Hi Michael,

>>It's really easy to tell - it puts up a label on the point that actually says "On srf",

But which surface? front/back/distant. As with current snaps for "On" the side/edge of a cube in a 2d view, sometimes the snap will be on the front line/edge, sometimes on the back.

>>Basically it will only kick in when in v1 you were going to miss all snaps and your point was going down to the construction plane instead.

As with snap "on" a curve, that over-rides the grid snap, will the surface snap do the same?

>>If it does get in the way, there is an easy method to turn it off,

You have mentioned before that you dont want users to have to do that.


- manz

Is it possible then to use this 'on surface snaping' to drag and align objects over a surface nornal ?

Hi Steve,

> But which surface? front/back/distant. As with current snaps for
> "On" the side/edge of a cube in a 2d view, sometimes the snap
> will be on the front line/edge, sometimes on the back.

It will be the surface that is being displayed at that point, so the one most to the front.

Again this is very straightforward - it snaps to the object that you can see that is under your mouse, there isn't much mystery about it.

You won't really be able to grab a surface that is being displayed edge-on with this snap, surfaces like that are generally not visible (their edge curves are because edges are drawn with a thickness).


When you run into that problem with "on", the solution is generally to switch to the 3D view so you can more easily target one particular edge with your mouse. This surface snap will be similar - if the surface you want to snap on to is edge-on to your current view, you will need to switch to some other view where you can clearly see it in order to snap on to it.


> As with snap "on" a curve, that over-rides the grid snap, will the
> surface snap do the same?

For curved surfaces yes - for planar surfaces I'm going to see if I can make grid snap work with them, but I'm not quite sure how that will work yet, the grid may be relative to a base point in the object rather than the world grid...

Another thing I was thinking of was possibly only enabling the onsurface snap in the 3D view and not in the ortho views at all. Then that would not interfere with grid snap there.

Maybe I can tweak things a bit to make grid snap co-exist better with both the regular "on" snap as well as the new one though, I have an idea on that.


> You have mentioned before that you dont want users to have to do that.

Not for general simple use. But if you have some particular workflow that it ends up causing a problem for, turning it on or off will certainly be a solution for that.

- Michael

Hi PaQ,

> Is it possible then to use this 'on surface snaping' to drag
> and align objects over a surface nornal ?

Not really by itself yet - it is basically something that assists commands that pick points.

I do want to make a set of orientation commands which would be focused on doing that (moving an existing object to align with a surface normal), and certainly this snap will be a part of how some of those commands will work.

However, this new snap should allow for drawing brand new objects aligned to a surface normal right from the beginning, once I get the normal-line straight snap working.

- Michael

Hi Michael,

>>It will be the surface that is being displayed at that point, so the one most to the front.
>>Again this is very straightforward - it snaps to the object that you can see that is under your mouse, there isn't much mystery about it.

But that is how I would expect it to work now for snapping onto the edge of a cube in 2d view,.. but it does not, the snap changes from front to back (or top to bottom depending on 2d view) as you move around the edge.

>>When you run into that problem with "on", the solution is generally to switch to the 3D view so you can more easily target one particular edge with your mouse

I think it strange to have to go to 3d view to be able to correctly create a planer(2d) curve via snapping.


- manz

Hi Micheal,
Referring to your animated gif, if we were to draw a rectangle normal to a contoured surface and apply a planar surface to the rectangle, could we then use that planar surface as a sort of datum plane to draw on with this new "On Surface" command ?

~Danny~

Sounds great!

Marc

Hi Danny,

> could we then use that planar surface as a sort of datum plane to
> draw on with this new "On Surface" command ?

Yup, that will definitely work - it will be kind of a basic way to set up a drawing plane.

You actually don't have to create a rectangle first and then make a plane second, you can create the plane all in one step by using Draw solid / Plane.

- Michael

Hi Michael,
The 'What's new' in V2 sounds exciting, can't wait! and thank you Michael for being so dedicated to your software, your tech support runs rings around the big guns in the design world.

Cheers
~Danny~

Hi Steve, today I did some experimentation with making "on" snap and grid snap co-exist better.

One thing I tried was letting grid snap override on snap if your mouse was close to the grid intersection point.

That didn't really work out very well, it did let grid snap work but at a pretty normal zoom level there is always a grid point close to your mouse so it basically has the effect of disabling "on" snap entirely.

