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Eclipix
04-16-2002, 05:20 PM
Just wanting to see if anyone can just give some basic ideas about how this works, and if possible does anyone know of any links where i could find some source code for an example?

Eclipix
04-16-2002, 06:28 PM
So, i understand that i should create a tree to store the information about what parts are connected to which parts, but what exactly am i storing. A link to a function that renders that part? Like using diplay lists sorta? Am I making any sense?

Jambolo
04-18-2002, 10:28 PM
Since it is a hierarchy, you should think of it as grouping instead linking. Each "group" or "node" contains objects and/or sub-nodes. When you do something to a group, you do it to everything in the group.

Here's an example of a hierarchy:





bicycle
+--wheel
+--spokes
+--rim
+--tire
+--wheel
+--spokes
+--rim
+--tire
+--frame
+--seat
+--drive
+--pedals
+--chains
+--gears
+--handlebar



In the case of modeling a person, a very simple hierarchy would look like this. Note that it does not appear to be organized into groups like the bicycle above. Nonetheless, it is still treated by the code as if it is made up of groups -- moving the torso will move the hands, too.





hips
+--upper leg
+--lower leg
+--foot
+--upper leg
+--lower leg
+--foot
+--torso
+--head
+--shoulders
+--upper arm
+--lower arm
+--hand
+--upper arm
+--lower arm
+--hand


As far as what goes in each node, it depends on what you are going to do with the hierarchy. Generally, each node contains the geometry for the node and a list of sub-nodes and their locations and orientations relative to the node.


[This message has been edited by Jambolo (edited 04-19-2002).]

Indiana
04-20-2002, 09:52 PM
My personal favourite resource: http://mitglied.lycos.de/mspoerl/m_a_charanimfaq.html