Soft Cloth Necktie created for test purposes- Info surrounding it's creation in the text


https://forum.reallusion.com/Topic235574.aspx
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By Cricky - 9 Years Ago
The Necktie was designed and Unwrapped to allow proper weight mapping of the cloth.  

The base Tie was approx. 48 polygons, but required additional structure to make it flow properly.  The image behind the Avatar shows the UV Map, and the layout of the UV's which provides a guide for  multiple points in which to weigh the cloth;

The Knot was separated as a UV seamed region, as well as the binding around the edge.  It is actually a one piece mesh, although it may appear as multiple parts in the UV.

The use of a single cloth ensures no separation of the pieces regardless of the weight mapping applied, yet it allows multiple "color" variations to be applied to areas which may require it.

The knot as shown is black to prevent movement. The top polygon of the longer tail piece is weighted black to prevent separation during erratic motions, and the binding edge is a light grey so it will allow motion, but retain it's soft sided shape. The remainder is simple  a darker grey, to prevent it from being too soft and losing it's shape when gravity pulls down on it during movement.

The Necktie has a set of bones allowing it to be shaped to conform to the characters general anatomy, then, and only then, it is converted to a soft cloth, but not before the average shape of the Avatar is achieved by positioning of the bones.

The monocle is simple a straight cylinder with multiple sections allowing it to be weight mapped on both ends to prevent it from swinging away; Attached to the Avatar's head, and soft cloth creating it's motion as the Avatar moves around. The Monocle was demonstrated before using iClone5 Rope, which is no longer an option inside iClone6, so this is my solution.


http://youtu.be/soQud_98CzA

By Lord Ashes - 9 Years Ago
I tried this, before I even read this post, and my tie keeps losing shape.
I am guessing I need to add a bit more grey into the weight map to make the shape a little more rigid.
However, c+orrect me if I am wrong but, any amount of grey will allow some movement and thus eventually the item will lose any rigid shape, no?
It is a little hard to see in the video but I think even in your video the tie starts off wider than at the end of the video.
By Cricky - 9 Years Ago
Lord Ashes (5/16/2015)
I tried this, before I even read this post, and my tie keeps losing shape.
I am guessing I need to add a bit more grey into the weight map to make the shape a little more rigid.
However, c+orrect me if I am wrong but, any amount of grey will allow some movement and thus eventually the item will lose any rigid shape, no?
It is a little hard to see in the video but I think even in your video the tie starts off wider than at the end of the video.


So you can see it closer, this is a clip where the camera is focused to look at the tie specifically.  It doesn't lose shape, it is cloth and moves. 
Dependent on the camera angle in can look like it loses width, but it does not.  The collision of the cloth against the Rigid Body shapes can affect the appearance, but it does remain the same size it started as. 
The darker the grey, the stiffer the material; this of course depends on the cloth weight chosen after the weight map is applied.  Satin is not a good choice in this case, as it is too light to retain the shape.

By Lord Ashes - 9 Years Ago
Thanks for the updated video.
So in that case, why does it not lose it shape? I was under the understanding that a absolute black color in the weight map represented a portion of the cloth that does not move at all (with respect to its parent or the world if the item has not parent). As such if the cloth is attached to a moving object, the cloth will move but the pinned spot will not move with respect to the moving object. A absolute white color, on the other hand, means that the cloth is fully movable subject to the physics applied to it (such as gravity and other forces). Colors in between (i.e. various shades of grey) indicate a non-pinned cloth that is somewhat less subject to physics applied (i.e. like white but slower to react). As a result I would think that given enough time a cloth that is (weight map) grey and a cloth that is (weight map) white should end up in the same end state except that the (weight map) grey cloth will get there slower. However, this does not seem to be the case since your tie is holding its shape.
Does this mean that the tie weight map grey is dark enough that it does not overcome the friction of gravity (and thus not losing its shape due to gravity) but not totally black (pinned) to prevent it from moving? Or did you turn gravity off for the tie?  
By Cricky - 9 Years Ago
Lord Ashes (5/17/2015)
Thanks for the updated video.
So in that case, why does it not lose it shape? I was under the understanding that a absolute black color in the weight map represented a portion of the cloth that does not move at all (with respect to its parent or the world if the item has not parent). As such if the cloth is attached to a moving object, the cloth will move but the pinned spot will not move with respect to the moving object. A absolute white color, on the other hand, means that the cloth is fully movable subject to the physics applied to it (such as gravity and other forces). Colors in between (i.e. various shades of grey) indicate a non-pinned cloth that is somewhat less subject to physics applied (i.e. like white but slower to react). As a result I would think that given enough time a cloth that is (weight map) grey and a cloth that is (weight map) white should end up in the same end state except that the (weight map) grey cloth will get there slower. However, this does not seem to be the case since your tie is holding its shape.
Does this mean that the tie weight map grey is dark enough that it does not overcome the friction of gravity (and thus not losing its shape due to gravity) but not totally black (pinned) to prevent it from moving? Or did you turn gravity off for the tie?  


Question 1 - So in that case, why does it not lose it shape?: 
Answer:  Because the edge is a separate region and weighted just enough to hold it's shape.

Question 2 and 3 - Does this mean that the tie weight map grey is dark enough that it does not overcome the friction of gravity (and thus not losing its shape due to gravity) but not totally black (pinned) to prevent it from moving? 

Answer:  The weight maps in the billboard behind the model of the 1st video are what I used.  Object Gravity was employed, because if it wasn't the tie could get stuck to a collision object and not come back down.  The initial weight maps color is just the start.  Once it stabilizes in that position, then I apply a cloth weight that makes it move the way I expect it too; sometimes light, sometimes heavy.

Shades or gradients will work, but you have to be selective as to where they are applied.  When I create something that has the intention of being a cloth item I might use in iClone6, then I set the cloth UV's up to accommodate those aspects I expect to encounter. 

Collision margins do play a significant role also.