Change user attribs to look for empty slot rather than using them in order.  Prevents conflict with numbered legacy slots.
diff --git a/rsProgramVertex.cpp b/rsProgramVertex.cpp
index 2be6a7d..8e59bc2 100644
--- a/rsProgramVertex.cpp
+++ b/rsProgramVertex.cpp
@@ -56,10 +56,10 @@
 static void logMatrix(const char *txt, const float *f)
 {
     LOGV("Matrix %s, %p", txt, f);
-    LOGV("%6.2f, %6.2f, %6.2f, %6.2f", f[0], f[4], f[8], f[12]);
-    LOGV("%6.2f, %6.2f, %6.2f, %6.2f", f[1], f[5], f[9], f[13]);
-    LOGV("%6.2f, %6.2f, %6.2f, %6.2f", f[2], f[6], f[10], f[14]);
-    LOGV("%6.2f, %6.2f, %6.2f, %6.2f", f[3], f[7], f[11], f[15]);
+    LOGV("%6.4f, %6.4f, %6.4f, %6.4f", f[0], f[4], f[8], f[12]);
+    LOGV("%6.4f, %6.4f, %6.4f, %6.4f", f[1], f[5], f[9], f[13]);
+    LOGV("%6.4f, %6.4f, %6.4f, %6.4f", f[2], f[6], f[10], f[14]);
+    LOGV("%6.4f, %6.4f, %6.4f, %6.4f", f[3], f[7], f[11], f[15]);
 }
 
 void ProgramVertex::setupGL(const Context *rsc, ProgramVertexState *state)