tayloraswift / swift-noise Goto Github PK

It would be great if you could follow standard SPM conventions, e.g.

sources -> Sources
tests -> Tests
readme.md -> README.md

I'm getting consistent “Fatal error: Array index is out of range” crashes in GradientNoise2D's evaluate(_ x:Double, _ y:Double) at gradient.swift on line 540.

The issue seems to be that the staticGradientNoise2D.points is initialized to have 32 members on line 354 , then when evaluate(…) is called, base_vertex_index:Int ends up with value of 32 (Int((2*sample_uv_rel.y - sample_uv_rel.x - Double(a))*0.5 + 1) << 4 with sample_uv_rel = (1, 0) & a = 0 → Int((2*1 - 0 - Double(0))*0.5 + 1) << 4 → Int(2*0.5 + 1) << 4 → Int(2) << 4 → 32, on line 457).

Finally on line 540, the code attempts to iterate in a for loop over GradientNoise2D.points[base_vertex_index ..< base_vertex_index + 4]… so GradientNoise2D.points[32..<36] when GradientNoise2D.points is only 32 elements long.

I don't really know how this noise math is meant to work, so I can't speculate as to what a fix should be other than… missing modulus? IDK.

compiler bug: swiftlang/swift#60447

this module has fallen seriously out of maintenance, and needs to be revived

This is really not an issue but mostly an interrogation on my part.
I was wondering if I could generate dynamic noise background patterns and include them in my iOS app.

Questions:

1. Would that be feasible as far as rendering time?
2. Can I leverage the png creation capability of the tests and display the generated image directly in a view?
3. Would it be possible to seed the noise generator to support a light and dark pattern to follow the iOS app environment (light or dark)?

Thanks

I get a crash somewhat randomly when generating in a loop of tens of thousands of pixels.

Here's an example of some of the settings when it crashed. It doesn't seem to crash particularly reproducibly.

let noise = GradientNoise2D(amplitude: 1, frequency: 0.5, seed: 332)
noise.evaluate(-25.3217883662071, 43.793)

I (amazingly) cannot figure out how to copy the stack trace out of Xcode but it crashes on this line:

https://github.com/kelvin13/noise/blob/965fc23d7e95fb21a9065ef1566ee2bbd2b86e4b/sources/noise/gradient.swift#L540

with

2022-02-04 12:49:07.312857-0800 Run[53616:517701] Swift/Array.swift:405: Fatal error: Array index is out of range

part of #4

Your code currently doesn't handle the "extra vertices" from the original Open Simplex implementation, which will result in discontinuities at simplex boundaries. See here for further discussion: Razaekel/noise-rs#141 (comment)

the library somehow has a listing on swiftpackageindex.com. we should add the badges they generate for us