Hi Kreten. Rhino 3 will develop the 45 degree miters by sweeping a single profile curve along these rails. In R4, a 2-rail sweep will produce the frame as a single creased surface (point editable). It's not necessary to rotate profile curves 45 degrees to make the mitered joints in Rhino. So not sure where Amapi has any advantage... Or maybe you just meant to say not necessary to align the profile curve perpendicular to the rail curve (90 degrees)?... I prefer to draw the profile curve in place on the rail curve (perpendicular to the curve). It helps me visualize exactly the proportion of the two curves. Drawing a flat profile which will be swept in a vertical position along a rail which is away from my drawing space feels very disconnected to me. So i hope to see c-plane orientation tools in Moi soon...

jonah

> In R4, a 2-rail sweep will produce the frame as a single creased surface (point editable).

Hi Jonah, I couldn't seem to replicate this - is there a special setting you used to enable a single-creased-surface result in Rhino?

Over here when I do this type of 2-rail sweep in Rhino, it generates a polysurface split along the kinks, and trying to turn on control points results in a message: Cannot turn on points for polysurfaces.

One thing you might be interested in - the result of this 2 rail sweep in MoI remains point editable despite it being a polysurface. This is because MoI supports a feature where you can edit the control points of a polysurface if the joined edges of the polysurface are natural surface edges and have the same control point structure along the joined edge. This is convenient because the output of surfacing commands with kinked input curves generate such structures. Also for example a simple box is point editable in MoI.

- Michael

Rail revolve works for this case very well. You can rail revolve, and it will miter the corners

The LWCAD system is very similair to Blender's Array tool as well. You can define the copies to be transformed and twisted relative to each other, and even 'skin' them to make spirals. It's pretty spiffy.

> Personally, if there is a confusing area in MoI, it is the Array-Grid command.
> I feel it like very non-intuitive. Now, I rather draw a lines and create array
> using Array-Curve command instead; so I would appreciate if you made
> some changes...

Hi Petr, is there anything specific that you can pinpoint that makes it feel non-intuitive to you?

There really isn't very much to it... Number of copies, and then spacing by drawing a rectangle or box as the array cell size.

Is it because you don't get the kind of dynamic preview that you typically see? I had been a little hesitant to put in that type of preview here since it can generate a pretty large number of objects...

- Michael

Well, it's hard to remember what XYZ mean, is it screen relative, or relative to global coordinates? And sometimes, when picking, it's hard to remember which direction is which. Maybe there is some way you can display 'placeholders' to show how the grid is being laid out as we pick out the unit cell size?

> is there a special setting you used to enable a single-creased-surface result in Rhino? Over here when I do this type of 2-rail >sweep in Rhino, it generates a polysurface split along the kinks, and trying to turn on control points results in a message: Cannot >turn on points for polysurfaces.

Hi Michael. Are you referring to R3 ? In R4, all surfacing commands are able to output a single creased surface (loft, sweep, extrude, etc) unless they require capping to make it a solid (like extruding a planar curve). For example, the cylinder primitive is a polysurface. But you can loft 2 circles and 2 points located at their centers to produce a single surface cylinder, whose points can be turned on. I haven't changed any of my settings in Rhino.


>One thing you might be interested in - the result of this 2 rail sweep in MoI remains point editable despite it being a polysurface. >This is because MoI supports a feature where you can edit the control points of a polysurface if the joined edges of the >polysurface are natural surface edges and have the same control point structure along the joined edge. This is convenient >because the output of surfacing commands with kinked input curves generate such structures. Also for example a simple box is >point editable in MoI.

>- Michael

That's something i remember from a thread a few months ago. It's a really great feature, especially for people who patch model with untrimmed nurbs surfaces for export to animation programs. Or for playing around with architectural ideas, it could be very easy to sketch out a block model in a Frank Gehry style ...

jonah

> Are you referring to R3 ?

No, R4...


> In R4, all surfacing commands are able to output a single creased surface
> (loft, sweep, extrude, etc) unless they require capping to make it a solid
> (like extruding a planar curve).

I'm not seeing this - over here for example lofting between 2 rectangles with style = Normal and "Do not simplify" creates a polysurface made up of 4 surfaces, not a single surface with creases. I am running a 2 month old version - maybe they changed this recently?


> But you can loft 2 circles and 2 points located at their centers to produce
> a single surface cylinder, whose points can be turned on.

Yes, but that's a special case since the circles are G1 with no creases. G1 input curves will result in single surfaces. But try it with non-G1 curves such as rectangles, do you still get a single surface?

- Michael

Hi Crusoe,

> Well, it's hard to remember what XYZ mean, is it screen relative, or relative to global coordinates?

It is relative to the grid of the view you click in. This is so that it is possible to do 2D arrays relative to different views, like do a 2D array in the front view.

For the next beta I've added a new array tool, array "Dir". This lets you create a single-column linear array, based off of 2 points that you pick. The distance between the points is the array spacing, and it goes in the direction between the 2 points.

