Post by carlyn - Takahē

Takahē

2y

Part 9: Okay, champion of the delaying tactic that I am… In order to understand USD I _have_ to make a Domain Specific Language for it? Riiight?? I used the attached code to make the attached image. The files it makes are still a bit of a puddle... but they do render.

https://www.whynotestflight.com/excuses/hello-usd-part-9-parlez-vous-multiball-dsl-starts-here/

#SwiftLang #Swift #GenerativeArt #CreativeCoding #OpenUSD #ResultBuilder #3D #DomainSpecificLanguage

$CODE ``` public struct MultiBallStage { public init(count:Int) { self.count = count } let count:Int let minTranslate = -4.0 let maxTranslate = 4.0 let minRadius = 0.8 let maxRadius = 2.0 public func buildStage() -> Canvas3D { Canvas3D { //blue origin sphere Sphere(radius: 1.0).color(red: 0, green: 0, blue: 1.0) //the multi in multiball for _ in 0..<count { Sphere(radius: Double.random(in: minRadius...maxRadius)) .color( red: Double.random(in: 0...1), green: Double.random(in: 0...1), blue: Double.random(in: 0...1) ) .translateBy(Vector.random(range: minTranslate...maxTranslate)) } } } } ```$

Screenshot of randomly sized, colored and placed spheres… AGAIN. Still 13 of them. New colors and new layout.

1 0 0 View Post & Replies See Original

2y

Part 10: Turns out yesterday was a Reading Day. I have the libraries up and running, but it’s time to truly get the picture as to why USD is even a thing, and what made Apple choose it. A lot of the existing literature is for VFX folks, which I am not, so in addition to my Top Pick references there’s some added color for programmers.

https://www.whynotestflight.com/excuses/hello-usd-part-10-reading-day/

If you watch nothing else (39 min): https://www.nvidia.com/en-us/on-demand/session/gtcspring23-s52054/

Top WAT: https://developer.nvidia.com/isaac-sim

#nVidiaUSD #USD #OpenUSD #ReadTheDocs

Edited 2y ago

1 0 0 View Post & Replies See Original

2y

Part 11: Wrote a Domain Specific Language... to write Domain Specific Languages! ha! An enum based tree and a Result Builder allowed me to write the attached code to produce the attached output.

playground ready code: https://gist.github.com/carlynorama/088fd2bb77cb9d4fabb0c55e50f780b5

process getting there: https://www.whynotestflight.com/excuses/hello-usd-part-11-gotta-make-it-easier-to-write-file-builders/

#SwiftLang, #DSL, #OpenUSD, #ResultBuilder, #Swift, #Enum, #DataStructures

<CODE> let document = Document {
"Header"
oneMoreDown
FunTag(content: bracketedMessage)
AttributedTag(name: "MEANING", attribute: 42) {
FunTag {
"Test"
bracketedMessage
}
}
Repeater(count: 3) {
"Hi!"
}
"Footer"
}

print(document.render())</CODE>

<CODE> <FUNTAG>
<p>
I have a message
</p>
</FUNTAG>
<MEANING attribute="42">
<FUNTAG>
Test
<p>
I have a message
</p>
</FUNTAG>
</MEANING>
Hi!
Hi!
Hi!
Footer
<FUNTAG><p>I have a message</p></FUNTAG><MEANING attribute="42"><FUNTAG>Test<p>I have a message</p></FUNTAG></MEANING>Hi!Hi!Hi!Footer </CODE>

1 0 0 View Post & Replies See Original

2y

Part 12: Applying Part 11 to the actual FileBuilder’s will make making adding features to my 3D model builder so much easier.

Case and point the `sphereBuilder` func from the X3D file is so much prettier now, and I can make my openUSD files use the expanded bracket style to their hearts content without having to manage the `\n\t\t` mess myself.

https://www.whynotestflight.com/excuses/hello-usd-part-12-lets-make-these-filebuilders-cleaner/

