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Full Version: understanding brush dynamics (angle jitter)
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I want an arrow that wiggles a little bit, as i drag the brush along.

Im not sure i understand the dynamics curves fully....

So on the left side i have 'Angle' and on the right side 'Randomness', right ?

But when i turn up 'Angle', the arrows wiggle to the right and when i restrict 'Randomness', they wiggle to the left.

What is the logic behind this ? 

[attachment=1110]
Each little square represents 45 degrees (360/8)

First example, angle varies from 315 to 360

Second, angle varies from 0 to 45

Third, angle varies from 135 to 225

If you want arrows as per third example, but upright, then start with an upside down arrow.
"Random"  goes from 0.0 tà 1.00 (or read it as "min" to "max"). The Angle scale goes from min to max too, that is, 0 to 360°. Catch: the middle position is 180°, so the brush is upside-down!  Obviously the angle is the "trignometric" angle, which is counter-clockwise. So, top to bottom:
  • The angle is constrained to 340-360°, so the same as -20°-0° CCW, which is 0°-20° clock-wise.
  • The angle is constrained to 0°-20° CCW, so the same as -20°-0° clock-wise.
  • The angle is constrained to 170-190° so more or less upside-down.

So yes, having the brush wiggle a bit around its "upright" position requires a very contrived curve, and its better to use an upside down brush:

[attachment=1112]

[attachment=1111]

Changing the angle range from -180° to +180° has already been suggested.
A-ha !

Once you understand that each square represents an eighth its getting easier !
Is there a specific design reason for eight squares, instead of ten (which would be easier to calculate) ?

Fine tuning the wiggle seems very difficult....what if i want it at half a square...when i do that, a bit of the graph is off the diagram.....

[attachment=1113]


Also, what does this type of curve mean ?

[attachment=1114]
(12-14-2017, 12:01 PM)Espermaschine Wrote: [ -> ]Also, what does this type of curve mean ?

Left half of curve:
50% of your arrows will be random 0 to 360

Right half:
This only has 360 degrees. Remaining 50% of arrows will be upright.
some aspects of these curves blow my mind a bit...  Confused

EDIT:
a-ha ! i get it - the curve is only applied to half of the diagram