I have an SKSpriteNode that has a texture assigned like this:
node.texture = SKTexture(imageNamed: "Oval")
Users can select this object and drag it around. I use the following to identify when it is being selected in the touchesMoved function.
var touchedNode = allObjects.nodeAtPoint(location)
The problem is that almost half the surface area of this image file is transparent. However, nodeAtPoint responds to touches on the transparency.
Does anyone know of a way to ignore the transparency?
In your touches Moved you can get the color of the pixel of the node you touched and then using an if statement you can ignore the node if the color is transparent (has an alpha of 0). Check here to see how to get the color
SpriteKit: How can I get the pixel color from a point in SKSpriteNode?
Related
How can I have a white background and use SKEmitterNode in SpriteKit?
The emitter disappears if I set the background color of the SKScene. On the default black background I can see the red particles (when I comment out "backgroundColor = .white" in my SKScene). If I use a CAEmitterLayer then I can see the particles with a white background, but would like to use SKEmitterNode. I've spent a couple hours trying to find any reference to this problem.
Code is very simple -- adds child to SKScene
if let particles = SKEmitterNode(fileNamed: "Sparks.sks") {
particles.position = position
scene.addChild(particles)
}
instead of the default .white, you may want to try setting the color with a color close to white... i.e. a UIColor where the RGB is .9,.9,.9
A little bit stuck on how to paint/draw an effect like an alpha Chanel onto an SKSpriteNode node i've started off with setting up the two images I need (ps if there is another way to do this is sprite-kit id love to know how to paint the masks
1)The hidden picture - SKSpriteNode *hiddenimageNode
2)The overlay that gets scratched away SKSpriteNode *myOverlay
3)And finally a mask node comprising of
UIImage *image;
SKTexture *maskTexture= [SKTexture textureWithImage:image];
maskNode = [SKSpriteNode spriteNodeWithTexture:maskTexture];
all of these are placed inside of a node "cropNode" [SKCropNode node];
this works more like a static image (that of a circle moving at touch location and not quite what I'm after, I'm hoping to be able to scratch away the entire image)
this works fine but its Not quite the look I'm after
Pictures: Dragging finger from pos1 to pos02, while "erasing purple layer to reveal a smileyface"
is there a way to make it look like I'm erasing the sprite?
nubie coder
//Updating project...
So since then I have tried using this code
https://github.com/oyiptong/CGScratch
and have added it to my SkScene by creating a subview then placing the UIView (Scratchview into it)the erasing is working however the erasing is not happening where the touches are occurring, any ideas why this might be happening?
If you are doing this in iOS 8, then your best bet is to just use SKSpriteNodes as your masking nodes, there is a weird bug with other kinds of nodes that causes distortion.
If you are doing this with iOS9 +, then SKShapeNodes are fixed.
I am going to explain the concept for iOS 9. To get this to work in iOS 8 is a real pain, since subtraction does not subtract alpha in iOS 8.
Now for your mask nodes, you only have 2 options for drawing, On and Off based on the alpha level of the pixels in your mask image. So what you want to do is incorporate subtraction alpha blending to create your desired effect.
let bigcircle = SKShapeNode(circleOfRadius: 80)
bigcircle = .whiteColor()
let littlecircle = SKShapeNode(circleOfRadius: 40)
littlecircle.position = CGPoint(x: 10, y: 10)
littlecircle.fillColor = .whiteColor()
littlecircle.blendMode = .Subtract
bigcircle.addChild(littlecircle)
maskNode = bigcircle
What this code is doing is making a big white circle with a radius of 80 points, and drawing a white circle inside of it at 40 points. Since we are using subtraction blending, it is going to take the new color and subtract it from the old (in our case white(1,1,1,1) - white(1,1,1,10 = transparent(0,0,0,0)) and get us a nice hole in our mask that will end up being cropped out of the layer over your smiley face.
Actually, I'm migrating a game from another platform, and I need to generate a sprite with two images.
