Retopo Basics: Add/Split Polys Won't Stay On Surface

[Jim_G]

Hello -

I am trying to retopologize a cube. I have a fair amount of experience retopologizing forms in an old version of 3DCoat, but things seem to have changed. The problem is that when I use the Add/Split tool to draw polygons on the cube, they don't conform to the cube's surface...if I draw outside the borders of the surface, the point gets drawn out in space.  Is there any way to make sure that any points I draw *stay* on the surface I'm trying to retopologize? 

Side note: it would be great if, in your response, you *don't* include links to outdated YouTube videos that don't have any relevance to my question. Thanks.

Edited May 9 by Jim_G

[Carlosan]

the hipoly is loaded first on sculpt room ?

is autosnap turned on in retopo room ?

[Jim_G]

2 hours ago, Carlosan said:

the hipoly is loaded first on sculpt room ?

is utopick turned on in retopo room ?

I'm sorry, I don't have the slightest idea what either of those phrases mean. Here is what I have done so far (and I admit this is not something that anyone would probably ever do for a real project):

1. Build a 1-meter cube in another modeling program. (I scale it up to 100 meters, because otherwise it comes in much too small to work with.  I don't know why 3DCoat does that, because I have "Measure Units" set to "Meters" in Viewport Preferences...but never mind that for now.)


2. In 3DCoat, go to the Retopo room and use File --> Import --> Reference Mesh to select the cube model from my desktop and load it into 3DCoat.

3. Very carefully, use the Add/Split, Quads, Move, and Slide Vertices tools to draw quad polys that match the edges of the cube. This is *extremely* difficult, because unless I work only in orthographic views, the vertices tend to slide off the model and out into empty space.

My goal here is to get some kind of understanding of the basic workflow for retopologizing an imported model with some degree of precision, particularly a model with sharp edges. All the videos I've watched on the topic seem to either use versions of 3DCoat that are years out of date, very loose in terms of topology, or otherwise not very helpful in communicating the basic concepts.

Any feedback you can offer will be much appreciated. I'm attaching the cube OBJ and the 3DCoat file for reference.

 

cube_retopo.3b cube_250509.obj

Edited May 10 by Jim_G

[Carlosan]

There is 2 types or "snap"

For organic and hard surface models, use Auto Snap option on middle of top panel

 

For precise snap as you mention, also activate on View Menu > Snap to Low Poly Vertices

 

To avoid any slide off

 

Hope this help