Hi,
In Corona SDK, we specify x and y coordinate to show an object on screen. We can access x and y coordinate of an object by using object.x and object.y, it will return starting x and y of that object.
Is there any method which can show ending x and y position of an object in Corona SDK. [import]uid: 176766 topic_id: 33081 reply_id: 333081[/import]
Hi robustur3,
What do you mean by the “ending” x,y position? Do you mean, say, the x,y position after the object moves (due to, say, a transition.to)? Do you mean the lower right corner of the object? Or something else?
Hi Andrew,
Thanks for your response.
When we display an object screen. For example, display.newImage(“crateA.png”,80,150) will be displayed on (80,150) position. These values are the initial values of x and y coordinate, where the image will start displaying. I need the ending position of the image in the form of x and y coordinate.
[import]uid: 176766 topic_id: 33081 reply_id: 131372[/import]
OK, it sounds like by “ending” you mean the lower right corner of the object. In that case, try the following:
[blockcode]
local crate = display.newImage(“crateA.png”,80,150)
– Get upper left corner
local ulx, uly = crate.x - display.contentWidth/2, crate.y - display.contentWidth/2
– Get lower right corner
local lrx, lry = crate.x + display.contentWidth/2, crate.y + display.contentWidth/2
[/blockcode]
Since crate.x and crate.y represent the center of the object, subtracting or subtracting half of the width and height will get you the coordinates of the corners.
Hope this helps.
Many Corona display objects when you pass the X, Y as parameters, it assumes you want those to be the Top Left of the position, temporarily setting the reference point to display.TopLeftReferencePoint, after that accessing X and Y should give you the center reference point.
If you do:
obj = display.newImage(“image.png”)
obj.x = 80
obj.y = 150
Then the X and Y will be the center of the image. aukStudio’s code will give you the right coordinates for the top,left and bottom,right of the image. Personally I don’t like using passed parameters to position objects because I’m never sure when they are Center or TopLeft reference pointed. I always explicitly set the X and Y like I did above to make sure I’m setting the center (or I explicitly set a reference point).
[import]uid: 19626 topic_id: 33081 reply_id: 131382[/import]
Hi robustur3,
What do you mean by the “ending” x,y position? Do you mean, say, the x,y position after the object moves (due to, say, a transition.to)? Do you mean the lower right corner of the object? Or something else?
Hi Andrew,
Thanks for your response.
When we display an object screen. For example, display.newImage(“crateA.png”,80,150) will be displayed on (80,150) position. These values are the initial values of x and y coordinate, where the image will start displaying. I need the ending position of the image in the form of x and y coordinate.
[import]uid: 176766 topic_id: 33081 reply_id: 131372[/import]
OK, it sounds like by “ending” you mean the lower right corner of the object. In that case, try the following:
[blockcode]
local crate = display.newImage(“crateA.png”,80,150)
– Get upper left corner
local ulx, uly = crate.x - display.contentWidth/2, crate.y - display.contentWidth/2
– Get lower right corner
local lrx, lry = crate.x + display.contentWidth/2, crate.y + display.contentWidth/2
[/blockcode]
Since crate.x and crate.y represent the center of the object, subtracting or subtracting half of the width and height will get you the coordinates of the corners.
Hope this helps.
Many Corona display objects when you pass the X, Y as parameters, it assumes you want those to be the Top Left of the position, temporarily setting the reference point to display.TopLeftReferencePoint, after that accessing X and Y should give you the center reference point.
If you do:
obj = display.newImage(“image.png”)
obj.x = 80
obj.y = 150
Then the X and Y will be the center of the image. aukStudio’s code will give you the right coordinates for the top,left and bottom,right of the image. Personally I don’t like using passed parameters to position objects because I’m never sure when they are Center or TopLeft reference pointed. I always explicitly set the X and Y like I did above to make sure I’m setting the center (or I explicitly set a reference point).
[import]uid: 19626 topic_id: 33081 reply_id: 131382[/import]