diff --git a/panda/src/linmath/lvecBase4_src.I b/panda/src/linmath/lvecBase4_src.I
index 70a376a3bf..464cd6fa12 100644
--- a/panda/src/linmath/lvecBase4_src.I
+++ b/panda/src/linmath/lvecBase4_src.I
@@ -903,6 +903,14 @@ FLOATNAME(UnalignedLVecBase4)(const FLOATNAME(LVecBase4) &copy) {
   set(copy[0], copy[1], copy[2], copy[3]);
 }
 
+/**
+ *
+ */
+INLINE_LINMATH FLOATNAME(UnalignedLVecBase4)::
+FLOATNAME(UnalignedLVecBase4)(FLOATTYPE fill_value) {
+  fill(fill_value);
+}
+
 /**
  *
  */
@@ -912,6 +920,19 @@ FLOATNAME(UnalignedLVecBase4)(FLOATTYPE x, FLOATTYPE y, FLOATTYPE z, FLOATTYPE w
   set(x, y, z, w);
 }
 
+/**
+ * Sets each element of the vector to the indicated fill_value.  This is
+ * particularly useful for initializing to zero.
+ */
+INLINE_LINMATH void FLOATNAME(UnalignedLVecBase4)::
+fill(FLOATTYPE fill_value) {
+  TAU_PROFILE("void UnalignedLVecBase4::fill()", " ", TAU_USER);
+  _v(0) = fill_value;
+  _v(1) = fill_value;
+  _v(2) = fill_value;
+  _v(3) = fill_value;
+}
+
 /**
  *
  */
diff --git a/panda/src/linmath/lvecBase4_src.h b/panda/src/linmath/lvecBase4_src.h
index b6e1a4df35..fdd81dad4b 100644
--- a/panda/src/linmath/lvecBase4_src.h
+++ b/panda/src/linmath/lvecBase4_src.h
@@ -230,8 +230,10 @@ PUBLISHED:
 
   INLINE_LINMATH FLOATNAME(UnalignedLVecBase4)() DEFAULT_CTOR;
   INLINE_LINMATH FLOATNAME(UnalignedLVecBase4)(const FLOATNAME(LVecBase4) &copy);
+  INLINE_LINMATH FLOATNAME(UnalignedLVecBase4)(FLOATTYPE fill_value);
   INLINE_LINMATH FLOATNAME(UnalignedLVecBase4)(FLOATTYPE x, FLOATTYPE y, FLOATTYPE z, FLOATTYPE w);
 
+  INLINE_LINMATH void fill(FLOATTYPE fill_value);
   INLINE_LINMATH void set(FLOATTYPE x, FLOATTYPE y, FLOATTYPE z, FLOATTYPE w);
 
   INLINE_LINMATH FLOATTYPE operator [](int i) const;