Merge various small changes from render branch:

* Division by zero fix for TNT SVD code.
* Sound fix, in case ffmpeg decode fails, don't use the samples.
* Fix for incorrect bounds of transformed objects in new raytracing code.
* Gave memory arena's a name used for allocations for easier memory
  usage debugging.
* Dupligroup no_draw option was using layers but not restrict view/render
  setting. (not a bugfix exactly but would do display list context switching
  while drawing for no reason).
* Fix objects instanced on hair particles not giving consistent results
  when the object is transformed.
* New math functions: madd_v4_v4fl, len_squared_v3v3, interp_v4_v4v4v4,
  mul_v4_m4v4, SH and form factor functions, box_minmax_bounds_m4.
* mul_m4_m4m4 and mul_m3_m3m3 now accept the same pointers for multiple
  arguments.
* endjob callback for WM jobs system.
* Geometry node uv/color layer now has search list/autocomplete.
* Various small buildsystem tweaks, not strictly needed yet in trunk.

1 files changed, 6 insertions, 4 deletions

diff --git a/intern/iksolver/intern/TNT/svd.h b/intern/iksolver/intern/TNT/svd.h
index 9ca51fa2650..9ae289474a9 100644
--- a/intern/iksolver/intern/TNT/svd.h
+++ b/intern/iksolver/intern/TNT/svd.h
@@ -349,8 +349,9 @@ void SVD(MaTRiX &A, MaTRiX &U, VecToR &s, MaTRiX &V, VecToR &work1, VecToR &work
 
 				for (j = k; j < p-1; j++) {
 					typename MaTRiX::value_type t = hypot(f,g);
-					typename MaTRiX::value_type cs = f/t;
-					typename MaTRiX::value_type sn = g/t;
+					/* division by zero checks added to avoid NaN (brecht) */
+					typename MaTRiX::value_type cs = (t == 0.0f)? 0.0f: f/t;
+					typename MaTRiX::value_type sn = (t == 0.0f)? 0.0f: g/t;
 					if (j != k) {
 						e[j-1] = t;
 					}
@@ -366,8 +367,9 @@ void SVD(MaTRiX &A, MaTRiX &U, VecToR &s, MaTRiX &V, VecToR &work1, VecToR &work
 					}
 
 					t = hypot(f,g);
-					cs = f/t;
-					sn = g/t;
+					/* division by zero checks added to avoid NaN (brecht) */
+					cs = (t == 0.0f)? 0.0f: f/t;
+					sn = (t == 0.0f)? 0.0f: g/t;
 					s[j] = t;
 					f = cs*e[j] + sn*s[j+1];
 					s[j+1] = -sn*e[j] + cs*s[j+1];