dotnet/wpf · error · ArgumentOutOfRangeException

SR.InvalidPressureValue

Error message

SR.InvalidPressureValue

What it means

The StylusPoint constructor throws ArgumentOutOfRangeException when the pressureFactor is NaN, negative, or greater than 1.0. Pressure is stored as a float in the normalized range [0, 1]; values outside it are meaningless, so the constructor rejects them (unless validation is disabled internally, as in StylusPointDescription.Reformat).

Solutions

1. Normalize raw pressure to [0,1]: pressureFactor = rawPressure / maxPressure.
2. Clamp: Math.Clamp(rawPressure, 0f, 1f) before constructing.
3. Catch ArgumentOutOfRangeException if untrusted pressure data must be handled gracefully.

Example fix

// before
var point = new StylusPoint(x, y, rawPressure);
// after
float pressure = Math.Clamp(rawPressure / 1024f, 0f, 1f);
var point = new StylusPoint(x, y, pressure);

if (float.IsNaN(pressureFactor) || pressureFactor < 0f || pressureFactor > 1f)
    throw new ArgumentException("pressureFactor must be in [0,1]");

static bool IsValidPressure(float p) => !float.IsNaN(p) && p >= 0f && p <= 1f;

try { var p = new StylusPoint(x, y, pf, desc, vals); }
catch (ArgumentOutOfRangeException ex) when (ex.ParamName == "pressureFactor") { /* clamp and retry */ }

When it happens

Trigger: Calling new StylusPoint(x, y, pressureFactor, ...) with a pressureFactor that is float.NaN, < 0.0f, or > 1.0f.

Common situations: Passing raw device pressure (e.g. 0-1024 or 0-255 integer ranges) without normalizing to 0..1, or NaN from uninitialized float fields.

Understand the failure class

Background: "value must be between 0 and 1" / "out of range" / "must not be negative" errors: fixing range-validation failures across open-source libraries — this error's family across 42 libraries.

Related errors

• SR.InvalidMinMaxForButton
• SR.InvalidStylusPointXYNaN
• Argument out of range (end not contained in view)
• Argument out of range (position does not map to a line)
• Argument out of range (start not contained in view)

AI-assisted analysis of dotnet/wpf@81131a70a4 (2026-09-14). Data as JSON: /api/errors/47cba05ee27d5999. Report an issue: GitHub.

Appendix: source

Thrown at src/Microsoft.DotNet.Wpf/src/PresentationCore/System/Windows/Input/Stylus/Common/StylusPoint.cs:84

            int[] additionalValues, 
            bool validateAdditionalData,
            bool validatePressureFactor)
        {
            if (Double.IsNaN(x))
            {
                throw new ArgumentOutOfRangeException(nameof(x), SR.InvalidStylusPointXYNaN);
            }
            if (Double.IsNaN(y))
            {
                throw new ArgumentOutOfRangeException(nameof(y), SR.InvalidStylusPointXYNaN);
            }


            //we don't validate pressure when called by StylusPointDescription.Reformat
            if (validatePressureFactor &&
                (pressureFactor == Single.NaN || pressureFactor < 0.0f || pressureFactor > 1.0f))
            {
                throw new ArgumentOutOfRangeException(nameof(pressureFactor), SR.InvalidPressureValue);
            }
            //
            // only accept values between MaxXY and MinXY
            // we don't throw when passed a value outside of that range, we just silently trunctate
            //
            _x = GetClampedXYValue(x);
            _y = GetClampedXYValue(y);
            _stylusPointDescription = stylusPointDescription;
            _additionalValues = additionalValues;
            _pressureFactor = pressureFactor;

            if (validateAdditionalData)
            {
                //
                // called from the public verbose ctor
                //
                ArgumentNullException.ThrowIfNull(stylusPointDescription);

View on GitHub (pinned to 81131a70a4)