Painting a straight line in ortho front/side views?

[kevjon]

I have this aircraft engine cylinder and I want to create cooling fins on the mesh using the line tool and depth channel.

 

Is there a way to draw a straight line on a curved object in a ortho view ?

 

The line tool & vertex curve tool buries itself inside the mesh and creates a dot at each end.

 

The curve stroke tool creates a weird projection as shown on my second image.

 

Any suggestions how to do straight lines ?

[PolyHertz]

"Edit Projections in Ext. Editor" will project the paint directly while ignoring the mesh curvature.

That'll work for color at least, but I have no clue if its possible with depth. :-/

Edited July 9, 2015 by PolyHertz

[Carlosan]

Hi !

Please take a look, maybe this tuto help your workflow

http://3d-coat.com/forum/index.php?showtopic=18017&hl=

 

[kevjon]

"Edit Projections in Ext. Editor" will project the paint directly while ignoring the mesh curvature.

That'll work for color at least, but I have no clue if its possible with depth. :-/

 

Hey PolyHertz thanks, that is a really cool function I did not know existed. That will come in handy for other things I want to do.

I have drawn the lines in my external editor on the correct depth layer but as you guessed it does not show in 3DC with depth. Just black lines.

[kevjon]

Hi !

Please take a look, maybe this tuto help your workflow

http://3d-coat.com/forum/index.php?showtopic=18017&hl=

 

Lines.jpg

 

Carlos, I'm very excited by what you have shown on the image of the sphere with straight lines which is exactly what I want to achieve.

 

However you link points to another thread about setting up grids?

Am I missing something ?

[Carlosan]

nope

 

i was following Taros's hints about setup 3D grids to achieve this -thats what i used-

 

Paint Room > Edit > Snap to 3D grid

Grid Placement > XYPlane

Display > front view

Any of the 4 first strokes modes -from L2R- could be useful

[kevjon]

Ahh Ok

 

I tried 2D grid and that doesn't work. Although the great thing about 2D grid it allows me to align it to my engine cylinder so I can draw my straight lines on the correct angle.

 

3D grid doesn't have an option to rotate it to match the direction of the lines on want to draw on my engine cylinder ?

 

Despite the rotation limitation it doesn't work for me anyway. I can snap to 3d grid in front ortho view (after setting it to xy) but it still creates just a point at each end of the line.

Edited July 10, 2015 by kevjon

[Carlosan]

3D grid cant be rotated

 

You could > show 2D grid > snap to 2D grid too

 

[kevjon]

2D grid is fantastic and very versatile. Thanks for making me aware of it.

 

I don't understand why you can draw on a curved surface and I can't. I just get a dot at each end of the vertex line tool and it draws through the mesh.

 

Are you using the vertex line tool or have you used a brush ? 

[Carlosan]

no line

Any of the 4 first strokes modes -from L2R- could be useful

[kevjon]

I'm not sure what it is but when using the line tool over any curved object it will not draw except for the start and end point.

 

I have tried this on 3DC default sphere object. I have also tried it on imported cylindrical meshes (obj) from my 3d application.

 

If I use the 2D or 3D grid with snapping on, it has no effect on the line tools ability to draw over curvature and I still just get a dot at each end of the line.

 

There is perhaps a checkbox somewhere in 3DC which you have checked which solves this issue, but if there is I cannot find it.

[Carlosan]

dont use line tool

[kevjon]

Its pretty hard to draw with just a brush using grid snap as the brush just wobbles off the grid as you drag it along. It is easier with a big brush but I'm trying to create fine detail and need a small brush.

 

Its pretty disappointing that 3DC doesn't have the ability to draw straight lines. except at 45° increments.

 

Having said that, thanks for all your help Carlo !

Edited July 10, 2015 by kevjon

[Carlosan]

Vox Layer Tool and Vox Extrude Tool are good for that.

Also check this video out. (He started this model in Blender but starts using 3D-Coat at 2:39 in the video.)

[kevjon]

Hi Carlo

 

I eventually found a solution to this, (although it would be a lot easier and quicker if the line tool worked on curved surfaces).

 

Setup the 2D grid and 2d snapping.

Use the Curve stroke tool and place numerous points along the length of the line, place more points on the curvier parts of the mesh which will stop the line projecting onto the surface in a distorted way (as per my first post in this thread). 

[TimmyZDesign]

Also, when you use the "draw with closed spline" option in the Stroke Mode panel ("e" key on keyboard) you can right click the points to make them sharp instead of smooth. Using this combined with snapping to the 2D or 3D grid can produce straight lines as desired.