orbit-camera.js

// orbit-camera.js

var OrbitCamera = pc.createScript('orbitCamera');

// Camera attributes
OrbitCamera.attributes.add('distanceMax', { type: 'number', default: 20, title: 'Distance Max' });
OrbitCamera.attributes.add('distanceMin', { type: 'number', default: 1, title: 'Distance Min' });
OrbitCamera.attributes.add('pitchAngleMax', { type: 'number', default: 90, title: 'Pitch Angle Max (degrees)' });
OrbitCamera.attributes.add('pitchAngleMin', { type: 'number', default: 0, title: 'Pitch Angle Min (degrees)' });
OrbitCamera.attributes.add('yawAngleMax', { type: 'number', default: 360, title: 'Yaw Angle Max (degrees)' });
OrbitCamera.attributes.add('yawAngleMin', { type: 'number', default: -360, title: 'Yaw Angle Min (degrees)' });
OrbitCamera.attributes.add('minY', { type: 'number', default: 0, title: 'Minimum Y', description: 'Minimum Y value for camera world position' });

OrbitCamera.attributes.add('inertiaFactor', { type: 'number', default: 0.2, title: 'Inertia Factor' });
OrbitCamera.attributes.add('focusEntity', { type: 'entity', title: 'Focus Entity' });
OrbitCamera.attributes.add('frameOnStart', { type: 'boolean', default: true, title: 'Frame on Start' });

Object.defineProperty(OrbitCamera.prototype, 'distance', {
    get: function () { return this._targetDistance; },
    set: function (value) { this._targetDistance = this._clampDistance(value); }
});

Object.defineProperty(OrbitCamera.prototype, 'orthoHeight', {
    get: function () { return this.entity.camera.orthoHeight; },
    set: function (value) { this.entity.camera.orthoHeight = Math.max(0, value); }
});

Object.defineProperty(OrbitCamera.prototype, 'pitch', {
    get: function () { return this._targetPitch; },
    set: function (value) { this._targetPitch = this._clampPitchAngle(value); }
});

Object.defineProperty(OrbitCamera.prototype, 'yaw', {
    get: function () { return this._targetYaw; },
    set: function (value) { this._targetYaw = this._clampYawAngle(value); }
});

Object.defineProperty(OrbitCamera.prototype, 'pivotPoint', {
    get: function () { return this._pivotPoint; },
    set: function (value) { this._pivotPoint.copy(value); }
});

OrbitCamera.prototype.focus = function (focusEntity) {
    this._buildAabb(focusEntity);
    var halfExtents = this._modelsAabb.halfExtents;
    var radius = Math.max(halfExtents.x, Math.max(halfExtents.y, halfExtents.z));
    this.distance = (radius * 1.5) / Math.sin(0.5 * this.entity.camera.fov * pc.math.DEG_TO_RAD);
    this._removeInertia();
    this._pivotPoint.copy(this._modelsAabb.center);
};

OrbitCamera.distanceBetween = new pc.Vec3();

OrbitCamera.prototype.resetAndLookAtPoint = function (resetPoint, lookAtPoint) {
    this.pivotPoint.copy(lookAtPoint);
    this.entity.setPosition(resetPoint);
    this.entity.lookAt(lookAtPoint);
    var distance = OrbitCamera.distanceBetween;
    distance.sub2(lookAtPoint, resetPoint);
    this.distance = distance.length();
    this.pivotPoint.copy(lookAtPoint);
    var cameraQuat = this.entity.getRotation();
    this.yaw = this._calcYaw(cameraQuat);
    this.pitch = this._calcPitch(cameraQuat, this.yaw);
    this._removeInertia();
    this._updatePosition();
};

OrbitCamera.prototype.resetAndLookAtEntity = function (resetPoint, entity) {
    this._buildAabb(entity);
    this.resetAndLookAtPoint(resetPoint, this._modelsAabb.center);
};

OrbitCamera.prototype.reset = function (yaw, pitch, distance) {
    this.pitch = pitch;
    this.yaw = yaw;
    this.distance = distance;
    this._removeInertia();
};

