Id rename SquareRoot for consistency with existing symbols in the bcl

Kkhitiara Id rename SquareRoot for consistency with existing symbols in the bcl

M

Maxine•10/21/23, 8:30 PM

System.Numerics uses Sqrt

M

Maxine•10/21/23, 8:30 PM

wait

M

Maxine•10/21/23, 8:30 PM

no system.numerics uses SquareRoot. huh

Kkhitiara first comment from me already is why does LengthSquared need a new type? requiri...

M

Maxine•10/21/23, 8:31 PM

what do you mean by new type

M

Maxine•10/21/23, 8:31 PM

(x*x)+(y*y)+(z*z) is very likely to overflow with integer types

M

Maxine•10/21/23, 8:31 PM

so yeah i could jsut leave that burden onto the user, but that is 90% likely a mistake

M

Maxine•10/21/23, 8:32 PM

same as DistanceSquared

P

Perksey•10/21/23, 8:37 PM

Given that we have both Point and Vector, surely the latter is assumed to be euclidean and therefore should have length stuff ergo being float only, not just any INumber?
readonly structs all the way, especially now we have withers
definitely prefer static methods on non-generic types, this was an explicit choice in Silk.NET.Maths so that you wouldn't need to repeat the generic unless you absolutely had to
```
thing = Vector2.Abs(thing)
```
thing = Vector2.Abs(thing)
```
thing = Vector2.Abs(thing)
```
thing = Vector2.Abs(thing)
is much cleaner than
```
thing = Vector2<T>.Abs(thing)
```
thing = Vector2<T>.Abs(thing)
```
thing = Vector2<T>.Abs(thing)
```
thing = Vector2<T>.Abs(thing)
. in most cases extension methods just work also, but you do raise a good point that sometimes you will have to repeat the generic but i'm okay with this.
not related to the proposal, but do BigInteger and Complex have the generic maths interfaces implemented? Silk.NET.Maths supports these today.
```
#if NET8_0
```
#if NET8_0
```
#if NET8_0
```
#if NET8_0
this is assumed if we're targeting 3.0. 3.0 will target the latest even-numbered SDK at time of release.
happy with
```
Sqrt
```
Sqrt
```
Sqrt
```
Sqrt
instead of
```
SquareRoot
```
SquareRoot
```
SquareRoot
```
SquareRoot
. generally prefer the names that we've used in
```
Silk.NET.Maths
```
Silk.NET.Maths
```
Silk.NET.Maths
```
Silk.NET.Maths
because we've already bikeshedded these.
```
Because the type of T has to be narrowed to IFloatingPointIeee754<T>, we can't actually implement the interface on Vector3<T>.
```
Because the type of T has to be narrowed to IFloatingPointIeee754<T>, we can't actually implement the interface on Vector3<T>.
```
Because the type of T has to be narrowed to IFloatingPointIeee754<T>, we can't actually implement the interface on Vector3<T>.
```
Because the type of T has to be narrowed to IFloatingPointIeee754<T>, we can't actually implement the interface on Vector3<T>.
I don't think Silk.NET.Maths ever did support Vector-as-Scalar as we had once thought of doing (i.e. allowing
```
Scalar.Add<Vector3<float>>(l, r)
```
Scalar.Add<Vector3<float>>(l, r)
```
Scalar.Add<Vector3<float>>(l, r)
```
Scalar.Add<Vector3<float>>(l, r)
) so we can live with this. it's cursed anyway.
```
Ideally, this should be vectorized. In practice, that's a lot of work.
```
Ideally, this should be vectorized. In practice, that's a lot of work.
```
Ideally, this should be vectorized. In practice, that's a lot of work.
```
Ideally, this should be vectorized. In practice, that's a lot of work.
no more work than we were prepared to do for 2.0
```
Extension 3: INumber<Vector3<T>> Implementation
```
Extension 3: INumber<Vector3<T>> Implementation
```
Extension 3: INumber<Vector3<T>> Implementation
```
Extension 3: INumber<Vector3<T>> Implementation
yeah I guess?
```
Extension 4: Directional static properties
```
Extension 4: Directional static properties
```
Extension 4: Directional static properties
```
Extension 4: Directional static properties
if we're doing something like this it should be an extension method that allows the specification of the coordinate system, not a simple property.
```
Extension 5: Convenience methods
```
Extension 5: Convenience methods
```
Extension 5: Convenience methods
```
Extension 5: Convenience methods
yep fine
```
Extension 6: IUtf8SpanFormattable (.NET 8)
```
Extension 6: IUtf8SpanFormattable (.NET 8)
```
Extension 6: IUtf8SpanFormattable (.NET 8)
```
Extension 6: IUtf8SpanFormattable (.NET 8)
if someone's willing to do it then yeah
```
Implicit cast to Vector2<T>, drop the Z component
```
Implicit cast to Vector2<T>, drop the Z component
```
Implicit cast to Vector2<T>, drop the Z component
```
Implicit cast to Vector2<T>, drop the Z component
should be explicit
generally make sure you have API parity with Silk.NET.Maths. Silk.NET.Maths is the one area where we don't actually need to do any surface API changes (generic maths notwithstanding) because it's pretty solid, and changing anything here would do weird things to user expectations.

