What causes "${context}: Camera orthographic properties are missing" in BabylonJS/Babylon.js?

Fix the source glTF: add the orthographic block {xmag, ymag, znear, zfar} to the camera.

BabylonJS/Babylon.js · error · Error

${context}: Camera orthographic properties are missing

Error message

${context}: Camera orthographic properties are missing

What it means

When loading a glTF camera of type ORTHOGRAPHIC, the loader requires the camera JSON to contain an `orthographic` sub-object with xmag, ymag, znear, zfar. This error means the glTF declares camera.type == "orthographic" but the orthographic properties block is absent or null, so the loader cannot construct ortho bounds. It is a strict glTF schema violation guard.

Source

Thrown at packages/dev/loaders/src/glTF/2.0/glTFLoader.pure.ts:1725

        // glTF cameras look towards the local -Z axis.
        babylonCamera.setTarget(new Vector3(0, 0, -1));

        switch (camera.type) {
            case CameraType.PERSPECTIVE: {
                const perspective = camera.perspective;
                if (!perspective) {
                    throw new Error(`${context}: Camera perspective properties are missing`);
                }

                babylonCamera.fov = perspective.yfov;
                babylonCamera.minZ = perspective.znear;
                babylonCamera.maxZ = perspective.zfar || 0;
                break;
            }
            case CameraType.ORTHOGRAPHIC: {
                if (!camera.orthographic) {
                    throw new Error(`${context}: Camera orthographic properties are missing`);
                }

                babylonCamera.mode = Camera.ORTHOGRAPHIC_CAMERA;
                babylonCamera.orthoLeft = -camera.orthographic.xmag;
                babylonCamera.orthoRight = camera.orthographic.xmag;
                babylonCamera.orthoBottom = -camera.orthographic.ymag;
                babylonCamera.orthoTop = camera.orthographic.ymag;
                babylonCamera.minZ = camera.orthographic.znear;
                babylonCamera.maxZ = camera.orthographic.zfar;
                break;
            }
            default: {
                throw new Error(`${context}: Invalid camera type (${camera.type})`);
            }
        }

        GLTFLoader.AddPointerMetadata(babylonCamera, context);
        this._parent.onCameraLoadedObservable.notifyObservers(babylonCamera);

View on GitHub (pinned to 0592b347b8)

Solutions

Fix the source glTF: add the orthographic block {xmag, ymag, znear, zfar} to the camera.
Re-export the asset from the original DCC tool with correct camera settings.
Change the camera type to "perspective" with a perspective block if an ortho camera was not intended.
Pre-validate the glTF with a schema validator (e.g. glTF-Validator) before loading.

Example fix

// before (broken glTF JSON)
"cameras": [{ "type": "orthographic", "name": "cam" }]
// after
"cameras": [{ "type": "orthographic", "orthographic": { "xmag": 1, "ymag": 1, "znear": 0.1, "zfar": 100 }, "name": "cam" }]

Defensive patterns

Strategy: validation

Validate before calling

const cam = gltf.cameras?.[i];
if (cam?.type === "orthographic" && !cam.orthographic) {
  throw new Error(`Camera ${cam.name ?? i}: orthographic properties missing`);
}

Type guard

function hasOrtho(cam: { type: string; orthographic?: unknown }): cam is { type: "orthographic"; orthographic: { xmag: number; ymag: number; znear: number; zfar: number } } {
  return cam.type === "orthographic" && !!cam.orthographic;
}

Try / catch

try { await SceneLoader.ImportAsync(...); } catch (e) {
  if ((e as Error).message.includes("orthographic properties are missing")) {
    // fall back to a default camera or skip the asset
  }
}

Prevention

Run glTF-Validator on every asset in your pipeline (CI step).
Never hand-strip camera property blocks from glTF JSON.
Re-export cameras from the DCC tool rather than editing JSON by hand.

When it happens

Trigger: Parsing a glTF asset whose cameras[i] has type "orthographic" but no orthographic property (or it is null); typically produced by a broken exporter or hand-edited/trimmed glTF JSON.

Common situations: Hand-authored glTF files, assets post-processed by scripts that strip 'unused' properties, buggy exporters emitting the type string without the required data block, or a file corrupted during transmission.

Related errors

AI-assisted analysis of BabylonJS/Babylon.js@0592b347b8 (2026-08-30). Data as JSON: /api/errors/245f731aa088d294. Report an issue: GitHub.