BabylonJS/Babylon.js · error · Error

Buffer access is out of range

Error message

Buffer access is out of range

What it means

glTF 1.0 loader utility GetBufferFromBufferView throws this when the requested byte range (bufferView.byteOffset + byteOffset through byteOffset + byteLength) exceeds the loaded buffer view's byteLength. It means the glTF asset references more bytes than the buffer actually provides — a corrupted or malformed asset.

Source

Thrown at packages/dev/loaders/src/glTF/1.0/glTFLoaderUtils.ts:183

            case ETextureFilterType.NEAREST_MIPMAP_NEAREST:
                return Texture.NEAREST_SAMPLINGMODE;
            default:
                return Texture.BILINEAR_SAMPLINGMODE;
        }
    }

    public static GetBufferFromBufferView(
        gltfRuntime: IGLTFRuntime,
        bufferView: IGLTFBufferView,
        byteOffset: number,
        byteLength: number,
        componentType: EComponentType
    ): ArrayBufferView {
        byteOffset = bufferView.byteOffset + byteOffset;

        const loadedBufferView = gltfRuntime.loadedBufferViews[bufferView.buffer];
        if (byteOffset + byteLength > loadedBufferView.byteLength) {
            throw new Error("Buffer access is out of range");
        }

        const buffer = loadedBufferView.buffer;
        byteOffset += loadedBufferView.byteOffset;

        switch (componentType) {
            case EComponentType.BYTE:
                return new Int8Array(buffer, byteOffset, byteLength);
            case EComponentType.UNSIGNED_BYTE:
                return new Uint8Array(buffer, byteOffset, byteLength);
            case EComponentType.SHORT:
                return new Int16Array(buffer, byteOffset, byteLength);
            case EComponentType.UNSIGNED_SHORT:
                return new Uint16Array(buffer, byteOffset, byteLength);
            default:
                return new Float32Array(buffer, byteOffset, byteLength);
        }
    }

View on GitHub (pinned to 0592b347b8)

Solutions

1. Re-export or re-download the glTF/binary assets to ensure they are not truncated
2. Validate the glTF with the glTF-Validator (Khronos) to find out-of-range accessors
3. Check that the .bin buffer matches the JSON-declared byteLength
4. If hand-editing, recompute accessor byteOffset/byteLength against bufferView bounds

Example fix

// before (hand-edited glTF JSON)
"accessors": [{ "bufferView": 0, "byteOffset": 512, "count": 10000, ... }] // exceeds bufferView
// after: re-export from the DCC tool so offsets/count match buffer size

function accessorFitsBufferView(accessor, bufferView) {
  const size = { 5120:1, 5121:1, 5122:2, 5123:2, 5125:4, 5126:4 }[accessor.componentType];
  const comps = { SCALAR:1, VEC2:2, VEC3:3, VEC4:4, MAT4:16 }[accessor.type];
  return accessor.byteOffset + accessor.count * comps * size <= bufferView.byteLength;
}

try {
  await BABYLON.SceneLoader.LoadAsync('./', 'model.gltf', engine);
} catch (e) {
  if (e instanceof Error && e.message === 'Buffer access is out of range') {
    console.error('glTF buffer/accessor out of bounds: asset is malformed or truncated');
  } else throw e;
}

When it happens

Trigger: Loading a glTF 1.0 file whose accessor byteOffset/byteLength/byteStride exceed the bufferView size, or whose buffer was truncated (incomplete download/embedded data shorter than declared).

Common situations: Hand-edited or tool-mangled glTF where byteOffsets were not recomputed; truncated .bin sidecar file; binary asset corrupted during upload/deployment; wrong buffer referenced in the JSON.

Related errors

• ${context}: ${error.message}
• ${extensionContext}: Gaussian splatting primitives must use
• ${extensionContext}: Gaussian splatting primitive is missing
• ${context}: Uri is missing or the binary glTF is missing its
• ${context}: Failed to find index (${index})

AI-assisted analysis of BabylonJS/Babylon.js@0592b347b8 (2026-08-30). Data as JSON: /api/errors/49093b33db7e15d6. Report an issue: GitHub.