I am using the 3DS loader here:
http://www.flipcode.com/archives/Another_3DS_LoaderViewer_Class.shtml
It does a good job of loading and rendering the model, however it lacks any sense of heirarchy. As a result, all the objects in the model render at the origin.
In the code under: void Model_3DS::MainChunkProcessor(long length, long findex)
is the line:
// I left this in case anyone gets very ambitious
case KEYF3DS :
//KeyFrameChunkProcessor(h.len, ftell(bin3ds));
break;
Nobody has implemented this anywhere, and I don't see any other 3DS loaders that implement it too. People seem to only post up and until they reach this point having been sati开发者_开发百科sfied with anything rendering on to the screen at all.
What would KeyFrameChunkProcessor
look like?
Google led me here:
Keyframer chunk
---------------
id Description
---- -----------
B00A unknown
7001 See first description of this chunk
B008 Frames
B009 unknown
B002 Start object description
* B008 - Frame information
simple structure describing frame info
start end size type name
0 3 4 unsigned long start frame
4 7 4 unsigned long end frame
*B002 - Start of Object info
Subhunks
id Description
---- -----------
B010 Name & Hierarchy
B011* Name Dummy Object
B013 unknown
B014* unknown
B015 unknown
B020 Objects pivot point ?
B021 unknown
B022 unknown
B030 unknown
* B010 - Name & Hierarchy descriptor
start end size type name
0 ? ? ASCIIZ Object name
? ? ? unsigned int unknown
? ? ? unsigned int unknown
? ? ? unsigned int Hierarchy of Object
The object hierarchy is a bit complex but works like this.
Each Object in the scene is given a number to identify its
order in the tree. Also each object is orddered in the 3ds
file as it would appear in the tree.
The root object is given the number -1 ( FFFF ).
As the file is read a counter of the object number is kept.
Is the counter increments the object are children of the
previous objects.But when the pattern is broken by a number
what will be less than the current counter the hierarchy returns
to that level.
for example.
object hierarchy
name
A -1
B 0 This example is taken
C 1 from 50pman.3ds
D 2
E 1 I would really reccomend
F 4 having a look at one of the
G 5 examples with the hierarchy
H 1 numbers to help work it out.
I 7
J 8
K 0
L 10
M 11
N 0
O 13
P 14
A
+-----------------+----------------+
B K N
+----+----+ + +
C E H L O
+ + + + +
D F I M P
+ +
G J
Still not done with this chunk yet !
If the object name is $$$DUMMY then it is a dummy object
and therefore you should expect a few extra chunks.
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