OrbitCamera.prototype.resetToPosition = function (position, lookAtPoint) {
    this.entity.setPosition(position);
    this.entity.lookAt(lookAtPoint);
    this._pivotPoint.copy(lookAtPoint);
    var distanceVec = new pc.Vec3();
    distanceVec.sub2(position, lookAtPoint);
    this._targetDistance = this._distance = distanceVec.length();
    var cameraQuat = this.entity.getRotation();
    this._targetYaw = this._yaw = this._calcYaw(cameraQuat);
    this._targetPitch = this._pitch = this._calcPitch(cameraQuat, this._yaw);
    this._removeInertia();
    this._updatePosition();
};

// ==== Clamp helper for panning/orbiting so camera never under minY ====
OrbitCamera.prototype.worldCameraYForPivot = function(pivot) {
    var quat = new pc.Quat();
    quat.setFromEulerAngles(this._pitch, this._yaw, 0);
    var forward = new pc.Vec3();
    quat.transformVector(pc.Vec3.FORWARD, forward);
    var camPos = pivot.clone();
    camPos.add(forward.clone().scale(-this._distance));
    return camPos.y;
};

////////////////////////////////////////////////////////////////////////////////
//                          Private Methods                                   //
////////////////////////////////////////////////////////////////////////////////

OrbitCamera.prototype.initialize = function () {
    var self = this;
    var onWindowResize = function () { self._checkAspectRatio(); };
    window.addEventListener('resize', onWindowResize, false);
    this._checkAspectRatio();
    this._modelsAabb = new pc.BoundingBox();
    this._buildAabb(this.focusEntity || this.app.root);
    this.entity.lookAt(this._modelsAabb.center);
    this._pivotPoint = new pc.Vec3();
    this._pivotPoint.copy(this._modelsAabb.center);
    var cameraQuat = this.entity.getRotation();
    this._yaw = this._calcYaw(cameraQuat);
    this._pitch = this._clampPitchAngle(this._calcPitch(cameraQuat, this._yaw));
    this.entity.setLocalEulerAngles(this._pitch, this._yaw, 0);
    this._distance = 0;
    this._targetYaw = this._yaw;
    this._targetPitch = this._pitch;
    if (this.frameOnStart) {
        this.focus(this.focusEntity || this.app.root);
    } else {
        var distanceBetween = new pc.Vec3();
        distanceBetween.sub2(this.entity.getPosition(), this._pivotPoint);
        this._distance = this._clampDistance(distanceBetween.length());
    }
    this._targetDistance = this._distance;
    this.on('attr:distanceMin', function (value, prev) { this._distance = this._clampDistance(this._distance); });
    this.on('attr:distanceMax', function (value, prev) { this._distance = this._clampDistance(this._distance); });
    this.on('attr:pitchAngleMin', function (value, prev) { this._pitch = this._clampPitchAngle(this._pitch); });
    this.on('attr:pitchAngleMax', function (value, prev) { this._pitch = this._clampPitchAngle(this._pitch); });
    this.on('attr:focusEntity', function (value, prev) {
        if (this.frameOnStart) { this.focus(value || this.app.root); }
        else { this.resetAndLookAtEntity(this.entity.getPosition(), value || this.app.root); }
    });
    this.on('attr:frameOnStart', function (value, prev) {
        if (value) { this.focus(this.focusEntity || this.app.root); }
    });
    this.on('destroy', function () { window.removeEventListener('resize', onWindowResize, false); });
};

OrbitCamera.prototype.update = function (dt) {
    var t = this.inertiaFactor === 0 ? 1 : Math.min(dt / this.inertiaFactor, 1);
    this._distance = pc.math.lerp(this._distance, this._targetDistance, t);
    this._yaw = pc.math.lerp(this._yaw, this._targetYaw, t);
    this._pitch = pc.math.lerp(this._pitch, this._targetPitch, t);
    this._updatePosition();
};

OrbitCamera.prototype._updatePosition = function () {
    this.entity.setLocalPosition(0, 0, 0);
    this.entity.setLocalEulerAngles(this._pitch, this._yaw, 0);
    var position = this.entity.getPosition();
    position.copy(this.entity.forward);
    position.mulScalar(-this._distance);
    position.add(this.pivotPoint);
    // Clamp camera's Y position so it never goes below minY
    position.y = Math.max(position.y, this.minY);
    this.entity.setPosition(position);
};

