stride3d/stride · error · ArgumentOutOfRangeException

SigmaRatio cannot be < 0.0f

Error message

SigmaRatio cannot be < 0.0f

What it means

Thrown by the GaussianBlur.SigmaRatio setter when the assigned value is less than 0. SigmaRatio converts the radius into the Gaussian sigma (sigma = radius / SigmaRatio); a negative ratio yields an invalid sigma and an unusable blur kernel, so the setter rejects it with ArgumentOutOfRangeException.

Solutions

1. Clamp: SigmaRatio = Math.Max(0f, value)
2. Fix the source formula/config producing the negative value
3. Use the default ratio by not setting the property

Example fix

// before
blur.SigmaRatio = ratio;
// after
blur.SigmaRatio = Math.Max(0f, ratio);

if (ratio < 0f) ratio = 0f; blur.SigmaRatio = ratio;

bool IsValidSigmaRatio(float r) => r >= 0f && !float.IsNaN(r);

try { blur.SigmaRatio = value; } catch (ArgumentOutOfRangeException) { blur.SigmaRatio = 0f; }

When it happens

Trigger: Assigning a negative value to GaussianBlur.SigmaRatio, e.g. via a sign error in a formula or a config that accepts signed numbers.

Common situations: Loading sigma ratio from user/config data without validation; inverting a value that shouldn't be inverted; template parameters propagating a negative tuning constant.

Related errors

• Radius cannot be < 1
• DoF configuration needs at least one blur level!
• Last blurriest level must have a CoC of 1.0!
• levelCoCValues and levelDownscaleFactors must be arrays of…
• Radius cannot be < 0

AI-assisted analysis of stride3d/stride@96fad776d2 (2026-09-14). Data as JSON: /api/errors/52f3d235bc815dd6. Report an issue: GitHub.

Appendix: source

Thrown at sources/engine/Stride.Rendering/Rendering/Images/GaussianBlur/GaussianBlur.cs:82

        /// <summary>
        /// Gets or sets the sigma ratio. The sigma ratio is used to calculate the sigma based on the radius: The actual
        /// formula is <c>sigma = radius / SigmaRatio</c>. The default value is 2.0f.
        /// </summary>
        /// <value>The sigma ratio.</value>
        /// <userdoc>The sigma ratio of the Gaussian. The sigma ratio is used to calculate the sigma of the Gaussian. 
        /// The actual formula is <c>sigma = radius / SigmaRatio</c></userdoc>
        [DataMember(20)]
        public float SigmaRatio
        {
            get
            {
                return sigmaRatio;
            }
            set
            {
                if (value < 0.0f)
                {
                    throw new ArgumentOutOfRangeException("SigmaRatio cannot be < 0.0f");
                }

                sigmaRatio = value;
            }
        }

        public void Collect(RenderContext context)
        {
        }

        protected override void DrawCore(RenderDrawContext context)
        {
            // Find gaussian blur shader (if same radius has already been used)
            GaussianBlurShader matchingGaussianBlurShader = null;
            foreach (var gaussianBlurShader in shaders)
            {
                if (gaussianBlurShader.Radius == Radius)
                {

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