44 lines
1.9 KiB
C#
44 lines
1.9 KiB
C#
using UnityEngine;
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namespace RebootKit.Engine.Foundation {
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public static class MathUtility {
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// Spring math
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// Source: https://allenchou.net/2015/04/game-math-precise-control-over-numeric-springing/
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public static void Spring(ref float current,
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ref float velocity,
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float target,
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float halfLife,
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float frequency,
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float timeStep) {
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float dampingRatio = -Mathf.Log(0.5f) / (frequency * halfLife);
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float f = 1.0f + 2.0f * timeStep * dampingRatio * frequency;
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float oo = frequency * frequency;
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float hoo = timeStep * oo;
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float hhoo = timeStep * hoo;
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float detInv = 1.0f / (f + hhoo);
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float detX = f * current + timeStep * velocity + hhoo * target;
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float detV = velocity + hoo * (target - current);
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current = detX * detInv;
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velocity = detV * detInv;
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}
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public static void Spring(ref Vector3 current,
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ref Vector3 velocity,
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Vector3 target,
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float halfLife,
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float frequency,
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float timeStep) {
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float dampingRatio = -Mathf.Log(0.5f) / (frequency * halfLife);
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float f = 1.0f + 2.0f * timeStep * dampingRatio * frequency;
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float oo = frequency * frequency;
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float hoo = timeStep * oo;
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float hhoo = timeStep * hoo;
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float detInv = 1.0f / (f + hhoo);
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Vector3 detX = f * current + timeStep * velocity + hhoo * target;
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Vector3 detV = velocity + hoo * (target - current);
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current = detX * detInv;
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velocity = detV * detInv;
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}
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}
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} |