OrbitCamera.prototype._removeInertia = function () {
    this._yaw = this._targetYaw;
    this._pitch = this._targetPitch;
    this._distance = this._targetDistance;
};

OrbitCamera.prototype._checkAspectRatio = function () {
    var height = this.app.graphicsDevice.height;
    var width = this.app.graphicsDevice.width;
    this.entity.camera.horizontalFov = (height > width);
};

OrbitCamera.prototype._buildAabb = function (entity) {
    var i, m, meshInstances = [];
    var renders = entity.findComponents('render');
    for (i = 0; i < renders.length; i++) {
        var render = renders[i];
        for (m = 0; m < render.meshInstances.length; m++) {
            meshInstances.push(render.meshInstances[m]);
        }
    }
    var models = entity.findComponents('model');
    for (i = 0; i < models.length; i++) {
        var model = models[i];
        for (m = 0; m < model.meshInstances.length; m++) {
            meshInstances.push(model.meshInstances[m]);
        }
    }
    var gsplats = entity.findComponents('gsplat');
    for (i = 0; i < gsplats.length; i++) {
        var gsplat = gsplats[i];
        var instance = gsplat.instance;
        if (instance?.meshInstance) {
            meshInstances.push(instance.meshInstance);
        }
    }
    for (i = 0; i < meshInstances.length; i++) {
        if (i === 0) {
            this._modelsAabb.copy(meshInstances[i].aabb);
        } else {
            this._modelsAabb.add(meshInstances[i].aabb);
        }
    }
};

OrbitCamera.prototype._calcYaw = function (quat) {
    var transformedForward = new pc.Vec3();
    quat.transformVector(pc.Vec3.FORWARD, transformedForward);
    return Math.atan2(-transformedForward.x, -transformedForward.z) * pc.math.RAD_TO_DEG;
};

OrbitCamera.prototype._clampDistance = function (distance) {
    if (this.distanceMax > 0) {
        return pc.math.clamp(distance, this.distanceMin, this.distanceMax);
    }
    return Math.max(distance, this.distanceMin);
};

OrbitCamera.prototype._clampPitchAngle = function (pitch) {
    return pc.math.clamp(pitch, this.pitchAngleMin, this.pitchAngleMax);
};

OrbitCamera.prototype._clampYawAngle = function (yaw) {
    return pc.math.clamp(yaw, -this.yawAngleMax, -this.yawAngleMin);
};

OrbitCamera.quatWithoutYaw = new pc.Quat();
OrbitCamera.yawOffset = new pc.Quat();

OrbitCamera.prototype._calcPitch = function (quat, yaw) {
    var quatWithoutYaw = OrbitCamera.quatWithoutYaw;
    var yawOffset = OrbitCamera.yawOffset;
    yawOffset.setFromEulerAngles(0, -yaw, 0);
    quatWithoutYaw.mul2(yawOffset, quat);
    var transformedForward = new pc.Vec3();
    quatWithoutYaw.transformVector(pc.Vec3.FORWARD, transformedForward);
    return Math.atan2(-transformedForward.y, -transformedForward.z) * pc.math.RAD_TO_DEG;
};

// ===================== Orbit Camera Input Mouse Script ========================
var OrbitCameraInputMouse = pc.createScript('orbitCameraInputMouse');
OrbitCameraInputMouse.attributes.add('orbitSensitivity', { type: 'number', default: 0.3, title: 'Orbit Sensitivity' });
OrbitCameraInputMouse.attributes.add('distanceSensitivity', { type: 'number', default: 0.4, title: 'Distance Sensitivity' });

