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Hands
09-12-2004, 11:52 PM
Help me!!
im still learning lightwave and i face some proplems,
my first question is a bout the band-saw, what does it do exactly and will i use it much?
and my second question is about UVMaps, what is the difference between VMaps and UVmaps? and im really having a hard time understanding what they do! :( can someone explain me !?

Help plz and thanx
:)

faulknermano
09-13-2004, 01:48 AM
Help me!!
im still learning lightwave and i face some proplems,
my first question is a bout the band-saw, what does it do exactly and will i use it much?


most people do. just read the manual on what it does. after that, in the course of your modelling, you might want to add detail to your model in such a way that only bandsaw could do it. it's only that time you should use it. :)


and my second question is about UVMaps, what is the difference between VMaps and UVmaps? and im really having a hard time understanding what they do! :( can someone explain me !?


VMaps (Vertex Maps) is a whole range of maps. UV Maps or Texture VMaps are a part of the whole VMap thing.

VMaps are actually a term used to call how a point in modeler can store information. currently, native lw has these VMaps:

1.) UV Maps -> stores numeric values typically from 0.0 to 1.0. modeler uses this map to find out where that particular point in UV space is.

2.) Weight Maps -> also stores numeric values, but is usually represented as percentages: this is used by modeler, but more practically manipulated in layout for bones and for surfacing. just because it is called weight maps it doesnt mean that it is limited that use only. the point is that weight maps (like UV maps) contain values can be used in anyway you want (sort of).

3.) Morph Maps -> these maps contain _vector_ information, instead of single numeric ones. this is typically used by morph mixer in layout to move certain points into specified relative locations.

4.) Color Vertex Maps -> also contains vector info, but is used to represent color (e.g. color points).

5.) Selection Maps -> contain string info.

with lscript, you can actually embed custom VMaps to contain other data.

mattclary
09-13-2004, 05:38 AM
Why the anger icon? :confused:

Lynx3d
09-13-2004, 06:11 AM
What i found funny is that the About dialog mentions:

(...),Vmaps™ are trademarks of NewTek, Inc."
Ain't that cool? Owning a trademark on an abbreviation...



5.) Selection Maps -> contain string info.


Hm not really, actually they contain no extra data at all (0-dimensional), only a list of "mapped" points. If a point is mapped it belongs to the selection set, otherwise it doesn't, but there is no value associated with it...in case someone cares...ok, you don't :D

faulknermano
09-13-2004, 07:49 AM
Hm not really, actually they contain no extra data at all (0-dimensional), only a list of "mapped" points. If a point is mapped it belongs to the selection set, otherwise it doesn't, but there is no value associated with it...in case someone cares...ok, you don't :D

is it that the selection set is defined by a string?

Lynx3d
09-13-2004, 08:50 AM
Well at least in LWO files Vmaps are defined by type, dimension, name, an array of vertices and and a value array with <dimension> values for each vertex.
Since selection sets have dimension 0 they don't actually have a value array if i interpret the SDK correctly.
So they just associate a vertex-array with a Vmap name, i.e. store no per-vertex data.

Hm just see that metaballs (meatballs...*lol* reading the SDK is fun) store their radius in a Vmap too.

faulknermano
09-13-2004, 12:02 PM
Well at least in LWO files Vmaps are defined by type, dimension, name, an array of vertices and and a value array with <dimension> values for each vertex.
Since selection sets have dimension 0 they don't actually have a value array if i interpret the SDK correctly.
So they just associate a vertex-array with a Vmap name, i.e. store no per-vertex data.


oh ok. if i understand you correctly, there is already an implicit 'holder' for the name of the vmap, so the values you are talking about are the ones held 'dimensionally.'... ahh.. you're just being too technical. :P hehehe...

Hands
09-14-2004, 12:32 AM
:rolleyes:
First of all thank you all for replying on my basic questions.
and specially thank u faulknermano for your reply.

Im totally willing to give anything to learn LW even i face alot of proplems starting with NO ONE IN MY COUNTRY KNOWS ABOUT LIGHTWAVE! I go to training centers and ask, Center do u teach Lightwave? and the man in the front smiles and says "Ohh sure if you tell us what it is!!!!!". The only thing they teach is 3DMax and at they end of the course they expect you to model an apple and color it red!

I just like to mark out a few things. First, I AM READING THE MANUAL RIGHT NOW!. when i started learnning lightwave i bought Dan Alban's "Inside Lightwave 7" and for me it took alot of money saving. "I LIVE IN A THIRD WORLD COUNTRY BY THE WAY" so for me 50 Bugs are alot!! Anyway, i get the book, i'm very excited, i open the book and start reading the Preface, and it says, "If you haven't read the manual by now, READ IT!". I got a little bit disapointed, The Manual is Huge and the way that its wriiten doesn't give you real experience on the program. However, i started reading, and now im in Chapter 28 (Vertex Maps That Is).



After reading and re-reading Vertex Maps i have came down to a good understanding of wieght maps and how they affect bone and modelling tools influence. But i can't seem to understand WHO are 'U' and 'V'. The program talks about them as names of things i can't understand!. and to really help me understand them plz tell me what are they used for?
Like if you modeling a head why do you need U or V or V-Texture Maps? I know why you would use weight maps and color maps or Texture maps but what are UVS!

Im sorry for being so dumm but please understand that your help is mostly appreciated. thanx and reply ASAP plz!

Lynx3d
09-14-2004, 06:01 AM
I see...
i knew what "UV"s (or even "UVW"s) are before i got Lightwave...

Don't remember how exactly the Manual is structured (LW6 manuals were quite a bit different i guess) but i think it should be explained elsewhere with texturing/surfacing...
I'll give it a try to explain their use in short:
"UV"-coordinates are usually (but not necessarily) used for texture mapping. "U" and "V" therefore stand for the axis in image space, like you have X, Y and Z and 3d-space. U goes to the right and V points up.
They are used when you need more sophisticated texture mapping, i.e. when planar, cylindrical, spherical etc. mapping doesn't fit your needs. Although you often start "unwrapping" (that means projecting the 3d-model on your 2D UV-coordinates) with one of those basic mapping types. Then you can move each point in UV-space to control which part of the image gets projected on which part of a polygon.