I'm trying to create bone animation programatically which will be used for interpolation between two animations. My code: var bone = skeleton.bones[0];var bone_animation = bone.animations[0];var current_frame = Math.round(bone_animation.currentFrame);if(!current_frame) current_frame = 0;var animationArm = new BABYLON.Animation("myAnimation", "_matrix", 30, BABYLON.Animation.ANIMATIONTYPE_MATRIX);animationArm.setKeys([ {frame: 0, value: bone_animation._keys[current_frame].value}, {frame: 30