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July 21, 2015 15:07
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This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,169 @@ using System; using UnityEngine; namespace RamjetAnvil.Networking { public static class Compression { public static class Rotation { private const float Minimum = -1.0f / 1.414214f; // note: 1.0f / sqrt(2) private const float Maximum = +1.0f / 1.414214f; public static uint Compress(Quaternion rotation) { float absX = Mathf.Abs(rotation.x), absY = Mathf.Abs(rotation.y), absZ = Mathf.Abs(rotation.z), absW = Mathf.Abs(rotation.w); var largestComponent = new LargestComponent(ComponentType.X, absX); if (absY > largestComponent.Value) { largestComponent.Value = absY; largestComponent.ComponentType = ComponentType.Y; } if (absZ > largestComponent.Value) { largestComponent.Value = absZ; largestComponent.ComponentType = ComponentType.Z; } if (absW > largestComponent.Value) { largestComponent.Value = absW; largestComponent.ComponentType = ComponentType.W; } float a, b, c; switch (largestComponent.ComponentType) { case ComponentType.X: if (rotation.x >= 0) { a = rotation.y; b = rotation.z; c = rotation.w; } else { a = -rotation.y; b = -rotation.z; c = -rotation.w; } break; case ComponentType.Y: if (rotation.y >= 0) { a = rotation.x; b = rotation.z; c = rotation.w; } else { a = -rotation.x; b = -rotation.z; c = -rotation.w; } break; case ComponentType.Z: if (rotation.z >= 0) { a = rotation.x; b = rotation.y; c = rotation.w; } else { a = -rotation.x; b = -rotation.y; c = -rotation.w; } break; case ComponentType.W: if (rotation.w >= 0) { a = rotation.x; b = rotation.y; c = rotation.z; } else { a = -rotation.x; b = -rotation.y; c = -rotation.z; } break; default: // Should never happen! throw new ArgumentOutOfRangeException("Unknown rotation component type: " + largestComponent.ComponentType); } float normalizedA = (a - Minimum) / (Maximum - Minimum), normalizedB = (b - Minimum) / (Maximum - Minimum), normalizedC = (c - Minimum) / (Maximum - Minimum); uint integerA = (uint) Mathf.FloorToInt(normalizedA * 1024.0f + 0.5f), integerB = (uint) Mathf.FloorToInt(normalizedB * 1024.0f + 0.5f), integerC = (uint) Mathf.FloorToInt(normalizedC * 1024.0f + 0.5f); return (((uint) largestComponent.ComponentType) << 30) | (integerA << 20) | (integerB << 10) | integerC; } public static Quaternion Decompress(uint compressedRotation) { var largestComponentType = (ComponentType) (compressedRotation >> 30); uint integerA = (compressedRotation >> 20) & ((1 << 10) - 1), integerB = (compressedRotation >> 10) & ((1 << 10) - 1), integerC = compressedRotation & ((1 << 10) - 1); float a = integerA / 1024.0f * (Maximum - Minimum) + Minimum, b = integerB / 1024.0f * (Maximum - Minimum) + Minimum, c = integerC / 1024.0f * (Maximum - Minimum) + Minimum; Quaternion rotation; switch (largestComponentType) { case ComponentType.X: // (?) y z w rotation.y = a; rotation.z = b; rotation.w = c; rotation.x = Mathf.Sqrt(1 - rotation.y * rotation.y - rotation.z * rotation.z - rotation.w * rotation.w); break; case ComponentType.Y: // x (?) z w rotation.x = a; rotation.z = b; rotation.w = c; rotation.y = Mathf.Sqrt(1 - rotation.x * rotation.x - rotation.z * rotation.z - rotation.w * rotation.w); break; case ComponentType.Z: // x y (?) w rotation.x = a; rotation.y = b; rotation.w = c; rotation.z = Mathf.Sqrt(1 - rotation.x * rotation.x - rotation.y * rotation.y - rotation.w * rotation.w); break; case ComponentType.W: // x y z (?) rotation.x = a; rotation.y = b; rotation.z = c; rotation.w = Mathf.Sqrt(1 - rotation.x * rotation.x - rotation.y * rotation.y - rotation.z * rotation.z); break; default: // Should never happen! throw new ArgumentOutOfRangeException("Unknown rotation component type: " + largestComponentType); } return rotation; } private enum ComponentType : uint { X = 0, Y = 1, Z = 2, W = 3 } private struct LargestComponent { public ComponentType ComponentType; public float Value; public LargestComponent(ComponentType componentType, float value) { ComponentType = componentType; Value = value; } } } } }