Stream: brlcad

Topic: tra


view this post on Zulip starseeker (Jun 10 2021 at 22:30):

Hey @Sean , are these the expected results for the "tra" command in MGED? I'm seeing this as far back as 7.28.2...

mged> center 0 0 0
mged> ae 90 0
mged> center
0 0 0
mged> tra 0 0 50
mged> center
0 50 -0
mged> center 0 0 0
mged> tra 0 50 0
mged> center
0 0 50
mged>

I may be thinking about tra wrong, but it's surprising to me that the y value changes when I specify a z delta and vice versa...

view this post on Zulip Sean (Jun 11 2021 at 03:36):

@starseeker Yes, that is expected results.

view this post on Zulip Sean (Jun 11 2021 at 03:36):

It's awkward because of the specific azel choice and what you think tra is doing isn't what it's doing

view this post on Zulip Sean (Jun 11 2021 at 03:37):

in view edit mode, tra manipulates the viewport

view this post on Zulip Sean (Jun 11 2021 at 03:37):

with X being the horizontal, Y being the vertical

view this post on Zulip Sean (Jun 11 2021 at 03:38):

Z is consequently in and out of the screen, which does nothing visible to an orthogonal view (you'd notice it move in perspective)

view this post on Zulip Sean (Jun 11 2021 at 03:40):

so tra 0 0 50 moves the viewport back 50 units ... and moving back along an ae 90 0 side view happens to be the Y axis in model space

view this post on Zulip Sean (Jun 11 2021 at 03:41):

it should make a lot more sense if you just think of it as "pan X Y [ignore]" to pan the viewport horizontally and vertically

view this post on Zulip Sean (Jun 11 2021 at 03:43):

then it should make sense what the Z value does, especially if you set perspective 70 or something

view this post on Zulip starseeker (Jun 11 2021 at 12:24):

/me nods. Phew, thanks - saw that in qged and had visions of having introduced some obscure low level bug somewhere...


Last updated: Oct 09 2024 at 00:44 UTC