* Proportional edit mode 'random' falloff

This is another proportional edit falloff that slightly randomises the
influence. It's not strictly random, it's blended with linear falloff so that
it's a bit smoother. The nice thing is that it works with all transforms, axis
locking etc, including the special ones like to sphere, shrink/fatten/etc. It
can be used for all sorts of things like roughening surfaces. I most recently
used it to add a bit of randomness to the folds of some cloth. I
made a short demo video here: http://mke3.net/blender/etc/prop_random-h264.mov

Also included nicer icons for the falloff types.

source/blender/src/transform_generics.c

@@ -88,6 +88,7 @@
 #include "BLI_arithb.h"
 #include "BLI_blenlib.h"
 #include "BLI_editVert.h"
+#include "BLI_rand.h"
 
 #include "blendef.h"
 
@@ -888,6 +889,10 @@ void calculatePropRatio(TransInfo *t)
 				case PROP_SPHERE:
 					td->factor = (float)sqrt(2*dist - dist * dist);
 					break;
+				case PROP_RANDOM:
+					BLI_srand( BLI_rand() ); /* random seed */
+					td->factor = BLI_frand()*dist;
+					break;
 				default:
 					td->factor = 1;
 				}
@@ -912,6 +917,9 @@ void calculatePropRatio(TransInfo *t)
 		case PROP_SPHERE:
 			strcpy(t->proptext, "(Sphere)");
 			break;
+		case PROP_RANDOM:
+			strcpy(t->proptext, "(Random)");
+			break;
 		default:
 			strcpy(t->proptext, "");
 		}