This might be a little easier for some situations since it responds in a direction that you pick yourself.

- Michael

Hi Michael. That's strange that your output is always polysurfaces. By default, all the surfacing tools now output creased surfaces. As far as i know, there is no option to disable it. And it works for G0 polycurves also (a kink will produce a crease in the surface). Been this way for many betas, as far as i remember...

jonah

Hi Jonah,

> By default, all the surfacing tools now output creased surfaces.

This is only on your own individual Rhino copy due to a non-default registry setting:
http://news2.mcneel.com/scripts/dnewsweb.exe?cmd=article&group=rhino&item=236335&utag=

A regular default install will not behave that way.

It looks like a few others ran into it accidentally, there must have been some bug that randomized settings a bit during repeated V4 beta new version installs or something...

Historically there have been various problems with having kinked single surfaces in Rhino, for example anything involving intersections used to not work properly with them. It looks like most of that has been solved, but there still can be a couple of side-effects from using them: http://news2.mcneel.com/scripts/dnewsweb.exe?cmd=article&group=rhino&item=236264&utag= , and some other things just aren't really made with them in mind yet, for instance explode will not blow a kinked surface into separate faces which you would normally expect to be able to do...

- Michael

Well, that's what Bob Ross used to call a "happy accident"...

Funny i have the same problem on both of my computers. there is a command called "DivideAlongCreases" which creates an edges along each crease. So i mapped that to CTRL+D for quick "uncreasing" when i need to do fillets. If this is a registry mistake, i certainly don't want to fix it.... :)

jonah

Hi Michael,

>>...is there anything specific that you can pinpoint that makes it feel non-intuitive to you?

Maybe, I used an inapt word to describe it, but...
I think it is because (1) I must enter the number of copies first and (2) command doesn't allow me to rearrange the spacing and/or change a number of copies (it just terminates after entering all necessary data).
I would like to make a rectangular array using this workflow:
-Select a object to array
-Draw a rectangle or box to define a spacing
-The prompt with input field of default number of copies would appear along with points that would stand for a corner of cell (number of points would correspond to prompt's default number of copies)
-Now, I could change the number of copies either by typing value in the input fields or draging something like the corner grip (grips(?)) so rows or/and columns would (dis)appear according to previous given spacing.



Petr

Hi Petr, that's an interesting idea.

One potential problem is that I think that many people may think the grip was a way to change spacing instead of a way to change the number of items. If you grabbed the grip and moved it only a small amount (not enough to go another row), nothing visibly would change as a result of moving it... That could be a bit confusing.

How does it happen that you want to do an array but don't know the number of items that you want?

Is it because you have more of an area in mind that you want to have filled in? Sort of almost like filling in a hatch pattern or something?

- Michael

Hi Michael,


>>One potential problem is that I think that many people may think the grip was a way to
>>change spacing instead of a way to change the number of items.
>>If you grabbed the grip and moved it only a small amount (not enough to go another row),
>>nothing visibly would change as a result of moving it... That could be a bit confusing.

So "typical" grip could be for changing spacing and another type of grip (we have two kind of grips now - for scaling the image and for rotating the one) for extending the included area "discretely".


>>Is it because you have more of an area in mind that you want to have filled in?

Perhaps yes. I think it is quite useful. For example a dish drainer or a bathroom mat are this kind of stuff... You want to fill some area with objects while searching for a "form", i.e. spacing and number of copies. Anyway, the new Array-Dir command seems quite helpful from that point of view.


Petr

> So "typical" grip could be for changing spacing and another type of
> grip (we have two kind of grips now - for scaling the image and for
> rotating the one) for extending the included area "discretely".

That could work. But it is a bit difficult to think of what an "extend area" grip should look like.

Another possibility would be some mode switch drop-down in the command UI area, that would change what the grips did - either changing spacing or changing the area . I don't think that I'll be able to experiment with these right now though, this will have to wait for a future version.


> You want to fill some area with objects while searching for a "form", i.e.
> spacing and number of copies.

For this purpose I was thinking it might be better to be able to select a pre-drawn 2D curve as the area for the array to fill. This could be something that you would do instead of specifying number of copies, there could be a "select area curve" button on the same UI that asks for number of copies, and if you pushed it you would then be prompted to select a boundary curve instead (and I guess pick a base point), before going to the spacing stage. But again I don't think I'll have time to work on this for V1 though.


> Anyway, the new Array-Dir command seems quite helpful from that point of view.

Yeah, I was thinking this new one should give you more of an interactive feel like you were looking for, so for V1 that should help out for this kind of form experimenting.

- Michael

>>For this purpose I was thinking it might be better to be able to
>>select a pre-drawn 2D curve [...] But again I don't think I'll have
>>time to work on this for V1 though.

Nice... Yep, we let idea mature... -Petr

Question: I am a little confused :)

Hi Pilou, that's a bug - the "Pick base point" is supposed to be hidden there. This is fixed for the next beta now.

Thanks for reporting it and for paying such close attention to the UI!

- Michael