Jump to content


on model 3d painting


15 replies to this topic

#1 rouncer

    Senior Member

  • Members
  • PipPipPipPip
  • 2258 posts

Posted 05 March 2009 - 07:25 PM

Posted Image

ive nearly got on model painting working, the benefits are you can use an autowrapper and it doesnt take manual uv generation.

and I can code all my brushes just for 2d and then project them onto the model.

the only problem is its shooting through when im projecting the screen painting onto the uv map of the model, any suggestions?

(and any comments appreciated, this is a great technique!)

#2 Goz

    Senior Member

  • Members
  • PipPipPipPip
  • 574 posts

Posted 05 March 2009 - 07:40 PM

Do you mean the fact that the drawing passes through the point you want it to onto the model below?

How do you mean by projecting your brushes onto the mesh? Do you split the model up and assign each polygon its own texture (or area of a texture) and then project the 2D brush on to this texture for the current orientation? I assume if the answer to the first question is yes then you aren't using this sort of UV Atlasing.

A few more details would be handy :)

#3 rouncer

    Senior Member

  • Members
  • PipPipPipPip
  • 2258 posts

Posted 05 March 2009 - 07:48 PM

Its all using the same 1024x1024 texture.
Its a bit of a mouthful, ill do my best ->
Im taking the screen painting, which is stored in the texture the size of the screen, and then taking each triangle one at a times projected screen position, converting it to uv coordinates to take that part of the image in, then using the triangles uv render target writing it to the models texture.

im back face culling, but its when theres 2 triangles facing towards the camera in a row, they both get the image inplanted onto them.

If i draw a smiley face on the turret sponson pointing down, then it appears on the hull as well.

I think on model painting is the way to go, it comes up much neater than i expected.

#4 rouncer

    Senior Member

  • Members
  • PipPipPipPip
  • 2258 posts

Posted 05 March 2009 - 09:12 PM

i fixed the problem, no worries.

#5 rouncer

    Senior Member

  • Members
  • PipPipPipPip
  • 2258 posts

Posted 05 March 2009 - 09:56 PM

Posted Image

the problems fixed, now ive got to make a few examples! :)

what do you think?

If anyone needs a model, just ask. :)

#6 Reedbeta

    DevMaster Staff

  • Administrators
  • 4782 posts
  • LocationBellevue, WA

Posted 05 March 2009 - 09:56 PM

Hey, cool project. Model painting is one of those cool things where once it becomes widespread, everyone will wonder how they survived before it! :yes:
reedbeta.com - developer blog, OpenGL demos, and other projects

#7 rouncer

    Senior Member

  • Members
  • PipPipPipPip
  • 2258 posts

Posted 05 March 2009 - 11:59 PM

Posted Image

another test model, this model took me under an hour to put together now ive avoided manual wrapping and it just being flat textured.

#8 Goz

    Senior Member

  • Members
  • PipPipPipPip
  • 574 posts

Posted 06 March 2009 - 11:03 AM

Cool :) Any chance you could show us what the texture looks like? I'd be very interested to see it :)

#9 rouncer

    Senior Member

  • Members
  • PipPipPipPip
  • 2258 posts

Posted 06 March 2009 - 11:27 AM

Posted Image

it could do with a bit of work, its wasting lots of texels at the moment.

#10 rouncer

    Senior Member

  • Members
  • PipPipPipPip
  • 2258 posts

Posted 10 March 2009 - 11:27 AM

Posted Image
Ive now got it tesselated ready for new gen sculpting.
Its no problem, all you do is tesselate, do a few averaging passes on the model to recalc the rim normals then 2.5d pressing
boolean objects and masked brushwork can go on it. ill be projecting it onto a lowpoly displacement map next.

#11 kayanat

    New Member

  • Members
  • Pip
  • 1 posts

Posted 12 March 2009 - 05:53 AM

What painting of Picasso would be easier to make it 3D? I have an art final that is done in less than two weeks, i have to make a painting 3D in a way that would look like the painting but in a 3D format, what painting of: Diego Rivera, Picasso, Monet or Van Gogh would be easier to do??

#12 rouncer

    Senior Member

  • Members
  • PipPipPipPip
  • 2258 posts

Posted 12 March 2009 - 08:28 AM

All sounds tricky to me, depends on what software you are using, or if your doing it like me - making all the software from scratch!

#13 JarkkoL

    Senior Member

  • Members
  • PipPipPipPip
  • 458 posts

Posted 12 March 2009 - 08:36 AM

Hmh, how do you mean you get automatic uv unwrap with screen painting? I thought unwrapping was orthogonal problem to the actual painting, i.e. artist would need to first unwrap the uv's and then your paint tool would figure out which texel to write to when you draw on the model.

#14 rouncer

    Senior Member

  • Members
  • PipPipPipPip
  • 2258 posts

Posted 12 March 2009 - 11:41 AM

Yeh, you have to code both - but you dont need manual unwrap if you plan on painting on model because the uv map can be awkward to paint on because you dont have to paint onto it.
But your still not allowed to waste texels (ive fixed that problem btw.)

#15 JarkkoL

    Senior Member

  • Members
  • PipPipPipPip
  • 458 posts

Posted 15 March 2009 - 11:33 AM

How do you UV map the model then? I mean if you do say plannar mapping, you don't get unique mapping on the model thus same texel maps to multiple parts of the model. Surely manually unwrapped model would be awkward to paint to directly, but if you have unwrapped UV's, your paint app can detect which texel to update when you draw on the model. But this requires that you got uniquely mapped model.

Edit: ok, after some thought I think I understand what you are trying to say (: I.e. you use some automatic unwrapping tool which results as an unintuitive UV mapping, but because you paint directly to the model it doesn't matter. I thought that this technique somehow helped you to avoid unwrapping of the model completely (automatic or manual), which is why I was confused.

#16 tyree

    Valued Member

  • Members
  • PipPipPip
  • 240 posts

Posted 15 March 2009 - 08:33 PM

rouncer what your doing would be welcome using zbrush is great if your rendering but exporting is somewhat of a hassle





1 user(s) are reading this topic

0 members, 1 guests, 0 anonymous users