Sunday 7 December 2014

V-HACD 2.0 vs. HACD


Below some approximate convex decomposition results comparing V-HACD 2.0 and HACD.

Parameters:
  • testVHACD.exe %%i 8000000 20 0.003 4 4 0.05 0.05 0.0015 0 0 256 0.0 %%i.wrl log_%%i.txt
  • testHACD.exe %%i  2 50 0 0 1 30 2000
Score:
  • +1: V-HACD provides better decomposition than HACD
  • -1: HACD provides better decomposition than V-HACD
  • 0: V-HACD and HACD provide comparable results


V-HACD 2.0 HACD Score
18 convex-hulls


66 convex-hulls

1
18 convex-hulls

26 convex-hulls

1
16 convex-hulls

12 convex-hulls

-1
30 convex-hulls

28 convex-hulls

0
46 convex-hulls

54 convex-hulls

1
18 convex-hulls

26 convex-hulls

1
16 convex-hulls

19 convex-hulls

0
18 convex-hulls

22 convex-hulls

0
34 convex-hulls

17 convex-hulls


1
18 convex-hulls

13 convex-hulls


-1
25 convex-hulls

28 convex-hulls


1
20 convex-hulls

15 convex-hulls

-1
22 convex-hulls


16 convex-hulls


-1
42 convex-hulls

42 convex-hulls

0
9 convex-hulls

7 convex-hulls

-1
16 convex-hulls

15 convex-hulls

1

35 convex-hulls



37 convex-hulls

0
17 convex-hulls

17 convex-hulls

0
18 convex-hulls

18 convex-hulls

0
36 convex-hulls

34 convex-hulls

0
13 convex-hulls

10 convex-hulls

-1
11 convex-hulls

5 convex-hulls

-1
24 convex-hulls

20 convex-hulls

1
35 convex-hulls

36 convex-hulls

0
21 convex-hulls

13 convex-hulls

-1
15 convex-hulls

16 convex-hulls

0
9 convex-hulls
10 convex-hulls

0
41 convex-hulls

71 convex-hulls

0
22 convex-hulls

27 convex-hulls

0
47 convex-hulls

51 convex-hulls

0
23 convex-hulls

28 convex-hulls

0

3 comments:

  1. Very nice results!

    Have you changed the Convex hull computer function in V-HACD 2.0?
    I am using the convex hull class provided in HACD and was wondering if I need to upgrade to this library.

    ReplyDelete
  2. Hi Nilay,
    Yes I am using the comvex-hull code provided by bullet http://bulletphysics.org/Bullet/BulletFull/btConvexHullComputer_8h.html

    I think that V-HACD provides more consistent results. For some meshes, HACD may provide more accurate results for the same number of clusters (see the bunny model above).

    Please, give it a try and let me know what you think.

    ReplyDelete
  3. How does the collision detection work between the convex bodies after decomposition ? Do we need to use GJK for this purpose or some other approach

    ReplyDelete