OrbitCameraInputMouse.prototype.initialize = function () {
    this.orbitCamera = this.entity.script.orbitCamera;
    if (this.orbitCamera) {
        var self = this;
        var onMouseOut = function (e) { self.onMouseOut(e); };
        this.app.mouse.on(pc.EVENT_MOUSEDOWN, this.onMouseDown, this);
        this.app.mouse.on(pc.EVENT_MOUSEUP, this.onMouseUp, this);
        this.app.mouse.on(pc.EVENT_MOUSEMOVE, this.onMouseMove, this);
        this.app.mouse.on(pc.EVENT_MOUSEWHEEL, this.onMouseWheel, this);
        window.addEventListener('mouseout', onMouseOut, false);
        this.on('destroy', function () {
            this.app.mouse.off(pc.EVENT_MOUSEDOWN, this.onMouseDown, this);
            this.app.mouse.off(pc.EVENT_MOUSEUP, this.onMouseUp, this);
            this.app.mouse.off(pc.EVENT_MOUSEMOVE, this.onMouseMove, this);
            this.app.mouse.off(pc.EVENT_MOUSEWHEEL, this.onMouseWheel, this);
            window.removeEventListener('mouseout', onMouseOut, false);
        });
    }
    this.app.mouse.disableContextMenu();
    this.lookButtonDown = false;
    this.panButtonDown = false;
    this.lastPoint = new pc.Vec2();
};
OrbitCameraInputMouse.fromWorldPoint = new pc.Vec3();
OrbitCameraInputMouse.toWorldPoint = new pc.Vec3();
OrbitCameraInputMouse.worldDiff = new pc.Vec3();

OrbitCameraInputMouse.prototype.pan = function (screenPoint) {
    var fromWorldPoint = OrbitCameraInputMouse.fromWorldPoint;
    var toWorldPoint = OrbitCameraInputMouse.toWorldPoint;
    var worldDiff = OrbitCameraInputMouse.worldDiff;
    var camera = this.entity.camera;
    var distance = this.orbitCamera.distance;
    camera.screenToWorld(screenPoint.x, screenPoint.y, distance, fromWorldPoint);
    camera.screenToWorld(this.lastPoint.x, this.lastPoint.y, distance, toWorldPoint);
    worldDiff.sub2(toWorldPoint, fromWorldPoint);

    // Clamp so camera never goes below minY
    var proposedPivot = this.orbitCamera.pivotPoint.clone().add(worldDiff);
    var minY = this.orbitCamera.minY;
    var resultingY = this.orbitCamera.worldCameraYForPivot(proposedPivot);

    if (resultingY >= minY - 1e-4) {
        this.orbitCamera.pivotPoint.add(worldDiff);
    } else {
        // Only allow horizontal pan if it would help
        worldDiff.y = 0;
        proposedPivot = this.orbitCamera.pivotPoint.clone().add(worldDiff);
        resultingY = this.orbitCamera.worldCameraYForPivot(proposedPivot);
        if (resultingY >= minY - 1e-4) {
            this.orbitCamera.pivotPoint.add(worldDiff);
        }
        // Otherwise, suppress pan
    }
};

OrbitCameraInputMouse.prototype.onMouseDown = function (event) {
    switch (event.button) {
        case pc.MOUSEBUTTON_LEFT: this.panButtonDown = true; break;
        case pc.MOUSEBUTTON_MIDDLE:
        case pc.MOUSEBUTTON_RIGHT: this.lookButtonDown = true; break;
    }
};
OrbitCameraInputMouse.prototype.onMouseUp = function (event) {
    switch (event.button) {
        case pc.MOUSEBUTTON_LEFT: this.panButtonDown = false; break;
        case pc.MOUSEBUTTON_MIDDLE:
        case pc.MOUSEBUTTON_RIGHT: this.lookButtonDown = false; break;
    }
};
OrbitCameraInputMouse.prototype.onMouseMove = function (event) {
    if (this.lookButtonDown) {
        var sens = this.orbitSensitivity;
        var deltaPitch = event.dy * sens;
        var deltaYaw = event.dx * sens;

        var currPitch = this.orbitCamera.pitch;
        var currYaw = this.orbitCamera.yaw;
        var currDist = this.orbitCamera.distance;
        var currPivot = this.orbitCamera.pivotPoint.clone();

        var camQuat = new pc.Quat();
        camQuat.setFromEulerAngles(currPitch, currYaw, 0);
        var forward = new pc.Vec3();
        camQuat.transformVector(pc.Vec3.FORWARD, forward);
        var preY = currPivot.y + (-forward.y) * currDist;

