animateModelOddEven.ts

import Scene from 'Scene';
import FaceTracking from 'FaceTracking';
import Animation from 'Animation';

/*
Model structure:
- Model
    - skeleton (null)
        - Armatures (null objs)
            - Petal & pollen (meshes)
            - Bone*000
            - Bone*[ODD]
                - Bone*[EVEN]
*/

(async function () {
    let modelRotationSignalValues: {[key: string]: number[]} = {};

    // Get all scene objects
    const [armatures, bones]: SceneObjectBase[][] = await Promise.all([
        Scene.root.findByPath('**/skeleton/Arm*'),
        Scene.root.findByPath('**/skeleton/**/Bone*'),
    ]);

    // Sort
    bones.sort((a, b) => {
        return a.name.localeCompare(b.name);
    });

    // Store the value of the model bone rotations
    bones.forEach(b=>{
        modelRotationSignalValues[b.name] = [
            b.transform.rotationX.pinLastValue(),
            b.transform.rotationY.pinLastValue(),
            b.transform.rotationZ.pinLastValue(),
        ];
    });
    
    // Star antenna :)
    const faceSignalX = FaceTracking.face(0).cameraTransform.x.expSmooth(100);
    const faceSignalX2 = FaceTracking.face(0).cameraTransform.x.expSmooth(96);
    const faceSignalY = FaceTracking.face(0).cameraTransform.y.expSmooth(100);
    const faceSignalY2 = FaceTracking.face(0).cameraTransform.y.expSmooth(96);
    const generalScaleFactor = -3000;

    bones.forEach((b, i)=>{
        // Ignore the first bone of every armature
        if (b.name.indexOf('000') != -1) return;

        // Factor depending on the bone position
        // The bones close to the tip of the petal should move more up and down, and less side to side
        let boneFactor: number = Number(b.name.slice(-3)) % 2;

        let boneFactorX = Math.max(1 - boneFactor, 0.5) * generalScaleFactor * 0.5;
        let boneFactorZ = boneFactor * generalScaleFactor * 0.35;

        let signalX = faceSignalY2.sub(faceSignalY).mul(boneFactorX);
        let signalZ = faceSignalX2.sub(faceSignalX).mul(boneFactorZ);

        b.transform.rotationX = signalX.add(signalZ.abs())  .add(modelRotationSignalValues[b.name][0]);
        b.transform.rotationZ = signalZ.neg()               .add(modelRotationSignalValues[b.name][2]);

    });

})();