#SwiftLang #Swift #X3D #OpenUSD #String #ResultBuilders

$<CODE> @StringBuilder func sphereBuilder(shape:Sphere) -> String { if !shape.transformations.isEmpty { for transform in shape.transformations { transformStart(transform:transform) } } "<shape>" "\t<appearance>" if !shape.surfaces.isEmpty { materialString(shape.surfaces) } "\t</appearance>" "\t<sphere radius='\(shape.radius)'></sphere>" "</shape>" if !shape.transformations.isEmpty { for _ in 0..<shape.transformations.count { transformClose() } } } func transformStart(transform:Transformation) -> String { switch transform { case .translate(let v): return "<transform translation='\(v.x) \(v.y) \(v.z)'>" // default: // fatalError() } } func transformClose() -> String { "</transform>" } </CODE>$

$<CODE> func sphereBuilder(shape:Sphere) -> StringNodeable { var content = Tag("Shape") { Tag("Appearance") { if !shape.surfaces.isEmpty { //function unchanged from previous code for now //still needs updating at this point. materialString(shape.surfaces) } } "<Sphere radius='\(shape.radius)'></Sphere>" } if !shape.transformations.isEmpty { //Last closest to the content. let orderedTransforms = shape.transformations.reversed() for item in orderedTransforms { let attributes = transformAttribute(transform: item) content = Tag("Transform", attributes:attributes) { content } } } return content } func transformAttribute(transform:Transformation) -> Dictionary<String,String> { switch transform { case .translate(let v): return ["translation":"\(v.x) \(v.y) \(v.z)"] } } </CODE>$

$<CODE> func sphereBuilder(shape:Sphere) -> StringNodeable { CurlyBraced(opening: "def Xform \"\(shape.id)\"", style: .expanded) { if !shape.transformations.isEmpty { transformString(shape:shape) } CurlyBraced(opening: "def \(shape.shapeName) \"\(shape.id.lowercased())\"", style: .expanded) { "\(extentString(shape: shape))" if !shape.surfaces.isEmpty { colorString(shape:shape) } "\(radiusString(shape.radius))" } } </CODE>$

Edited 2y ago

1 0 0 View Post & Replies See Original

1y

“The best time to build a test was before the first commit. The next best time is now.” – Proverbious the Commitor, probably

https://www.whynotestflight.com/excuses/hello-usd-part-13-test-test-test/

#XCode #XCTest #SwiftLang #UnitTesting #Equatable

1 0 0 View Post & Replies See Original

1y

Part 14: Confirming everything runs on Linux with a GitHub Action and VM.

https://www.whynotestflight.com/excuses/hello-usd-part-14-now-to-get-github-to-run-the-tests/

#SwiftLang #SwiftOnLinux #GitHubActions

<code>
jobs:
build:
name: Build Linux
runs-on: ubuntu-latest
container:
image: swift:latest
steps:
- name: Checkout
uses: actions/checkout@v3
- name: Build
run: |
swift build -v
- name: Test
run: |
swift test -v
</code>

1 0 0 View Post & Replies See Original

1y

Part 15: Now, before I forget everything… Can a GitHub Action build and then cache OpenUSD? Yes, Virginia, it can.

EDIT: THE LINK!!! https://www.whynotestflight.com/excuses/hello-usd-part-15-can-a-github-action-cache-a-openusd-build/

#GitHubAction #Caching #OpenUSD

Screenshot of a GitHub repo’s Action cache control panel with several caches including one for a python build. Python caching not discussed in the article (yet?) but code available in the repo linked to in the article.

Edited 1y ago

1 0 0 View Post & Replies See Original

1y

Part 16: Duct-tape, string and pieces of gum all the way down, but I can make Swift, via Process(), run anything from a OpenUSD build I want!! usdcat, usdchecker, python scripts that import pxr... THE WORKS! **(MacOS & Linux only)

https://www.whynotestflight.com/excuses/hello-usd-part-16-swift-just-sipping-openusd-through...-a-pipe/

#OpenUSD #SwiftLang #shell #python

Composite of two screenshots: A text editor with basic hello world text, and a QuickView window with our friend the sphere, once again. The usda file was generated with the code in the other attached image.

$``` public func saveHelloWorld(to outputLocation:String) { let current = URL(string: #file) let dir = current!.deletingLastPathComponent() let message = try? shell("python3 \(dir)/python_scripts/hello_world.py \(outputLocation)") print("message:\(message ?? "no message")") } ```$

1 0 0 View Post & Replies See Original

1y

Part 17: In case anyone needs the data point, building OpenUSD on a Linux VM with only one processor allocated to it takes ~7 hours... BUT it did make it, and the code I thought would work on Linux is truly code I know works on Linux now:

https://www.whynotestflight.com/excuses/hello-usd-part-17-ill-build-openusd-on-my-vm-how-long-could-it-take/

#OpenUSD #Ubuntu #Linux #SwiftLang

Screenshot of Ubuntu desktop with VSCode open to USDTestingCLI.swift with the same output in the console as yesterday's post had from the MacOS build.

