[Bf-committers] Displacement mapping and the return of Projection painting proposal

car bf-committers@blender.org
Sun, 4 Jan 2004 13:40:21 -0500

This is just quick thoughts for what 'CAN' already be done. I repeat 
As you know I have been trying to get somebody motivated to recreate 
the projection painting in blender to be faster and have a texture map 
painting feature. While I have been unsucessful at getting the goal. 
One part of hope just came alive. DectectiveT's new Displacement 
feature has surfaced and is ready to destory the 3d world if used 
correctly :D

If the displacement mapping and projection were married together it 
could make a chewy clay Blended drink. ;)

Work flow. Create base mesh model. UV unwrap. Paint on mesh in white 
and black values to form the low poly version of displacement grooves 
for the mesh. Paint in super fine details, render in Blender and the 
super fine details would be auto subdivided to show up in the render as 
a finely detailed model that looks like it took 3 million polys to 
create but in truth is only 1000.

Now what would be the fastest method to this would be a quick UV 
unwrap. My thought would be Atlas UV unwrapping, it creates a mess of 
uv cords. But for projection painting it would be the welcome 
complement to the Displacement mapping.
This is a picture of Atlas mapping

What needs to be done.
an Atlas UV unwrap algorithm. Or any quick method of getting the uv's 
to unwrap quickly.
Displacement mapping to create a rudimentary preview form in the 3d 
view to work from.
Normal mapping.
A complete redo for speed in projection painting. And plus it is broken 
in 2.3

What is done.
Rudimentary projection painting.
Part one of displacement mapping.
Normal mapping math, well sort of, I talked to one coder that said that 
it is there in one of the texture channels. No real proof to it. Just a 
change of the number in the bump map tool.

Why Normal mapping? Displacement mapping takes a lot of time to compute 
if it is solely used for the details. While normal mapping is as fast 
as bump mapping, though it creates the fake bumps in all direction of 
x,y,z while bump only uses z. So normal mapping could be used for Super 
fine details and Displacement mapping could be used for the edges 

What will this do for blender. Real Clay and clean modeling. Real super 
detailed meshes for render and game engine.

What can not be done. The amount of faces and vertices. Blender begins 
to stall after to many like around 3000 on an older computer. While it 
can now handle 20,000.

Inspiration, to make blender the best free Industry used tool. Zbrush, 
costs 400$ but if blender would have had these I would have never sold 
out ;P .

So that is my new part four proposal. I have tried to keep it clean and