        var proposedPitch = currPitch - deltaPitch;
        var testQuat = new pc.Quat();
        testQuat.setFromEulerAngles(proposedPitch, currYaw, 0);
        var testForward = new pc.Vec3();
        testQuat.transformVector(pc.Vec3.FORWARD, testForward);
        var proposedY = currPivot.y + (-testForward.y) * currDist;

        var minY = this.orbitCamera.minY;
        var wouldGoBelow = proposedY < minY - 1e-4;
        if (wouldGoBelow && (proposedY < preY)) {
            this.orbitCamera.yaw = currYaw - deltaYaw;
        } else {
            this.orbitCamera.pitch = proposedPitch;
            this.orbitCamera.yaw = currYaw - deltaYaw;
        }
    } else if (this.panButtonDown) {
        this.pan(new pc.Vec2(event.x, event.y));
    }
    this.lastPoint.set(event.x, event.y);
};

OrbitCameraInputMouse.prototype.onMouseWheel = function (event) {
    if (this.entity.camera.projection === pc.PROJECTION_PERSPECTIVE) {
        this.orbitCamera.distance -= event.wheelDelta * this.distanceSensitivity * (this.orbitCamera.distance * 0.1);
    } else {
        this.orbitCamera.orthoHeight -= event.wheelDelta * this.distanceSensitivity * (this.orbitCamera.orthoHeight * 0.1);
    }
    event.event.preventDefault();
};
OrbitCameraInputMouse.prototype.onMouseOut = function (event) {
    this.lookButtonDown = false;
    this.panButtonDown = false;
};

// =================== Orbit Camera Input Touch Script ========================
var OrbitCameraInputTouch = pc.createScript('orbitCameraInputTouch');
OrbitCameraInputTouch.attributes.add('orbitSensitivity', { type: 'number', default: 0.6, title: 'Orbit Sensitivity' });
OrbitCameraInputTouch.attributes.add('distanceSensitivity', { type: 'number', default: 0.5, title: 'Distance Sensitivity' });
OrbitCameraInputTouch.prototype.initialize = function () {
    this.orbitCamera = this.entity.script.orbitCamera;
    this.lastTouchPoint = new pc.Vec2();
    this.lastPinchMidPoint = new pc.Vec2();
    this.lastPinchDistance = 0;
    if (this.orbitCamera && this.app.touch) {
        this.app.touch.on(pc.EVENT_TOUCHSTART, this.onTouchStartEndCancel, this);
        this.app.touch.on(pc.EVENT_TOUCHEND, this.onTouchStartEndCancel, this);
        this.app.touch.on(pc.EVENT_TOUCHCANCEL, this.onTouchStartEndCancel, this);
        this.app.touch.on(pc.EVENT_TOUCHMOVE, this.onTouchMove, this);
        this.on('destroy', function () {
            this.app.touch.off(pc.EVENT_TOUCHSTART, this.onTouchStartEndCancel, this);
            this.app.touch.off(pc.EVENT_TOUCHEND, this.onTouchStartEndCancel, this);
            this.app.touch.off(pc.EVENT_TOUCHCANCEL, this.onTouchStartEndCancel, this);
            this.app.touch.off(pc.EVENT_TOUCHMOVE, this.onTouchMove, this);
        });
    }
};
OrbitCameraInputTouch.prototype.getPinchDistance = function (pointA, pointB) {
    var dx = pointA.x - pointB.x;
    var dy = pointA.y - pointB.y;
    return Math.sqrt((dx * dx) + (dy * dy));
};
OrbitCameraInputTouch.prototype.calcMidPoint = function (pointA, pointB, result) {
    result.set(pointB.x - pointA.x, pointB.y - pointA.y);
    result.mulScalar(0.5);
    result.x += pointA.x;
    result.y += pointA.y;
};
OrbitCameraInputTouch.prototype.onTouchStartEndCancel = function (event) {
    var touches = event.touches;
    if (touches.length === 1) {
        this.lastTouchPoint.set(touches[0].x, touches[0].y);
    } else if (touches.length === 2) {
        this.lastPinchDistance = this.getPinchDistance(touches[0], touches[1]);
        this.calcMidPoint(touches[0], touches[1], this.lastPinchMidPoint);
    }
};
OrbitCameraInputTouch.fromWorldPoint = new pc.Vec3();
OrbitCameraInputTouch.toWorldPoint = new pc.Vec3();
OrbitCameraInputTouch.worldDiff = new pc.Vec3();
OrbitCameraInputTouch.prototype.pan = function (midPoint) {
    var fromWorldPoint = OrbitCameraInputTouch.fromWorldPoint;
    var toWorldPoint = OrbitCameraInputTouch.toWorldPoint;
    var worldDiff = OrbitCameraInputTouch.worldDiff;
    var camera = this.entity.camera;
    var distance = this.orbitCamera.distance;
    camera.screenToWorld(midPoint.x, midPoint.y, distance, fromWorldPoint);
    camera.screenToWorld(this.lastPinchMidPoint.x, this.lastPinchMidPoint.y, distance, toWorldPoint);
    worldDiff.sub2(toWorldPoint, fromWorldPoint);