Edited 1y ago

1 0 0 View Post & Replies See Original

1y

Part 18: It's not all refactoring and compiling after all! Made a sphere… out of Spheres!!!

https://www.whynotestflight.com/excuses/hello-usd-part-18-i-can-make-a-sphere-out-of-spheres/

#SwiftLang #Swift #OpenUSD #x3d #GenerativeArt #CreativeCoding #sphere #fibonacci

A QuickLook screen shot of a Sphere, made out of Spheres! It uses a fibonacci spiral algorithm to do the positional layout. The colors are based on the magnitude of x, y and z coordinates.

<code>
func generatePoints(count:Int, radius:Double) -> [Vector] {
var points:[Vector] = []
for i in 0..<count {
let shiftedIndex = Double(i)+0.5

let polar:Double = acos(1 - 2*shiftedIndex/Double(count))
let azimuthal:Double = goldenAngle * shiftedIndex

// y-axis spindle instead.
points.append(Vector(
x: cos(azimuthal) * sin(polar),
y: cos(polar),
z: sin(azimuthal) * sin(polar)
).scaled(by: radius))
}
return points
} </code>

1 0 0 View Post & Replies See Original

1y

Part 19: Lat/Long layout was feeling left out. Had to go back and get it.

https://www.whynotestflight.com/excuses/hello-usd-part-19-i-just-plain-skipped-over-latitude-and-longitude/

#SwiftLang #Swift #OpenUSD #x3d #GenerativeArt #CreativeCoding #sphere

QuickLook window screenshot. Sphere of 82 spheres, each at a latitude/longtitude point. The spheres are sage/olive green at the top and blend to kind of perwinkle.

QuickLook window screenshot. Sphere of 82 spheres, each sphere ring is at slice point. The spheres are sage/olive green at the top and blend to kind of perwinkle.

1 0 0 View Post & Replies See Original

1y

Part 20: I do like the quaint charm of a usd in a QuickLook window, but wow, the png's from usdrecord are dreamy. Not a stray pixel anywhere. And the highlight! So pretty.

For those who are interested - it uses stb, not libpng, to get a large number of image formats for very little code debt.

https://www.whynotestflight.com/excuses/hello-usd-part-20-hello-usdrecord/

https://github.com/nothings/stb

#OpenUSD #png #codehunting #usdrecord

Two rings side by side, each made from a collection of rainbow colored spheres. The one on the left rests on the velvety black background of the image. The one of the right lives in a light gray box that betrays its origin as a screen grab from QuickLook. The spheres in that one have jagged, polygonal edges. The one on the left each sphere has dorodango levels of polish and care.

Edited 1y ago

1 0 0 View Post & Replies See Original

1y

Part 21: Inching forward on a refactor of the 3DCanvas so my usda file generator can do something other than Spheres! I'm not sure it’s the answer, but I did make a proof-of-concept SwiftUI/View style version. Modeled on work by @objcio (Thank you!)

https://www.whynotestflight.com/excuses/hello-usd-part-21-what-if-i-refactored-sketchpad-to-work-like-swiftui/

TL;DR: https://gist.github.com/carlynorama/3e6765d4a87aaaf3fe2f69abb14764ca

#SwiftLang #SwiftUI #FunWithResultBuilder

Code snippet that says it should never be called. Offered as humor. Actually real though. Lines 34-36 in linked gist.

1 0 0 View Post & Replies See Original

1y

Part 22: The transformation from Canvas -> Layer using a protocol based result builder is complete and now I can... drum roll please… still run multiball. But now I know about usdrecord so it’s prettier!

https://www.whynotestflight.com/excuses/hello-usd-part-22-the-control-flow-is-a-lie./

#SwiftLang #ResultBuilder #ForLoopMafia #OpenUSD

A collection of around a dozen spheres of various sizes and colors in a clump. This time it is not a screen shot of QuickLook so they’re all smooth and pretty on a transparent background.

0 0 0 View Post & Replies See Original