The first image will be something like the form, a pattern or stamp, and the second is only a rectangle that sets color to the first. If the color was plane, it will be easy, I could use sprite.color and sprite.colorBlendFactor to play with it, but there are levels where the second image is a rectangle with two colors (red and green, for example).
Is there any way to implement these with Sprite Kit?
I mean, something like using Core image filter, and CIBlendWithAlphaMask, but only with Image and Mask image. (https://developer.apple.com/library/ios/documentation/graphicsimaging/Reference/CoreImageFilterReference/Reference/reference.html#//apple_ref/doc/uid/TP40004346) -> CIBlendWithAlphaMask.
Thanks.
Look into the SKCropNode class (documentation here) - it allows you to set a mask for an image underneath it.
In short, you would create two SKSpriteNodes - one with your stamp, the other with your coloured rectangle. Then:
SKCropNode *myCropNode = [SKCropNode node];
[myCropNode addChild:colouredRectangle]; // the colour to be rendered by the form/pattern
myCropNode.maskNode = stampNode; // the pattern sprite node
[self addChild:myCropNode];
Note that the results will probably be more similar to CIBlendWithMask rather than CIBlendWithAlphaMask, since the crop node will mask out any pixels below 5% transparency and render all pixels above this level, so the edges will be jagged rather than smoothly faded. Just don't use any semi-transparent areas in your mask and you'll be fine.
I have an empty SKScene which needs to be horizontally centered, so I set it's anchorPoint:
self.anchorPoint = CGPoint(0.5f, 0);
I also need to scale it, per SpriteKit - Set Scale and Physics, so I run an action on it like this:
[self runAction:[SKAction scaleTo:0.5f duration:0.0f]];
My problem is that when I detect touches, I get locations that seem strangely off.
I detect touches using the usual (locationInNode:self) method, and I'm currently adding a little blue square where the touches are, but when I touch the 4 corners of my device, I see a frame that is a quarter of my screen (correctly) but is moved to the left by a seemingly arbitrary amount
Here are some things I've already checked:
scene is initialized in viewWillLayoutSubviews, I know it has the correct initial dimensions
scene's scaleMode is set to SKSceneScaleModeAspectFill, but I've tried all of them to no avail
I was struggling with the same issue for awhile, but I think I finally got it figured out. You're not supposed to scale the scene (like it hints if you try setScale). You're supposed to resize it.
Try this:
myScene.scaleMode = SKSceneScaleModeAspectFill;
And then while zooming:
myScene.size = CGSizeMake(newX, newY);
Set Anchor Point as
self.anchorPoint = CGPoint(0.5f, 0);
And set Scene Scale Mode as ASPECT FIT, not aspect fill.
SKSceneScaleModeAspectFit
Dear all,
I have an application that uses cocos2d spacemanager with gravity set to a specific value.
If i want to make a shape in the middle of the screen it will fall down to the floor, if i set the gravity to zero all other object will not move as supposed, if i use a second spacemanager and set its gravity to 0 i cant detect collision between objects from different spacemanagers. how can i add a shape that wont fall down in the middle of the screen and detect its collision while other objects behave correctly according to the gravity set.
Also a question is, should i use shapes (Circle, rectangle, ... etc) with spacemanager and if i want to use a ccsprite (image) i should put it in a shape or i can use the sprite alone (e.g. a tree is not a rectangle or circle collision and reflection wont be natural how can i do this).
regards
Every shape has a property called mass. If you want a shape to be static and respond to collisions just set mass to STATIC_MASS like this:
cpShape *ball = [smgr addCircleAt:cpv(440,70) mass:STATIC_MASS radius:10];
to ad an image, do that:
cpShape *ball = [smgr addCircleAt:cpv(440, 70) mass:STATIC_MASS radius:10];
[super initWithShape:playerShape file:#"ball.png"];
If this doesn't work, set up a cpCCSprite in it with a shape.
You can search for cpCCSprite on google, im sure you'l find something :)