the difference between the two methods Bitmap:setAnchorPoint or Sprite:setAnchorPosition? The former seems to offset the texture and the latter seems to offsets the origin of the sprite. What are the differences and more importantly what are the usages of those methods?
I kind of think both could be used to displace the origin of a sprite to make it rotate and scale around it but I don't see very well when to use one or the other.

oleg

Sprite:setAnchorPoint = in percent (0-1)

Sprite:setAnchorPosition = in pixels

Apollo14

I use setAnchorPoint(0.5,0.5) very often

Recently there was discussion of KnifeHit game mechanics, there is good example of using setAnchorPosition(in pixels), by @antix
http://giderosmobile.com/forum/discussion/7355/knife-hit-mechanics-how-to

flashjaysan

@2oleg you're very terse in your responses, no?
@Apollo14 Thanks for your link but it's too high level for mine. I don't understand the discussion. I'm a beginner after all.

oleg

@flashjaysan These are the consequences of using twitter

flashjaysan

@oleg Ah ah!

oleg

Guys and how to anchor only one axis?
setAnchorPointX(0.5)

Apollo14

oleg said:

Guys and how to anchor only one axis?
setAnchorPointX(0.5)

yourSprite:setAnchorPoint(0.5,0) --first value is X, second value is Y. They both =0 by default

oleg

Apollo14 said:

oleg said:

Guys and how to anchor only one axis?
setAnchorPointX(0.5)

yourSprite:setAnchorPoint(0.5,0) --first value is X, second value is Y. They both =0 by default

I need Y to not change,

Even if I have an anchor of 0 and again putting 0 - the sprite updates its position, and I don't need it! -I need the sprite - did not change position.

hgy29

oleg said:

Guys and how to anchor only one axis?
setAnchorPointX(0.5)

Generally speaking, you can't do taht with setAnchorPoint, you'll have to use getAnchorPosition followed by setAnchorPosition, leaving the axis you don't want to change at its previously read value. Of course you'll need to compute the anchor position in pixels, multiplying the ratio width the sprite's width or height.

As a particular case, you can do it with Bitmap, since it has a getAnchorPoint call.

oleg

hgy29 said:

oleg said:

Guys and how to anchor only one axis?
setAnchorPointX(0.5)

Generally speaking, you can't do taht with setAnchorPoint, you'll have to use getAnchorPosition followed by setAnchorPosition, leaving the axis you don't want to change at its previously read value. Of course you'll need to compute the anchor position in pixels, multiplying the ratio width the sprite's width or height.

As a particular case, you can do it with Bitmap, since it has a getAnchorPoint call.

I do exactly that, but I thought maybe there was another solution ..

Apollo14

it could be convenient if we could pass negative values

setAnchorPoint(-0.5,0)

oleg

Apollo14 said:

it could be convenient if we could pass negative values

setAnchorPoint(-0.5,0)

Just the anchor will be outside the sprite on the left

oleg

I created my own function that correctly sets the anchor:

function setAnchorPointX(sprite,x) --встановити якір тільки по одній осі local x2,y=sprite:getAnchorPosition() y=y/sprite:getHeight() sprite:setAnchorPoint(x,y) end