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[API Proposal]: Vector.Create #94384
Description
Background and motivation
Currently, when we need to create a vector from a scalar or array, we do:
_ = Vector64.Create(42);
_ = Vector128.Create(42);
_ = Vector256.Create(42);
_ = Vector512.Create(42);
_ = new Vector2(42);
_ = new Vector3(42);
_ = new Vector4(42);
_ = new Vector<int>(42);I propose we add Create methods to Vector2/3/4 and Vector<> too for slightly better consistency.
API Proposal
namespace System.Numerics
{
public static class Vector
{
public static Vector<T> Create<T>(T value);
public static Vector<T> Create<T>(ReadOnlySpan<T> values);
public static Quaternion AsQuaternion(this Vector4 value);
public static Plane AsPlane(this Vector4 value);
public static Vector2 AsVector2(this Vector4 value);
public static Vector3 AsVector3(this Vector4 value);
public static Vector4 AsVector4(this Quaternion value);
public static Vector4 AsVector4(this Plane value);
public static Vector4 AsVector4(this Vector2 value);
public static Vector4 AsVector4(this Vector3 value);
public static Vector4 AsVector4Unsafe(this Vector2 value);
public static Vector4 AsVector4Unsafe(this Vector3 value);
}
public struct Vector2
{
public static Vector2 Create(float value);
public static Vector2 Create(float x, float y);
public static Vector2 Create(ReadOnlySpan<float> values);
}
public struct Vector3
{
public static Vector3 Create(float value);
public static Vector3 Create(float x, float y, float z);
public static Vector3 Create(Vector2 vector, float z);
public static Vector3 Create(ReadOnlySpan<float> values);
}
public struct Vector4
{
public static Vector4 Create(float value);
public static Vector4 Create(float x, float y, float z, float w);
public static Vector4 Create(Vector2 vector, float z, float w);
public static Vector4 Create(Vector3 vector, float w);
public static Vector4 Create(ReadOnlySpan<float> values);
}
}
namespace System.Runtime.Intrinsics
{
public static class Vector128
{
public static Vector128<float> AsVector128Unsafe(this Vector2 value);
public static Vector128<float> AsVector128Unsafe(this Vector3 value);
public static Vector128<float> AsVector128Unsafe(this Vector4 value);
}
}We might also add T[] values, int offset and Span<T> overloads.
API Usage
Vector<int> v = Vector.Create(42);Alternative Designs
No response
Risks
No response
Activity
EgorBo commentedon Nov 5, 2023
cc @tannergooding
MichalPetryka commentedon Nov 5, 2023
This'd probably be required for making them implement
ISimdVectoranyway?EgorBo commentedon Nov 6, 2023
Probably? if we plan to implement ISimdVector in VectorT
tannergooding commentedon Nov 6, 2023
That's part of the long term plan, yes. However, I don't think
ISimdVectorcan be made public without a language feature or two as we won't be able to correctly version it or expose some core APIs otherwise.bartonjs commentedon Jun 13, 2024
Video
Looks good as proposed
julealgon commentedon Jun 13, 2024
Do these
Createmethods only exist to workaround the lack of generic type inference on constructors? Or is there more to it?tannergooding commentedon Jun 13, 2024
They exist for parity with
Vector64/128/256/512<T>, so that they can be used with the eventual exposure of a newISimdVector<TSelf, T>(we have this internally already), and because they can provide a slight perf advantage and overall better IR/codegen due to operating byvalue instead of takingthisvia an implicit byref (which requires a block copy and the JIT to elide it).tannergooding commentedon Jun 17, 2024
This was resolved in #103462