The result of the push pull would in my mind depend on the geometry / face it was derived from, like a flat surface makes a perpendicular extrusion or indentation, a curved however would make a perpendicular extrusion like an outline in 2d of a curved surface. As a reference have a look at the joint push pull tool in SU.

http://forums.sketchucation.com/viewtopic.php?t=6708

Raven

Hi Raven, for it to take on the characteristics of the surface it means that the surface has to be actually cut up - I don't expect to have that part included directly in the Extrude enhancement stuff that I've been talking about but it would be a part of the "limit depth" option in the booleans though. Well, maybe it's possible for extrude as well, I'll think about that some.

You can actually have Extrude work like that currently though if you cut the base surface up using Trim - you can also extrude individual surfaces, not just curves. See here for an example: http://moi3d.com/forum/index.php?webtag=MOI&msg=3024.4

There are 2 different ways you can thicken an individual surface like that into a solid currently - Extrude will make an object that goes out straight in one single direction, while Offset > Shell thickens an object by doing an offset operation which makes the other side follow the shape of the surface staying perpendicular to the surface at every individual piece of it (more like a "slab of even thickness everywhere" which is different than an extrusion shape).

See here for a comparison of Extrusion versus Shell and the different results that they make when thickening a surface into a solid:
http://moi3d.com/forum/index.php?webtag=MOI&msg=4791.13

- Michael

"Cut up" or better recreated based on the curves that get outlined in an n value n= extrusion height. In other words, the curves drawn on the surface get moved and scaled away from the original surface then create a new surface in the offset distance plus add 4 (or how many describe the shape in question) new resulting surfaces around this offset surface to close the mesh back up. does this make sense? I'll try and make a graphic of the above soon.

Hi Raven, yeah a sketch graphic of what you are talking about would help me understand more clearly what you are trying to describe.

There are probably some difficulties with what you are describing there... One is that on a non-planar curve it's quite difficult to create a good surface going through it just from scratch as you seem to be describing - there is not just one immediate solution to such a surface and so usually it's more practical for something like this to actually slice up an existing surface since that is better defined.

The main thing that I would be shooting for would just be something like trying to make it easier to get the same kind of result shown here just with fewer steps involved:
http://moi3d.com/forum/index.php?webtag=MOI&msg=3024.4

Is that basically the same kind of thing that you're talking about or are you thinking of something fairly different from that?

- Michael

that's exactly what I was trying to say, and like in this example it should go both ways indent and extrude.

cheers,

Raven

Here are two graphics showing what I had in mind






This shows an extrusion on a spherical surface with the resulting face not only extruded but also larger in scale then the original face.




Just a cylinder showing both the growing geometry and the consistent. The circumference grows while the height stays consistent.


Raven

Yes the function Transform / Offset / Shell makes that if you have first draw Cut - keep - a rectangle on the cylinder face :)

A speedy way to draw this rectangle is to use The New Cut "Iso curve" with keep enable ! ;)

Hi Raven, yup like Pilou writes above the Construct > Offset > Shell command will create geometry like that.

See here for a comparison of Extrusion versus Shell and the different results that they make when thickening a surface into a solid:
http://moi3d.com/forum/index.php?webtag=MOI&msg=4791.13

Maybe it could be possible for Shell to also be updated in a similar way as what I'm thinking of with Extrude to do an automatic boolean with a solid.

Currently you can get the result that you are showing there by using Edit > Trim to cut the cylinder or sphere with the curve to make a little surface fragment, then use Construct > Offset > Shell to thicken the surface into a solid slab which will produce the "uniform thickness" type result that you are showing there, then delete one face from the shelled result and it can then be joined into the main cylinder or sphere piece to get the final result.

The other surface in a case like that is generated by a "surface offset" of the original surface, and an offset of a cylinder is a larger or smaller radius cylinder, and an offset of a sphere is a larger or smaller radius sphere.

The tools for generating things that use offsets like that are located in the UI under Construct > Offset rather than in Construct > Extrude.

- Michael

hi,

one question ^^

How you active the push pull in moi ?

Call Command Extrude !
You can also make a ShortCut on it!
Or Press TAB and write Extrude

c'est quoi la différence avec une extrusion basique ?

si je fais une porte dans le bas d'un cube, je suis toujours obliger de faire opération booléenne pour enlever le morceau de la porte

oui par contre une fois que le trou est fait, là oui je peut déplacer en "push pull"

mais c'est au départ ?

Elle peut se faire aussi en suivant un chemin!
Ce que ne fera pas l'extrude "Push-Pull" automatique!

Et par rapport à SKetchup, le fait d'avoir une surface "porte" ne va pas faire une différence de volume avec extrude!

Oui mais on est bien d'accord qu'il faut encore enlever manuellement la première extrusion ? ( en mode pousser dans quelque chose )

Hi Dzeko - you can do a push/pull type operation if you have a solid and you select a face of that solid and then do an extrusion (Construct > Extrude) of the face.

When there is a face selection the generated extrusion is automatically booleaned with the base solid, either Boolean difference if you go inwards to the solid, or Boolean union if you extrude towards the outside direction.

Someday I'd like to have an option for this to also work if you are extruding curves that are positioned on the surface of a solid but currently that doesn't work, you need to select faces to do the automatic boolean mode. You can use Edit > Trim followed by Edit > Join to slice a face up into sections to prepare it for push/pulling though.

With a face selected, doing Extrude then works like this:



- Michael

A la différence de Sketchup il n'y a pas de différence automatique avec Extrude d'une face ne faisant pas partie du volume!



Par contre oui quand il y auto-intersection et suivant le sens!

A la différence de Sketchup il n'y a pas de différence automatique avec Extrude d'une face ne faisant pas partie du volume!


Merci c'est bien cela qui me turlupiner ^^

And just to clarify a bit more - for the first case like Pilou shows above, it's more normal in MoI to draw a curve object and use Boolean Difference to cut the base solid by the curve directly rather than doing an extrusion. Booleans will automatically extrude 2D curves used as cutting objects out into extrusions that go all the way through the object so you don't need to extrude them yourself in that case.

So for example if you have a solid and a curve like this:




Run Construct > Boolean > Difference to get this result, no extrude is needed for this case of cutting all the way through an object:



- Michael

i think your cube is entierly cutted

i more need this

Hi Dzeko,

> i think your cube is entierly cutted
>
> i more need this

For that type of case then yes you do need to do an extrusion.

You can do it in 2 different ways - if you want to do it like "push/pull", then you'd draw a rectangle on the front face of your box and use Edit > Trim to slice the surface of the box by that curve so that it's made of separate faces. Use Join if it split into totally separate objects. Then you can select the face and do Extrude and you'll get the auto boolean behavior as shown above.

The other way is to just extrude the curve to your desired cut size, then select the main object and run Construct > Boolean > Difference and select your just extruded piece as the cutting object.

In the future I do want to have the concept of a "depth limited" boolean so that you could control the cutting depth directly in the boolean command, but until that is ready you need to form your own cutting object by using Extrude.

- Michael

thank you M.G