How to create progress bar in sprite kit?

Question

I want to create my own progress bar in Sprite Kit.
I figured I will need to images - one fully empty progress bar and filled progress bar.
I have those images, I pu

Answer 1

Assuming HealthBarNode is a subclass of SKSpriteNode with a public property health that varies between 0.0 and 1.0 and whose parental property texture is generated from the entire color bar image of width _textureWidth (a private property), you could do something like this:

- (void)setHealth:(CGFloat)fraction
{
    self.health = MIN(MAX(0.0, fraction), 1.0); // clamp health between 0.0 and 1.0
    SKTexture *textureFrac = [SKTexture textureWithRect:CGRectMake(0, 0, fraction, 1.0) inTexture:self.texture]; 
// check docs to understand why you can pass in self.texture as the last parameter every time

    self.size = CGSizeMake(fraction * _textureWidth, self.size.height);
    self.texture = textureFrac;
}

Setting the health to a new value will cause the health bar (added as a child to the main scene, say) to get cropped properly.