obviously none of the above is the official working group stance, make sure you follow the proposal process documented in

documentation/proposals

documentation/proposals

documentation/proposals

documentation/proposals and make a more formal proposal like the WIP one in #1727, making rationale and alternatives (and the discussion points thereof) clear; if you want this in 3.0

P

Perksey•10/21/23, 8:39 PM

cc @kaijellinghaus the maths lord wrt https://gist.github.com/uwx/ee881028f5068f5c0ff29485051a1209

M

Maxine•10/21/23, 8:42 PM

The motivation with all of this was to allow Vector3<T> to use int for storage while still returning float for methods like Length(), which is a rare but useful use-case. The extension methods for IFloatingPoint<T> allow you to not have to specify the return type
ok
so from options 1-4 which is your personal preference?
yes for BigInteger, Complex only implements INumberBase, i can broaden the scope of T if desired
noted
noted
noted
i don't understand what you meant by this
noted
noted
noted
i already implemented it
noted
noted

K

Kai•10/21/23, 8:43 PM

I'll look once home.
Only thing I want to point out is that Silk maths is the only lib were we didn't really pay attention in the working group tbh. We've revised and been unhappy with many things so do also take everything there with a grain of salt. Overall it's solid of course.

M

Maxine•10/21/23, 8:43 PM

"no more work than we were prepared to do for 2.0" does that mean you're open to implementing it, or don't want to do it because it's not worth it?

P

Perksey•10/21/23, 8:43 PM

yes open to implementing, vectorization is actually called out in the approved 3.0 SDP

M

Maxine•10/21/23, 8:44 PM

we can copy tanner's existing code for some operators, others will have to be done from scratch

M

Maxine•10/21/23, 8:44 PM

maybe could coordinate to share code with them?

K

Kai•10/21/23, 8:45 PM

Only from perkseys comments - do consider thinking about separating maths and geometry. Graphic programmers often put those together, but a vector and a point are very different.
Also, my stance has always been that we should allow the user to do things even if we think it's not such a good idea, ie VectorN<sbyte>

M

Maxine•10/21/23, 8:45 PM

P

Perksey•10/21/23, 8:45 PM

it's worth noting @tannergooding often attends working group meetings, and will probably want any discussions we have here to feed into whatever system.numerics does down the line

P

Perksey•10/21/23, 8:45 PM

so code sharing can probably be discussed there as well. i mean it's all .NET Foundation code really, so reuse is trivial.
but it's nice if there's prior art to inform what questions need to be asked and answered for the .NET API Review

M

Maxine•10/21/23, 8:46 PM

no one said i couldn't do this

M

Maxine•10/21/23, 8:46 PM

(for real, why isn't this public???)

P

Perksey•10/21/23, 8:48 PM

i mean, isn't that trivial to implement

P

Perksey•10/21/23, 8:48 PM

it's public in NumberFormatInfo, just not TChar

M

Maxine•10/21/23, 8:49 PM

that would require encoding, which allocates in a supposedly allocation-less API, so we wanna cache, so we wanna use a weak table...

