What causes "Indices for Vector2 run from 0 to 1, inclusive." in stride3d/stride?

Validate the index is 0 or 1 before indexing.

stride3d/stride · error · ArgumentOutOfRangeException

Indices for Vector2 run from 0 to 1, inclusive.

Error message

Indices for Vector2 run from 0 to 1, inclusive.

What it means

The Vector2 indexer bounds-checks the index parameter and throws ArgumentOutOfRangeException when the index is not 0 or 1. It is a generic guard on component access: 0 maps to X and 1 to Y; since Vector2 has only two components, any other index is invalid.

Solutions

Validate the index is 0 or 1 before indexing.
Bound loops with 2 for Vector2 components.
Access X/Y properties directly when the component is known statically.

Example fix

// before
for (int i = 0; i < 3; i++) sum += v[i]; // Vector2 has only 2
// after
for (int i = 0; i < 2; i++) sum += v[i];

Defensive patterns

Strategy: validation

Validate before calling

if (index < 0 || index > 1)
    throw new ArgumentOutOfRangeException(nameof(index), "Vector2 index must be 0 or 1.");
var component = v[index];

Type guard

bool IsValidVector2Index(int i) => i == 0 || i == 1;

Try / catch

try
{
    component = v[index];
}
catch (ArgumentOutOfRangeException)
{
    component = 0f;
}

Prevention

Use X/Y properties instead of indexer for statically known components.
Bound component loops at 2 for Vector2.
Avoid sharing generic component-iteration helpers across different vector types without a count parameter.

When it happens

Trigger: Reading v[i] with i >= 2 or i < 0, e.g. a loop written for Vector3/Vector4 iterating 3-4 components of a Vector2.

Common situations: Generic shader-like component loops reused across vector types; computed indices from bad data; z-vector/z-buffer code copied from 3D examples.

Related errors

AI-assisted analysis of stride3d/stride@96fad776d2 (2026-09-14). Data as JSON: /api/errors/f3ba8f8e7a98f839. Report an issue: GitHub.

Appendix: source

Thrown at sources/core/Stride.Core.Mathematics/Vector2.cs:144

    /// <summary>
    /// Gets or sets the component at the specified index.
    /// </summary>
    /// <value>The value of the X or Y component, depending on the index.</value>
    /// <param name="index">The index of the component to access. Use 0 for the X component and 1 for the Y component.</param>
    /// <returns>The value of the component at the specified index.</returns>
    /// <exception cref="System.ArgumentOutOfRangeException">Thrown when the <paramref name="index"/> is out of the range [0, 1].</exception>
    public float this[int index]
    {
        get
        {
            switch (index)
            {
                case 0: return X;
                case 1: return Y;
            }

            throw new ArgumentOutOfRangeException(nameof(index), "Indices for Vector2 run from 0 to 1, inclusive.");
        }

        set
        {
            switch (index)
            {
                case 0: X = value; break;
                case 1: Y = value; break;
                default: throw new ArgumentOutOfRangeException(nameof(index), "Indices for Vector2 run from 0 to 1, inclusive.");
            }
        }
    }

    /// <summary>
    /// Casts from System.Numerics to Stride.Maths vectors
    /// </summary>
    /// <param name="v">Value to cast</param>
    public static implicit operator Vector2(System.Numerics.Vector2 v)

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