Orbital Movement

• IcemanBo

Joined:
Sep 6, 2013
Messages:
6,236
Resources:
22
Maps:
3
Spells:
11
Template:
1
Tutorials:
4
JASS:
3
Resources:
22
Orbital Movement

There is an angle phi that is defined to rotate around z-axis [local system]. When it makes 360°, it will result in one complete rotation. It should be permanently increasing/decreasing, to simulate the motion.

The motion curve is described by 3 angles:
• alpha = yaw = rotation around x-axis [global system]
• beta = pitch = rotation around y-axis [global system]
• gamma = roll = rotation around z-axis [global system]
Difference between global and local coordination system
Global:

Global system is the world's normal axis system. It is constant, so x,y,z directions are always the same.

Local:

In this system the local system describes a 2D simple circle on its x-y-plane, meaning the z-coordinate is always 0.

Final Rotation + shift:

The final rotation is obtained by rotating the circle's local coordinate system around the global coordinate system. The shift from global origin is described by defined x/y/z center-coordinates.

... in this system the actual axis rotations can be described by 2 things:
• Amplitude:
Describes the axis rotation, between 0° and 360°.
Technically, with only defining amplitudes you already can get all possible points on the sphere.

• Frequency Factor:
The frequency factor will result in pendeling the respective axis rotation between amplitude values.
Its actual value will always be somewhere from amplitude to -amplitude.
• Factor = 0 → amplitude/axis rotation is constant
• Factor = 1 → amplitude/axis rotation equals phi_speed
• 0 < Factor < 1 → slower curves (with coming closer to 0 it gets slower)
• 1 < Factor → faster curves
So the factor only describes how fast the actual angle rotation goes between the amplitudes.

Example:
We make alpha_amplitude 50° and make frequency factor 2.
Now the alpha rotation (x-axis) will go between 50° and -50°, back and forth, with factor 2, leading in 2x speed of a normal sinus curve.

File size:
51.2 KB
Views:
141
File size:
55.8 KB
Views:
9