What I think I'm going to do is for "on" snap I will only let grid snap override "on" snap if the object snapped on to is a line that is actually running along a grid line.

For "on surface" snap - I will disable "on surface" snap in the ortho views if grid snap is also turned on, and maybe have an option for having it disabled in all views if grid snap is on.

I think those tune-ups will help make things work more smoothly when all kinds of snapping are simultaneously enabled.

I've also made a related tune-up to straight snap - both "on" snap and "on surface" snap will now have a lower priority than straight snap.

- Michael

Hi Michael,

Could you possibly make it so that the "on" snap is only current for selected objects?


- manz

Hi Steve,

> Could you possibly make it so that the "on" snap is only
> current for selected objects?

It should be easy for me to put in an option for that.

- Michael

Hi Steve, I think I've got the combination of on/onsrf with grid snap worked out now.

If you have grid snap enabled, doing an "on" snap on to a line that is aligned with the grid's x, y, or z axes will also get grid snap applied to it.

Similarly, if you do an "onsrf" snap on to a plane that is normal to one of those axes, grid snap will also be applied there. So for instance if you draw an axis-aligned box, you can grid snap on to points on the box's surfaces.

There are some additional settings (for now just in the moi.ini file) that will allow some control over some additional details:

[Drawing Aids]
DisableOnSrfInOrthoWhenGridSnap=y
DisableOnSrfWhenGridSnap=n
OnSnapOnlyToSelected=n


The first setting (turned on by default), disables onsrf snap in ortho views when grid snap is enabled, except still allowing it on axis-aligned planes which snap to the same grid at that plane's elevation. This should generally allow regular grid snapping kind of behavior in ortho views, but still allow you to place an "onsrf" point on to a surface in the 3D view.

The second setting (off by default) will cause onsrf to be disabled entirely when grid snap is active.


Also the last setting doesn't have to do with grid snap, but instead only enables "on" or "onsrf" snaps on to selected objects only (and construction lines) instead of all objects. That may help you gain some additional control over that snap.


Also "on" and "onsrf" will not kick in if a straight-snap line is active, which is different than v1 for "on".


There are a still a couple of snapping areas that I am going to look in to like avoiding hidden-point snaps if hidden lines are turned off, but I think that the combination of grid snap + on snaps is worked out now.

- Michael

All right, some more progress for on-surface drawing.

Now if you draw a planar object (like rectangle, circle, polygon) in the 3D view and you snap 2 points on to a common plane, it will draw the object on that plane.

So this allows for stuff like this for example:


That's just moving the mouse over different faces to draw on different planes.

There are quite a few changes to help enable this kind of direct surface drawing, still working on a few more related things though.

- Michael

I suppose that the snapping is also valuable if there is another object on the surface?

This will can be also exist when drawing on a sphere or any volume? (hoops it's on first post)

Neeeeeeeeed !!! :)

-Cool

Looking good Michael,

During a building the other day, I was thinking about an option for "project to cplane" or a possible restriction for construction, such as omit x/y/z, it could certainly help, what do you think?


- manz

Hi Steve,

> During a building the other day, I was thinking about an option for
> "project to cplane" or a possible restriction for construction, such
> as omit x/y/z, it could certainly help, what do you think?

That does happen automatically if you're picking in an ortho view, and you have Options / Snaps / Object snap options / Project to plane in ortho views enabled (on by default). It actually projects to a plane parallel to the cplane but going through the first point that you picked.

So the idea for that was to use those ortho views if you wanted to ensure planarity in the thing that you were drawing, but allow more free placement in 3D if you're picking in the 3D view.

But yeah with some new features for drawing on planes in the 3D view it could be nice to have planarity optionally more ensured in there too - while drawing a curve on a face it is pretty easy right now to snap one point of a curve for example to a point on the other side of the box and make a zig-zaggy curve instead of a planar one on a face.

But if I can make object snaps ignore hidden snap points better, that may solve that problem pretty well, so I'm going to take a look at doing that first.

re:
> such as omit x/y/z,

I'm not sure if I follow you on this one - could you describe this part a bit more?

- Michael

The next part is surface normal snap - this is a straight snap similar to tangent/perpendicular snap:



Still a little bit of work to finish this one up, I think for spots where multiple surfaces are involved, like a corner where several faces meet, I will only take the surface normal if only one of those faces is selected. Otherwise I think there will be too many tracking lines to deal with.

- Michael