[Bf-blender-cvs] [14f0561] master: Bendy Bones Instability Fix - Second Attempt
Joshua Leung
noreply at git.blender.org
Mon Jun 27 16:52:33 CEST 2016
Commit: 14f056144e3e1a94188034eae71bd56c3a1feec9
Author: Joshua Leung
Date: Tue Jun 28 02:52:20 2016 +1200
Branches: master
https://developer.blender.org/rB14f056144e3e1a94188034eae71bd56c3a1feec9
Bendy Bones Instability Fix - Second Attempt
So the error seems to be in cubic_tangent_factor_circle_v3(),
which was introduced with D2001.
I've tweaked the most obvious culprit here - the epsilon factor.
It used to be 10^-7, but I've reduced it down to 10^-5 now,
and it's looking a lot more stable now :)
---------
BTW, about the derivation of the magic 0.390464 factor I briefly subbed back
as a workaround for this bug, see:
http://www.whizkidtech.redprince.net/bezier/circle/
===================================================================
M source/blender/blenkernel/intern/armature.c
M source/blender/blenlib/intern/math_geom.c
===================================================================
diff --git a/source/blender/blenkernel/intern/armature.c b/source/blender/blenkernel/intern/armature.c
index 99c9d0a..b59618f 100644
--- a/source/blender/blenkernel/intern/armature.c
+++ b/source/blender/blenkernel/intern/armature.c
@@ -634,11 +634,7 @@ void b_bone_spline_setup(bPoseChannel *pchan, int rest, Mat4 result_array[MAX_BB
}
{
-#if 0 // <--- this is currently unstable, disabling until we find a good fix
- const float circle_factor = length * (cubic_tangent_factor_circle_v3(h1, h2) / 0.75f);
-#else // <--- temporary workaround, using the old hardcoded value
- const float circle_factor = length * 0.390464f;
-#endif
+ const float circle_factor = length * (cubic_tangent_factor_circle_v3(h1, h2) / 0.75f);
const float hlength1 = bone->ease1 * circle_factor;
const float hlength2 = bone->ease2 * circle_factor;
diff --git a/source/blender/blenlib/intern/math_geom.c b/source/blender/blenlib/intern/math_geom.c
index 124f0c7..82f5279 100644
--- a/source/blender/blenlib/intern/math_geom.c
+++ b/source/blender/blenlib/intern/math_geom.c
@@ -5002,7 +5002,9 @@ float cubic_tangent_factor_circle_v3(const float tan_l[3], const float tan_r[3])
BLI_ASSERT_UNIT_V3(tan_l);
BLI_ASSERT_UNIT_V3(tan_r);
- const float eps = 1e-7f;
+ /* -7f causes instability/glitches with Bendy Bones + Custom Refs */
+ const float eps = 1e-5f;
+
const float tan_dot = dot_v3v3(tan_l, tan_r);
if (tan_dot > 1.0f - eps) {
/* no angle difference (use fallback, length wont make any difference) */
More information about the Bf-blender-cvs
mailing list