XFile Creation and XFileClasses Effects

[Fyron]

According to the mod doc, Starting Rotate and Starting Scale are in percents.

[MasterChiToes]

For the rotations, percents still leave it as 50% = 180 degrees, 25% = 90 degrees, etc...

I don't have a problem with it... it is just a little odd.

[Fyron]

I am confused about how the axes are arranged in regards to XFile_Classes, particularly for stellar objects. This is defined for every planet in XFileClasses_Stellar.txt:

Starting Rotate X := 50
Starting Rotate Y := 0
Starting Rotate Z := 25
...
Continual Rotation Vector X := 0
Continual Rotation Vector Y := 0
Continual Rotation Vector Z := 25
Continual Rotation Speed := 0.0001

The Continual Rotation seems to make sense, assuming the Z axis goes through the top and bottom of the planet, perpendicular to the system hex grid. Rotating around this axis should logically rotate the planet from left to right, along the system hex grid. However, the Starting Rotate Z value makes no sense... If I set it to 0, planets start out on their side, as in the attached screenshot (you can see the polar ice cap coming up on the left for the selected hydrogen planet; should be at the top with any value of Starting Rotate Z?) . Starting Rotate Z seems to be rotating along a different axis entirely; seemingly the Y axis. Shouldn't a non-zero value for Starting Rotate Z rotate the planet around the axis going through the top and bottom of the planet, perpendicular to the system hex grid? Am I misunderstanding the geometry of the SE5 engine, or is something screwy going on here?

[MasterChiToes]

The Docs say:
The percent rotation around the X plane.
The percent rotation around the Y plane.
The percent rotation around the Z plane.

However, each plane is 2D. So, this means:
The percent rotation around the XZ plane.
The percent rotation around the XY plane.
The percent rotation around the YZ plane.

(That is based on an X-plane of 50 (%) flipping the planet upside down.)

The unmodified initial orientation of planet has poles on Y axis (north being down) with the 'front' of the planet facing out (of the screen).

Looking into the screen on the motion:
Z CCW (from the top) with axis in-out (normal) of map.
Y (right to left) with axis bottom-top of map.
X (down to up) with axis left-right of map.

Looking at the starting rotations:
-- - North-South along Y (south up) front Z- (facing out)
25 Z North-South along Z (south out) Front Y- (facing down)
25 Y North-South along X (south right) front Z- (facing out)
25 X North-South along Y (south up) front X- (facing left)

******** conclusions *******
The axial motion:
The Z-pole's positive rotation is clockwise (from below the map, Z+).
The X-pole's positive rotation is clockwise (from the right of the map, X+)
The Y pole's positive rotation is clockwise (from the top of the map, Y+)

Initial orientations (Starting Rotate):
X rotates the object X+ toward Z- (right of screen towards you) or clockwise about the Y axis.
Y rotates the object Y+ toward X+ (top of screen towards right of screen) or counterclockwise about the Z axis.
Z rotates the object Y+ toward Z- (top of screen towards you) or counterclockwise about the X axis.

[Fyron]

So... is this how the axes are oriented? The black circle is on the plane of the system hex grid (the XZ plane).



I'm just trying to figure out how to make planets have a randomized starting rotation, in the same direction as the continual rotation vector. The Starting Rotate and Continual Rotation Vector fields seem to be referring to entirely different types of rotations, around different axes... its all very confusing.

[MasterChiToes]

You have Y and Z reversed. The hex grid is on the XY Plane... so change +Z to +Y, -Y to -Z, etc.

The Starting Rotate is not motion, just the initial fixed planetary orientation.
The three Continual Rotation vectors are the trick... the three vectors have to added in the proper amounts to prevent wobble and precession.

I am currently working on a cheat sheet for the vector addition... trying to get the Y tilts right now.

[Fyron]

MasterChiToes said:
"The Starting Rotate is not motion, just the initial fixed planetary orientation."

Never said it was motion.. I can now confirm that Starting Rotate Y and Continual Rotation Vector Z are in the same direction. Setting a non-zero value for Starting Rotate Y rotates the planet around the axis normal to the system hex grid, same as having a Continual Rotation Vector with only Z portions. Why Aaron coded things this way is beyond me...

=0=

So, the coordinate system should look like this then?

[MasterChiToes]

*tilt * |*spin * |+spin z
-------------------------------------
+tilt x |-tilt x |ARCSIN(1-SIN(tilt))
-tilt x |-tilt x | ""
-tilt z |+tilt y | ""
+tilt z |-tilt y | ""

example (from earlier post):
tilt = 3 (game units - not degrees or radians)
then 3 gets added or subtracted to Start Rotate X or Z
then the appropriate x or y spin become +/- 3
spin z = 15.1 (game units - not degrees or radians)

[MasterChiToes]

Right, those are the coordinates directions... so if you go to the overhead view of the system map, then my earlier post will make sense.

There is an error in my chart above, and I can't seem to edit it... the first row second column is +tilt x (not minus)

[MasterChiToes]