Squash & Stretch — Mass is conserved. When something compresses, it must bulge. A bouncing ball flattens on impact because its volume has to go somewhere.
Timing — Heavy = slow to start, slow to stop. Light = quick reactions. A truck and a bicycle brake very differently.
Slow In & Slow Out — Nothing starts or stops instantly. Acceleration and deceleration are the fingerprints of mass.
Arcs — Gravity curves everything. Even a punch follows a pendulum path from the shoulder. Straight lines feel robotic.
Secondary Action — When the main mass moves, attached masses follow with delay. Hair, clothing, jowls—they're all passengers on the physics train.
Follow Through & Overlapping Action — Different masses have different momentum. A character stops, but their belly keeps going. This is inertia made visible.
Anticipation — Force requires windup. You can't push without first pulling back. Show the gathering of energy before release.
Exaggeration — Push physics past reality to feel more real. A heavy landing needs more squash than actual physics would produce.
Staging — Position elements so physical relationships read clearly. The audience must understand spatial cause and effect.
Straight Ahead & Pose to Pose — Use straight ahead for chaotic physics (explosions, water). Use pose to pose for controlled physics (a character lifting something).
Solid Drawing — Volume must remain consistent. A character can't lose mass between frames without the audience noticing something is wrong.
Appeal — Even physics follows design. Decide if your world has cartoon physics or realistic physics, then be consistent.
Squash & Stretch — 质量守恒。当物体受到挤压时，必然会产生凸起。弹跳的球在撞击地面时会变扁，因为它的体积必须有去处。
Timing — 重物启动慢、停止也慢；轻物反应迅速。卡车和自行车的制动效果截然不同。
Slow In & Slow Out — 没有任何物体会瞬间启动或停止。加速与减速是质量的直观体现。
Arcs — 重力让所有运动轨迹都呈曲线。就连出拳也是从肩膀开始的钟摆式路径。直线运动看起来会很机械。
Secondary Action — 当主体运动时，附着在其上的物体会滞后跟随。头发、衣物、下巴赘肉——它们都是物理规律的“乘客”。
Follow Through & Overlapping Action — 不同质量的物体具有不同的动量。角色停下脚步，但肚子还会继续向前。这就是可见的惯性。
Anticipation — 施力需要蓄力。你无法不先向后拉就向前推。要在释放能量前展示能量的积聚过程。
Exaggeration — 突破现实物理限制，让效果更具真实感。重物落地时的挤压程度要比实际物理规律中的更明显。
Staging — 合理布置元素，让物理关系清晰可辨。观众必须能理解空间上的因果关系。
Straight Ahead & Pose to Pose — 混乱的物理效果（如爆炸、水流）适合用逐帧动画法；可控的物理效果（如角色举起重物）适合用关键帧动画法。
Solid Drawing — 体积必须保持一致。角色不能在帧与帧之间凭空失去质量，否则观众会察觉到违和感。
Appeal — 就连物理规律也要遵循设计风格。先确定你的世界是采用卡通物理还是写实物理，然后保持风格一致。