AstralTransRocketries/MCGalaxy
1
0
Fork 0
mirror of https://github.com/ClassiCube/MCGalaxy.git synced 2025-09-22 12:05:51 -04:00
Code Issues Packages Projects Releases Wiki Activity

Add a generic GetYawPitch method.

Browse Source
This commit is contained in:
UnknownShadow200 2016-08-29 13:05:25 +10:00
parent 96ed7139ff
commit 7bed4d7963
1 changed files with 33 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
util/Math/DirUtils.cs
View File

@ -82,5 +82,38 @@ namespace MCGalaxy {
double z = -Math.Cos(yaw * packed2Rad); // e.g. 128 -> PI, result should be 1
return new Vec3F32((float)x, (float)y, (float)z);
}
public static Vec3F32 GetAdjDirVector(byte yaw, byte pitch) {
const double packed2Rad = (2 * Math.PI) / 256.0;
double x = Math.Sin(yaw * packed2Rad) * Math.Cos(pitch * packed2Rad);
double y = -Math.Sin(pitch * packed2Rad);
double z = -Math.Cos(yaw * packed2Rad) * Math.Cos(pitch * packed2Rad);
return new Vec3F32((float)x, (float)y, (float)z);
}
public static void GetYawPitch(Vec3F32 dir, out byte yaw, out byte pitch) {
// y = -sin(pitch) -> pitch = arcsin(-y)
// x = sin(yaw) * cos(pitch) -> yaw = arcsin(x/cos(pitch))
// z = -cos(yaw) * cos(pitch) -> yaw = arccos(-z/cos(pitch))
const double rad2Packed = 256.0 / (2 * Math.PI);
// NOTE: This conversion method **does** lose information
// a) If pitch is 0, yaw cannot be properly recalculated
// b) Pitch will always be from 0-64 or 192-256, therefore flipped heads lost
// However since we have X/Z, this problem does not occur for yaw,
// as we can use both values to determine which side of unit circle yaw is in
// c) Resulting yaw/pitch may be 1 or 2 values off due to rounding
double pitchRad = Math.Asin(-dir.Y);
double cosPitch = Math.Cos(pitchRad);
double yawRad = Math.Asin(dir.X / cosPitch);
yaw = (byte)(yawRad * rad2Packed);
pitch = (byte)(pitchRad * rad2Packed);
// Other side of unit circle
if (dir.Z > 0) yaw = (byte)(128 - yaw);
// Almost exactly +X or -X
if (dir.Z >= 0 && dir.Z < +0.0000001) yaw = 192;
if (dir.Z <= 0 && dir.Z > -0.0000001) yaw = 64;
}
}
}