Which Axis is north?

Using Get Control Rotation YAW, are these correct?

0.0 - East
90 - South
180 - West
270 - North

That would make World +X East, -X West. -Y North, +Y South?

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it can be whatever you want. Its not built into the engine. Scale isn’t built into the engine, you can work at almost any scale you want. There isn’t a world, so how could there be directions?

Is there something that you were referencing to know directions?

I went with -Y as North because I was using Character Yaw as my baseline

Please note that skeletal meshes coming from Maya, for example the default Blue Guy, has a 90 degree offset and faces +Y by default until you correct it in the component transform. The character class should have an arrow showing you forward, which should be +X.

I suggest not trying to use any other direction as the built in Blueprint library expects +X as forward vector, +Y as side vector and +Z as up vector (as previously mentioned).

For simplicities sake I can see why you would use +X as north, 0.0 degrees Yaw is on the +X axis. In the real world that means East but I guess in the end it doesn’t really matter much, this question was so I could set up a compass using my characters yaw rotation, which I have already done. It’s easy for me to change the letters , I already have the range values for each direction, all they do is set a string variable to whatever letter I assign them

That should be perfectly fine. I didn’t think you literally meant north, as in using a compass. :smiley:

Funny, I was looking for an answer to this to name meshes and reference docs, but it just hit me that it is better to just go with ExteriorWall+X :slight_smile: Stupidity attack

YES
Importing a real point cloud with correct coordinates result:
+X East, -X West. -Y North, +Y South

I think this is important for when you are simulating geolocated sunlight. Did you work out which axis is North?

Which axis is “north” depends entirely on your code and assumptions and input data, not on the engine.

If you have built a model of the world that puts East along X and North along -Y, then that’s what your sunlight shader and general logic should assume. (Also note: Unreal Engine uses left-handed interpretation of coordinates, like a compass, not right-handed, like you’d typically draw a unit circle!)

Another way to think about this: “When a character controller has a yaw of 0, and moves straight forward, which axis does it move along?” (IIRC, It moves along the X axis.) Now, asking yourself “Which direction do I want a character controller to move when it has 0 yaw?” will answer “what cardinal direction should I make the X axis correspond to?”

This whole subject makes 0 sense. In all possible sense.

NORTH is a human construct derived from the earth’s natural magnetic field.
So much so that we have True North and Magnetic North just to confuse navigational matter further.

In an environment that you define, how can we tell you what You made your cardinal directions out to be?

You can adjust the rotation of the sun/sky actor to match taste too, so it wouldn’t make much sense even when using cookie cutter pieces…