K

khitiaraOP•10/21/23, 8:49 PM

if doing utf8spanformattable remember utf8.trywrite for efficiency and interpolation and also consider implementing the other formattable-related interfaces

P

Perksey•10/21/23, 8:49 PM

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        internal ReadOnlySpan<TChar> NumberGroupSeparatorTChar<TChar>() where TChar : unmanaged, IUtfChar<TChar>
        {
            Debug.Assert(typeof(TChar) == typeof(char) || typeof(TChar) == typeof(byte));
            return typeof(TChar) == typeof(char) ?
                MemoryMarshal.Cast<char, TChar>(_numberGroupSeparator) :
                MemoryMarshal.Cast<byte, TChar>(_numberGroupSeparatorUtf8 ??= Encoding.UTF8.GetBytes(_numberGroupSeparator));
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        internal ReadOnlySpan<TChar> NumberGroupSeparatorTChar<TChar>() where TChar : unmanaged, IUtfChar<TChar>
        {
            Debug.Assert(typeof(TChar) == typeof(char) || typeof(TChar) == typeof(byte));
            return typeof(TChar) == typeof(char) ?
                MemoryMarshal.Cast<char, TChar>(_numberGroupSeparator) :
                MemoryMarshal.Cast<byte, TChar>(_numberGroupSeparatorUtf8 ??= Encoding.UTF8.GetBytes(_numberGroupSeparator));
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        internal ReadOnlySpan<TChar> NumberGroupSeparatorTChar<TChar>() where TChar : unmanaged, IUtfChar<TChar>
        {
            Debug.Assert(typeof(TChar) == typeof(char) || typeof(TChar) == typeof(byte));
            return typeof(TChar) == typeof(char) ?
                MemoryMarshal.Cast<char, TChar>(_numberGroupSeparator) :
                MemoryMarshal.Cast<byte, TChar>(_numberGroupSeparatorUtf8 ??= Encoding.UTF8.GetBytes(_numberGroupSeparator));
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        internal ReadOnlySpan<TChar> NumberGroupSeparatorTChar<TChar>() where TChar : unmanaged, IUtfChar<TChar>
        {
            Debug.Assert(typeof(TChar) == typeof(char) || typeof(TChar) == typeof(byte));
            return typeof(TChar) == typeof(char) ?
                MemoryMarshal.Cast<char, TChar>(_numberGroupSeparator) :
                MemoryMarshal.Cast<byte, TChar>(_numberGroupSeparatorUtf8 ??= Encoding.UTF8.GetBytes(_numberGroupSeparator));
        }

M

Maxine•10/21/23, 8:49 PM

but the group separator format can be reset, so we need to make sure to check if it's up to date when we pull from the weak table, and also it needs to be thread-safe...

Kkhitiara if doing utf8spanformattable remember utf8.trywrite for efficiency and interpola...

M

Maxine•10/21/23, 8:50 PM

did you read my code

M

Maxine•10/21/23, 8:50 PM

i am using Utf8.TryWrite

K

khitiaraOP•10/21/23, 8:50 PM

haven't had time

but good

MMaxine 1. The motivation with all of this was to allow Vector3<T> to use int for storag...

K

Kai•10/21/23, 8:50 PM

Kinda sniped by 1. here. I always wanted to have the ability to have ops have the ability to have a storage precision and each op have a specified precision.
Iirc there's lots of gains to have.

K

khitiaraOP•10/21/23, 8:50 PM

I thought my being busy as hell was over and then nope heck me I guess

M

Maxine•10/21/23, 8:51 PM

worst part is having to manually call TryWriteInterpolatedStringHandler because interpolated strings can't natively do what the API needs them to

K

khitiaraOP•10/21/23, 8:51 PM

wait really?

M

Maxine•10/21/23, 8:51 PM

oh yeah: and i have to allocate a

new string(format)

new string(format)

new string(format)

new string(format) because the string handler can't take a span<char>

K

Kai•10/21/23, 8:51 PM

Ie (wrong types for clarity)

VectorN.Dot<i8, f8>(a, b)

VectorN.Dot<i8, f8>(a, b)

VectorN.Dot<i8, f8>(a, b)

VectorN.Dot<i8, f8>(a, b)

KKai Only from perkseys comments - do consider thinking about separating maths and ge...

P

Perksey•10/21/23, 8:51 PM

this stance does fundamentally change the proposal, and as much as i have agreed in the past, given that we have strict rules codified in the BCL now in the form of the generic maths interfaces, it makes sense to follow them given they're the stewards of the ecosystem

MMaxine oh yeah: and i have to allocate a `new string(format)` because the string handle...

M

Maxine•10/21/23, 8:52 PM

(could rewrite the interpolated string handler, but...)