skellt

skellt

Apple Game Frameworks and Technologies: SKEffectNode not centered (p 149, B3)

On page 149 (of Beta 3) is this code to add a glow effect to the gloop droplets:

// Add glow effect
let effectNode = SKEffectNode()
effectNode.shouldRasterize = true
addChild(effectNode) 
effectNode.addChild(SKSpriteNode(texture: texture)) 
effectNode.filter = CIFilter(name: "CIGaussianBlur", parameters: ["inputRadius":40.0])

When run this shows a circular glow effect centered at the very top of the droplet where the drop number label is. The glow proceeds down about half of the drop and doesn’t provide any glow around the fattest part of the droplet. Much of glow is radiating out around the number label.

It does not look like the photo on page 149 which shows the glow surrounding the whole drop.

The cause is that the drop is a collectible which has the anchor point set to the middle top. The effect node was not given a position and is therefore centered on the anchor point by default.

To fix it in my code I added:

        effectNode.position = CGPoint(x: 0, y: -(frame.height / 2.0))

to position to effectNode halfway down the droplet in the true center.

I tried running the sample project in the end folder and it has the same bug with the glow not being centered the same way as the photo in the book.

Marked As Solved

Paradox927

Paradox927

Author and Editor at PragProg

Hi, David.

The image on that page was done in post since it was very difficult to capture a screenshot of a falling drop with any level of success.

Regarding the effect node’s position: I prefer to have the glow closer to the top of the drop to help the number stand out, which is why I didn’t adjust its position; but, yes, moving the effect node’s position—as you did—will more closely match the image in the book.

I may end up recreating that image, if possible. And I’ve updated the text to read:

Build and run the project, and you’ll see a faint glow around the top of each drop.

You’ll see this update in the next release. Thanks for letting me know.

EDIT: Good news! I was able to adjust the image. Thank goodness for source files and layers! :smile:

Where Next?

Popular Pragmatic Bookshelf topics Top

jamis
The following is cross-posted from the original Ray Tracer Challenge forum, from a post by garfieldnate. I’m cross-posting it so that the...
New
sdmoralesma
Title: Web Development with Clojure, Third Edition - migrations/create not working: p159 When I execute the command: user=> (create-...
New
herminiotorres
Hi @Margaret , On page VII the book tells us the example and snippets will be all using Elixir version 1.11 But on page 3 almost the en...
New
raul
Hi Travis! Thank you for the cool book! :slight_smile: I made a list of issues and thought I could post them chapter by chapter. I’m rev...
New
patoncrispy
I’m new to Rust and am using this book to learn more as well as to feed my interest in game dev. I’ve just finished the flappy dragon exa...
New
jgchristopher
“The ProductLive.Index template calls a helper function, live_component/3, that in turn calls on the modal component. ” Excerpt From: Br...
New
jskubick
I found an issue in Chapter 7 regarding android:backgroundTint vs app:backgroundTint. How to replicate: load chapter-7 from zipfile i...
New
brunogirin
When I run the coverage example to report on missing lines, I get: pytest --cov=cards --report=term-missing ch7 ERROR: usage: pytest [op...
New
Charles
In general, the book isn’t yet updated for Phoenix version 1.6. On page 18 of the book, the authors indicate that an auto generated of ro...
New
SlowburnAZ
Getting an error when installing the dependencies at the start of this chapter: could not compile dependency :exla, "mix compile" failed...
New

Other popular topics Top

AstonJ
What chair do you have while working… and why? Is there a ‘best’ type of chair or working position for developers?
New
ohm
Which, if any, games do you play? On what platform? I just bought (and completed) Minecraft Dungeons for my Nintendo Switch. Other than ...
New
wolf4earth
@AstonJ prompted me to open this topic after I mentioned in the lockdown thread how I started to do a lot more for my fitness. https://f...
New
dasdom
No chair. I have a standing desk. This post was split into a dedicated thread from our thread about chairs :slight_smile:
New
AstonJ
I have seen the keycaps I want - they are due for a group-buy this week but won’t be delivered until October next year!!! :rofl: The Ser...
New
AstonJ
If you are experiencing Rails console using 100% CPU on your dev machine, then updating your development and test gems might fix the issu...
New
foxtrottwist
A few weeks ago I started using Warp a terminal written in rust. Though in it’s current state of development there are a few caveats (tab...
New
AstonJ
We’ve talked about his book briefly here but it is quickly becoming obsolete - so he’s decided to create a series of 7 podcasts, the firs...
New
PragmaticBookshelf
Author Spotlight Mike Riley @mriley This month, we turn the spotlight on Mike Riley, author of Portable Python Projects. Mike’s book ...
New
PragmaticBookshelf
Author Spotlight Rebecca Skinner @RebeccaSkinner Welcome to our latest author spotlight, where we sit down with Rebecca Skinner, auth...
New

Sub Categories: