Animate masked image in SpriteKit (SKCropNode)

animationios7skcropnodesprite-kit

I'm using Sprite Kit to create my first iOS app, and I'm stumbling over what seems to be a pretty basic problem.

I'm trying to animate the contents (fillNode) of a SKCropNode (cropNode). The code below sets up the SKScene just fine (I see the illustration masked correctly, placed over the background image in the right location)…

SKSpriteNode *logoBG = [[SKSpriteNode alloc] initWithImageNamed:logoBackground];
logoBG.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame));
[self addChild:logoBG];

SKCropNode *cropNode = [[SKCropNode alloc] init];
cropNode.maskNode = [[SKSpriteNode alloc] initWithImageNamed:logoMask];
SKSpriteNode *fillNode = [[SKSpriteNode alloc] initWithImageNamed:logoImage];

[cropNode addChild:fillNode];
fillNode.position = CGPointMake(0,300);
cropNode.position = CGPointMake(CGRectGetMidX(self.frame), CGRectGetMidY(self.frame));
self.logoContent = cropNode;
[self addChild:self.logoContent];

…but I can't access the masked illustration to animate its position (I want it to start off outside the mask and slide into position):

CGRect screenBound = [[UIScreen mainScreen] bounds];
CGSize screenSize = screenBound.size;

SKAction *moveUp = [SKAction moveByX: 0 y: 100 duration: 5];
SKAction *moveSequence = [SKAction sequence:@[moveUp]];
[self.logoContent.target_illustration runAction: moveSequence completion:^{ // '.target_illustration' = the SKSpriteNode that I want to animate; cropNode.fillNode
    SKScene *titleScreen  = [[TitleScreen alloc] initWithSize:self.size];
    SKTransition *fade = [SKTransition fadeWithDuration:(1)];
    [self.view presentScene:titleScreen transition:fade];
}];

I can only animate the whole logoContent rather than its child nodes.

Any ideas where I'm going wrong?

Best Answer

Just for reference if anyone wants to know how to mask, here is a simple snippet

- (void) cropNodes
{
    // the parent node i will add to screen
    SKSpriteNode *picFrame = [SKSpriteNode spriteNodeWithColor:[SKColor greenColor] size:CGSizeMake(100, 100)];
    picFrame.position = CGPointMake(200, 200);

    // the part I want to run action on
    SKSpriteNode *pic = [SKSpriteNode spriteNodeWithImageNamed:@"Spaceship"];
    pic.name = @"PictureNode";

    SKSpriteNode *mask = [SKSpriteNode spriteNodeWithColor:[SKColor blackColor] size:CGSizeMake(80, 50)];

    SKCropNode *cropNode = [SKCropNode node];
    [cropNode addChild:pic];
    [cropNode setMaskNode:mask];
    [picFrame addChild:cropNode];
    [self addChild:picFrame];

    // run action in this scope
        //[pic runAction:[SKAction moveBy:CGVectorMake(30, 30) duration:10]];

    // outside scope - pass its parent
   [self moveTheThing:cropNode];
}

- (void) moveTheThing:(SKNode *) theParent
{
    // the child i want to move
    SKSpriteNode *moveThisThing = (SKSpriteNode *)[theParent   childNodeWithName:@"PictureNode"];
    [moveThisThing runAction:[SKAction moveBy:CGVectorMake(30, 30) duration:10]];
}

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You can use new Property Animation Api for color animation:

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For backward compatibility with Android 2.x use Nine Old Androids library from Jake Wharton.

The getColor method was deprecated in Android M, so you have two choices:

If you use the support library, you need to replace the getColor calls with:
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Best Answer

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