[Bf-committers] editmesh.c: New User Iterative Smoothing, New Mesh Wrinkle Specials Function

Robert Tiess bf-committers@blender.org
Thu, 19 Feb 2004 10:10:39 -0500

Robert Wenzlaff wrote

> What you propose here is probably best impalement as a "Make 
> Displacement real" function.  That way the existing displacement code 
> is re-used.  There have been several other requests for this as well. 
> When I get a break, I'll look at it.  (Also working on adaptive 
> subdivide for displace/radiosity.) 

Hi!  I did not want to confuse what my Wrinkle patch code actually does
with what I consider is the unrelated idea of displacment:  displacement
is a rendertime phenomenon and deformative in a importantly distinct
way that is based on textures.

My Wrinkle patch is meant to be a real time modeling tool in the same
mesh modifying manner that Fractal Subdiv., Smooth, and vertex Noise
are offered.  The Wrinkle patch code I posted adds a new specials menu
function allowing users to directly modify ("wrinkle") selected vertices in
a mesh, the effects of which can be seen and worked with immediately in
the 3d window, to be further edited in real time by the user.

The code I provided in my previous post relating to this is extremely
small in the scheme of things (about 30 lines) and does not rely on or
have any connection with any displacement routines.

The unique results of deformation attained in the Wrinkle function are not
attainable through displacement either, since as displacement derives its
deformations from textures while the Wrinkle function deforms vertice
coordinates independent of materials based data.

Another important distinction is that the Wrinkle function can perform
precisely on a user selected number of vertices -- perhaps a forehead
region of a character's head mesh, or clothes of a character, or
anything that could benefit from anything from slight to dramatic
irregularities introduced into a mesh without having to resort to the
addition of vertices.  Displacement currently cannot offer that kind
of vertice-precise deformation.

The two can be used together to achieve fantastically irregular and
complex objects, such as more realistic rocks, 3d clouds, asteroid,
organic elements and entities -- imagine displacement on top of an
"wrinkled" mesh (partial or complete) also affected by a third factor
-- nor -- so that the nor introduces further details onto a texture
displaced mesh deformed by the wrinkle function.  Additional depths
of  realism or other artistic effects could be attained through the
combination of all these factors.

I also think a "make displacement real" function could be very useful
too, but that would still be a materials/texture-dependent deformation
function, while Specials menu functions are distinct in my mind because
they mostly exist for actual manipulation of mesh shapes.

I hope I make sense :-)  Thanks for writing.