I created a SKView which presents an SKScene subclass like this:
SKView *skv = [[SKView alloc] initWithFrame:self.view.bounds];
[self.view addSubview:skv];
self.skScene = [[TestScene alloc] initWithSize:v.bounds.size];
[skv presentScene:_skScene];
Then to see coordinate system origin, I add a small 10x10 colored square to the scene.
SKSpriteNode *ori = [SKSpriteNode spriteNodeWithColor:[UIColor greenColor] size:CGSizeMake(10,10)];
[self addChild:ori];
You can see green square in lower left corner:
From what I thought, SpriteKit coordinate system is such that origin is always in center. But in the scene the origin is in lower left corner. When I add a child node to {0,0} it appears in lower left corner as well.
When I add a SKSpriteNode and position it {0,0} in the scene, it appears in lower left corner. But it is centered around scene origin in lower left corner (clipped off half to left, and half to bottom).
But now it gets more confusing. When I add a SKSpriteNode to another SKSpriteNode, the sub-sprite is CENTERED in the parent.
So does it mean the Scene coordinate system works different than the sprite coordinate system?
Recap:
- When I position a sprite in scene at {0,0}, it appears in bottom left, clipped off 50% (centered around origin).
- When I position a sprite in a sprite at {0,0}, it appears centered in the sprite.
Is my Scene configured wrong or is this the way it works?