Saturday, April 18, 2015

The ultraviolence of texture mapping

When you don't use 3d modelling software on a daily basis then it can be an astonishing time-sink when you use it.

I decided to create another ship model because the current ones are mediocre. Now every time I use Blender I try to be more efficient than the last time and to generate higher quality and more maintainable products. Also, to learn some new tricks along the way. The problem is, I am not an artist and not a modeller. I don't learn these techniques in order but I brute-force myself through whatever problem is currently at hand.

This usually works when you can think of a search phrase for googling yourself out of your misery, example:
"blender align vertices among themselves" (the solution is to scale along an axis and type 0 to force them to the same axis position).

A non-fruitful phrase for me was
"blender effective uv unwrapping".

This came out of desperation after I'd spent considerable time trying to control the unwrapping algorithms in Blender. I am today convinced that UV mapping is as much an art as modelling. A good modeller will probably think about the mapping strategy when he starts modelling.

 I am still a dabbler in all things Blender so I am pretty happy with this result. I gave up on improving the results of Blender unwrapping and tweaked a few things manually. I definately learnt a lot about planning ahead for the texture map. Topology is also key, this model uses almost no triangles, just quads.


This is after carefully aligning vertices, thereby removing jitter from the manual modelling process. I also determined which unwrapping algorithm works best for me (Smart UV project with angle ~ 85° and island margin of 0.04).
A major part of the work was also selecting edges as seams for unwrapping and retrying, tweaking etc. etc. Endless fun and desperation.

Btw this isn't even the final version, There are still some islands that can use some rotating for easier texture editing later.
Then I learnt my new favourite trick which set me at peace with Blender after all the rage.

Behold the almighty texture paint mode with face selection


In Texture Paint mode, you get to use a spray gun on your model. A spray gun is not at all precise. I am not talking about the handicap of a mouse user, drawing on a tablet will not change anything. In the best case, your drawing will smear onto other, not connected parts of the model unless you created your UV map with safety distances between the UV islands. In the worst case, you will try to zoom onto edges of border regions and try to not hit the faces beyond that edge. An impossible feat.

That is...
it is not impossible when you tap into the power of "face selection masking for painting". You can now select faces just like in edit mode. If you carelessly wipe a handful of blue ink across a few faces that does feel better than good.... it is empowering.

Of course you won't want to paint the texture in Blender, Blender itself will happily fire up your image editor for you and use the updated texture you drew there.

The texture paint mode seems best suited for marking and outlining the different parts of your model in order to flesh them out later in a real 2D image editor.

Try it!

Real artists, please comment or mail whatever comments or suggestions you have about the topic :)

No comments:

Post a Comment