    var proposedPivot = this.orbitCamera.pivotPoint.clone().add(worldDiff);
    var minY = this.orbitCamera.minY;
    var resultingY = this.orbitCamera.worldCameraYForPivot(proposedPivot);

    if (resultingY >= minY - 1e-4) {
        this.orbitCamera.pivotPoint.add(worldDiff);
    } else {
        worldDiff.y = 0;
        proposedPivot = this.orbitCamera.pivotPoint.clone().add(worldDiff);
        resultingY = this.orbitCamera.worldCameraYForPivot(proposedPivot);
        if (resultingY >= minY - 1e-4) {
            this.orbitCamera.pivotPoint.add(worldDiff);
        }
    }
};

OrbitCameraInputTouch.pinchMidPoint = new pc.Vec2();

OrbitCameraInputTouch.prototype.onTouchMove = function (event) {
    var pinchMidPoint = OrbitCameraInputTouch.pinchMidPoint;
    var touches = event.touches;
    if (touches.length === 1) {
        var touch = touches[0];
        var sens = this.orbitSensitivity;
        var deltaPitch = (touch.y - this.lastTouchPoint.y) * sens;
        var deltaYaw = (touch.x - this.lastTouchPoint.x) * sens;

        var currPitch = this.orbitCamera.pitch;
        var currYaw = this.orbitCamera.yaw;
        var currDist = this.orbitCamera.distance;
        var currPivot = this.orbitCamera.pivotPoint.clone();

        var camQuat = new pc.Quat();
        camQuat.setFromEulerAngles(currPitch, currYaw, 0);
        var forward = new pc.Vec3();
        camQuat.transformVector(pc.Vec3.FORWARD, forward);
        var preY = currPivot.y + (-forward.y) * currDist;

        var proposedPitch = currPitch - deltaPitch;
        var testQuat = new pc.Quat();
        testQuat.setFromEulerAngles(proposedPitch, currYaw, 0);
        var testForward = new pc.Vec3();
        testQuat.transformVector(pc.Vec3.FORWARD, testForward);
        var proposedY = currPivot.y + (-testForward.y) * currDist;

        var minY = this.orbitCamera.minY;
        var wouldGoBelow = proposedY < minY - 1e-4;
        if (wouldGoBelow && (proposedY < preY)) {
            this.orbitCamera.yaw = currYaw - deltaYaw;
        } else {
            this.orbitCamera.pitch = proposedPitch;
            this.orbitCamera.yaw = currYaw - deltaYaw;
        }
        this.lastTouchPoint.set(touch.x, touch.y);
    } else if (touches.length === 2) {
        var currentPinchDistance = this.getPinchDistance(touches[0], touches[1]);
        var diffInPinchDistance = currentPinchDistance - this.lastPinchDistance;
        this.lastPinchDistance = currentPinchDistance;
        this.orbitCamera.distance -= (diffInPinchDistance * this.distanceSensitivity * 0.1) * (this.orbitCamera.distance * 0.1);
        this.calcMidPoint(touches[0], touches[1], pinchMidPoint);
        this.pan(pinchMidPoint);
        this.lastPinchMidPoint.copy(pinchMidPoint);
    }
};