babalae/better-genshin-impact · error · InvalidOperationException

{fieldName} 必须是 1 到 4 个数字

Error message

{fieldName} 必须是 1 到 4 个数字

What it means

BuildScalar constructs an OpenCvSharp Scalar for the lowerColor/upperColor color-range filters and supports only 1 to 4 channel values. If the JSON array is empty or has more than four entries, InvalidOperationException is thrown because a Scalar cannot represent that many channels.

Source

Thrown at BetterGenshinImpact/Core/Recognition/RecognitionObjectJsonLoader.cs:490

        private static Rect BuildRect(object? x, object? y, object? width, object? height)
        {
            return new Rect(
                (int)Math.Round(ToDouble(x)),
                (int)Math.Round(ToDouble(y)),
                (int)Math.Round(ToDouble(width)),
                (int)Math.Round(ToDouble(height)));
        }

        private static Scalar BuildScalar(IReadOnlyList<double> values, string fieldName)
        {
            return values.Count switch
            {
                1 => new Scalar(values[0]),
                2 => new Scalar(values[0], values[1]),
                3 => new Scalar(values[0], values[1], values[2]),
                4 => new Scalar(values[0], values[1], values[2], values[3]),
                _ => throw new InvalidOperationException($"{fieldName} 必须是 1 到 4 个数字"),
            };
        }

        private static TEnum ParseEnumExact<TEnum>(string? value, string fieldName) where TEnum : struct, Enum
        {
            if (string.IsNullOrWhiteSpace(value))
            {
                throw new InvalidOperationException($"{fieldName} 不能为空");
            }

            if (Enum.TryParse<TEnum>(value, false, out var parsed))
            {
                return parsed;
            }

            throw new InvalidOperationException($"{fieldName} 的值 {value} 不是有效的 {typeof(TEnum).Name}");
        }

View on GitHub (pinned to a7cb36712d)

Solutions

1. Provide exactly 1 to 4 numeric values for lowerColor/upperColor.
2. Match the element count to the color space (e.g. 3 for BGR).
3. Validate the array length against the Scalar channel limit before runtime.

Example fix

// before
// "lowerColor": [100, 100, 100, 100, 100]  -> throws

// after
// "lowerColor": [100, 100, 100]

static void AssertScalarShape(IReadOnlyList<double> values, string fieldName)
{
    if (values.Count is < 1 or > 4)
        throw new InvalidOperationException($"{fieldName} must have 1-4 values, got {values.Count}.");
}

AssertScalarShape(config.LowerColor, nameof(config.LowerColor));
AssertScalarShape(config.UpperColor, nameof(config.UpperColor));

static bool IsValidScalar(IReadOnlyList<double> values) => values.Count is >= 1 and <= 4;

try { return RecognitionObjectJsonLoader.Load(config, objectName, context); }
catch (InvalidOperationException ex) when (ex.Message.Contains("必须是 1 到 4 个数字"))
{ Logger.LogError(ex, "Color scalar has invalid channel count."); throw; }

When it happens

Trigger: A RecognitionObject has "lowerColor": [] or "lowerColor": [0,0,0,0,0] (five values) in Recognition.json.

Common situations: Misunderstood channel count for the colorspace; accidentally added an alpha channel; pasted a 5+ element array from another tool.

Related errors

• 未找到名称为 {objectName} 的 RecognitionObject 配置
• 对象 {objectName} 缺少 template 配置
• 表达式 {expression} 未返回 Rect
• 变量 {name} 存在循环引用
• {fieldName} 不能为空

AI-assisted analysis of babalae/better-genshin-impact@a7cb36712d (2026-08-13). Data as JSON: /api/errors/90502bea80f1fecb. Report an issue: GitHub.