Why is the coordinate system in sprite kit flipped and can I change that globally?

Question

I noticed that in Sprite Kit the coordinate system is flipped.

For example, here is a SKSpriteNode:

SKSpriteNode *car = [SKSpriteNode spriteNodeWithImageNamed:@"car"];
car.position = CGPointMake(0, 0);
[road addChild:car];

The car is positioned in the center of it's parent.

When I set position to:

car.position = CGPointMake(-50, 0);

then it is positioned more to the left. But when I want to move it down, and increase Y, it moves UP!

car.position = CGPointMake(-50, 20);

In UIKit increasing Y always means something moves down. It feels more logical to me. Is there a way to flip the coordinate system in Sprite Kit?

Don't fight it, embrace it. This is the standard OpenGL coordinate system. — CodeSmile, Dec 23 '13 at 01:53

score 10 · Accepted Answer · answered Dec 22 '13 at 21:09

You can set your scene's yScale property to -1. Everything will render upside down, but you can also set the yScale property for each node to -1, which will cause them to render right side up.

You could also make a class category and create a property called invertedPosition with a custom getter/setter that inverts the default position property.

score 0 · Answer 2 · edited Sep 14 '14 at 22:02

0

Sprite Kit uses a coordinate orientation that starts from the bottom left corner of the scene (0,0), and the values increase as you move to the right (increasing x) and up (increasing y).

edited Sep 14 '14 at 22:02

Vingdoloras

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answered Mar 26 '14 at 08:49

alpennec

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This doesn't answer the question of "can I change that" – Alex May 10 '20 at 19:24

Why is the coordinate system in sprite kit flipped and can I change that globally?

2 Answers2

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