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News:

An update to Anim8or, v1.00b, is available with a few bug fixes. Get your copy HERE. See the "ReadMe" file for details.

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 91 
 on: September 03, 2018, 04:24:35 pm 
Started by SomariHater - Last post by Steve
The convention that Anim8or uses is:

Looking down an axis in the negative direction, a positive rotation turns clockwise. Some applications do the opposite. Here is a simple axis model and a drawing:


 92 
 on: September 03, 2018, 02:33:08 pm 
Started by SomariHater - Last post by SomariHater
Yes. I read that, and I've read similar posts like this one: http://www.anim8or.com/smf/index.php/topic,4861.msg35328.html#msg35328. However,  it seems like the writeup doesn't answer this question, and an answer was never determined in that other post.

The angles in figure mode match the writeup and match what I expect for euler angles. For instance, if I increase the "yaw" or angle about the y axis in figure mode, when viewed from the top, the object spins clockwise (which is consistent with the "simple Euler rotations" in the writeup).

However, sequence mode isn't behaving like I expect. For instance, if I increase the angle about the y axis in sequence mode, when viewed from the top, the figure spins counter-clockwise.

In figure mode, if I apply a Y angle of 45 degrees, and a Z angle of 45 degrees, when viewed from the top, the object tilts to the bottom right.

In sequence mode, if I apply a Y angle of 45 degrees, and a Z angle of 45 degrees, when viewed from the top, the object tilts left with a twist.

I'm probably making a stupid mistake somewhere, but the angles don't seem to mean the same thing in figure and sequence mode. I think if the writeup showed how the axes moved in sequence mode and the order of the rotations, then I could understand better.

 93 
 on: September 03, 2018, 07:35:58 am 
Started by SomariHater - Last post by Raxx
Have you looked at Steve's writeup here? http://www.anim8or.com/learn/technical/quaternions_and_anim8or/quaternions_and_anim8or.htm This topic has also been brought up a lot in the forums, you may find the answer to what you're looking for in the search results here.

 94 
 on: September 03, 2018, 03:00:28 am 
Started by SomariHater - Last post by SomariHater
I found LibAn8 (https://sourceforge.net/p/liban8/code/HEAD/tree/). It looks like it translates a "Joint Angles (XYZ)" of 0, 45, 45 into the quaternion (0.14645 0.35355 0.35355 0.85355). That is the same as how Anim8or translates a "Orientation (PYR)" of 0, 45, 45 except that the Y and Z positions are positive instead of negative.

That means, LibAn8 claims that an "Orientation (PYR)" of 0, 45, 45 is equivalent to a "Joint Angles (XYZ)" of 0, -45, -45 even though they give different  results in Anim8or. I'm still confused.

 95 
 on: September 02, 2018, 09:58:45 pm 
Started by SomariHater - Last post by SomariHater
I'm trying to figure out how to interpret the joint angles in the sequence section of an8 files. If someone could help me convert the joint angle into a quaternion or a rotation matrix or even XYZ Euler angles, that would be great. (It is okay to assume every keyframe has "X", "Y", and "Z" values for simplicity. I can figure out the interpolation. Also, assume there is just one bone besides the root bone. I can figure out the hierarchy.)

I am trying to reverse engineer it, but I'm getting lost (the an8 spec doesn't say how to interpret the value as far as I can tell). When I set the "Orientation (PYR)" of a bone in figure mode to 0, 45, 45, Anim8or saves a bone orientation quaternion of (0.14645 -0.35355 -0.35355 0.85355) into the figure section of the file. This is what I expect for XYZ Euler angles.

However, if the "Orientation (PYR)" is 0, 0, 0 in figure mode, and I set the "Joint Angles (XYZ)" of a bone in sequence mode to 0, 45, 45, Anim8or displays a very different rotation than figure mode. By manually rotating the bone in sequence mode, I was able to figure out that a "Joint Angle (XYZ)" of 38.5, -61.4, -24.8 produces a similar result to a "Orientation (PYR)" of 0, 45, 45. I attached some pictures to show what I mean.

So, if anyone could help me decode what "Joint Angle (XYZ)" means, that would be awesome. Thanks. Also, if you need more information let me know.

 96 
 on: August 31, 2018, 08:13:47 pm 
Started by Steve - Last post by Steve
Yeah, I should make that more obvious somehow.

 97 
 on: August 31, 2018, 08:12:48 pm 
Started by Steve - Last post by Steve
It could be worse - at least I don't have a boss bugging me to work harder :)  It's going a bit faster the second time. I have the multi-thread code finished and bunch of small things, and I'm working on the new bone editing now.

 98 
 on: August 31, 2018, 05:04:23 pm 
Started by Steve - Last post by captaindrewi
i have been grumbling to myself for months about the new track ball system and have only just realised i could change it via 'options'..... :-\.dull as dish water me.
But having both seems great. 8)

 99 
 on: August 31, 2018, 04:48:27 pm 
Started by Steve - Last post by captaindrewi
Just heard the news....amazed you are so calm about it.

 100 
 on: August 28, 2018, 05:02:54 am 
Started by Steve - Last post by chuft-captain
BTW Steve,

Sent you a PM / Email about an issue we discussed a few months ago. (No panic obviously  8) )

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