A views/baseplane mess

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Fat-Zer
Posts: 176
Joined: Thu Oct 30, 2014 10:38 pm

A views/baseplane mess

Post by Fat-Zer »

I couldn't decided where to start discussion about it here or on the Open discussion forum branch, but decided to discuss it here first because IMHO it must be settled up before the PartDesign workflow merge...

The issue is that XZ baseplane is reversed, it's normal directed in the negative Y direction, here is a demo:
Place a sketch on each plane and extrude
axis_assembly.png
axis_assembly.png (147.47 KiB) Viewed 1987 times
axis_assembly.fcstd
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Notice the direction of the coordinates in the right bottom angle, and that Y direction is reversed...
It's yet an easy to fix part...

The more complicated issue is that the current behavior follows the current 3d views: the front view is now actually a rear view (from the back side of XZ rather from the Tip of Y axis).

Also note some related discussion here: viewtopic.php?f=8&t=11911

So I propose to change the three main views so it would be:
  • Front view (from the tip of Y axis, current rear view)
  • Top view (as is, may be rotated along Z)
  • Left View (current right view)
Generally IMO this change should go straight to the master, but I'm afraid there will be some problems/misunderstanding from there, so I hope on some support from the assembly project participants...
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tanderson69
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Re: A views/baseplane mess

Post by tanderson69 »

Fat-Zer wrote:So I propose to change the three main views so it would be:
  • Front view (from the tip of Y axis, current rear view)
  • Top view (as is, may be rotated along Z)
  • Left View (current right view)
I have a feeling changing the views won't go over well. I haven't necessarily used a lot of cad systems, but I have never seen view definitions different from what freecad currently has. Hopefully others will chime in on their experiences. I would guess more people would be accepting of the xz plane plane being rotated 180 degrees around the absolute x axis.
ickby
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Re: A views/baseplane mess

Post by ickby »

The issue is that XZ baseplane is reversed, it's normal directed in the negative Y direction
Indeed, I never noiced that but it is wrong, well spotted! I'm clearly for chaning that one.
The more complicated issue is that the current behavior follows the current 3d views: the front view is now actually a rear view (from the back side of XZ rather from the Tip of Y axis).

Also note some related discussion here: viewtopic.php?f=8&t=11911

So I propose to change the three main views so it would be:
Front view (from the tip of Y axis, current rear view)
Top view (as is, may be rotated along Z)
Left View (current right view)
Hm, I did not really follow the view discussion, but from what I remember wasn't it a convention problem, different countries use different views? I think the most important thing is to allign the axis/planes of PartDesign with the axis cross in the corner. After that things like top/bottom/left/right are pure definition. I mean I see your point, but if we simply reverse it in the front view the x-axis would point to the left which is also pretty strange. The other way would be having Z going downwards, also not intuitive. IMHO it is more important to have X where it is in any graph as from this one can easily derive the different definitions of "front" etc.
Generally IMO this change should go straight to the master, but I'm afraid there will be some problems/misunderstanding from there, so I hope on some support from the assembly project participants..
I'm rather indifferent with this issue. And as there already is a discussion I would be ok with anything that comes out there, and I respect the result of that discussion. I just don't know what the conventions are in the other systems, I did not use anything next to solid works. So I think you should put in your weight in the ongoing discussion and try to convince the guys of your proposal.
galou_breizh
Posts: 436
Joined: Wed Sep 15, 2010 9:38 am

Re: A views/baseplane mess

Post by galou_breizh »

I think this subject is important, it's a pity it didn't get more attention. So I try to wake it up a little.

This not normal that an extrusion with a positive value from a sketch in the XZ plane is toward the positive Z axis (similarly an extrusion with the YZ plane is toward the positive X axis), whereas an extrusion with a positive value from a sketch in the XZ plane is toward the negative Y axis.

Maybe this could be solved by naming the plane perpendicular to the y-axis the ZX plane (as opposed to XZ plane).

Such a change (I mean to correct the direction of extrusion for the ZX plane) could bring problems with tutorials written before it but it is important to remove any illogical behavior. Is there a risk to break file compatibility here?
Fat-Zer
Posts: 176
Joined: Thu Oct 30, 2014 10:38 pm

Re: A views/baseplane mess

Post by Fat-Zer »

I've already fixed that for Origin's planes in my branch if you wonder... I'm unsure now if we should to do that for non-PartDesign sketches, but it will be a single line fix and can be discussed later...
galou_breizh wrote:Is there a risk to break file compatibility here?
File designed in current assembly branch won't be compatible (they don't supposed to be anyway). Files designed in master and non-PartDesign sketches shouldn't have any compatibility issues because Sketches without support have correct Placement...
galou_breizh wrote:Such a change (I mean to correct the direction of extrusion for the ZX plane) could bring problems with tutorials written before it
I believe when we will merge the new PartDesign workflow to the master nearly all PartDesign tutorials written before will be obsolete anyway, so that's not really a big deal ... ;)

But I still barely see how we can avoid confusion from the user and keep things consistent here... May be several standard views preset may be available...
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