diff --git a/graphics/nxglib/Make.defs b/graphics/nxglib/Make.defs
index b2e0acd1f25..cf8226921a1 100644
--- a/graphics/nxglib/Make.defs
+++ b/graphics/nxglib/Make.defs
@@ -53,7 +53,7 @@ RCOPY2_CSRCS	= nxglib_copyrectangle_8bpp.c nxglib_copyrectangle_16bpp.c \
 		  nxglib_copyrectangle_24bpp.c nxglib_copyrectangle_32bpp.c
 RECT_CSRCS	= nxglib_rectcopy.c nxglib_rectoffset.c nxglib_vectoradd.c \
 		  nxglib_rectintersect.c nxglib_nonintersecting.c \
-		  nxglib_rectoverlap.c nxglib_nullrect.c
+		  nxglib_rectunion.c nxglib_rectoverlap.c nxglib_nullrect.c
 TRAP_CSRCS	= nxglib_runoffset.c nxglib_runcopy.c \
 		  nxglib_trapoffset.c nxglib_trapcopy.c
 COLOR_CSRCS	= nxglib_colorcopy.c
diff --git a/graphics/nxglib/nxglib_rectunion.c b/graphics/nxglib/nxglib_rectunion.c
new file mode 100644
index 00000000000..4f1c8177b89
--- /dev/null
+++ b/graphics/nxglib/nxglib_rectunion.c
@@ -0,0 +1,87 @@
+/****************************************************************************
+ * graphics/nxglib/nxsglib_rectunion.c
+ *
+ *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <nuttx/fb.h>
+#include <nuttx/nxglib.h>
+
+/****************************************************************************
+ * Pre-Processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nxgl_rectunion
+ *
+ * Description:
+ *   Given two rectanges, src1 and src2, return the larger rectangle that 
+ *   contains both, dest.
+ *
+ ****************************************************************************/
+
+void nxgl_rectunion(FAR struct nxgl_rect_s *dest,
+                    FAR const struct nxgl_rect_s *src1,
+                    FAR const struct nxgl_rect_s *src2)
+{
+  dest->pt1.x = ngl_min(src1->pt1.x, src2->pt1.x);
+  dest->pt1.y = ngl_min(src1->pt1.y, src2->pt1.y);
+  dest->pt2.x = ngl_max(src1->pt2.x, src2->pt2.x);
+  dest->pt2.y = ngl_max(src1->pt2.y, src2->pt2.y);
+}
diff --git a/include/nuttx/nxglib.h b/include/nuttx/nxglib.h
index 5edd639aaa8..b34159201bc 100644
--- a/include/nuttx/nxglib.h
+++ b/include/nuttx/nxglib.h
@@ -363,6 +363,19 @@ EXTERN void nxgl_rectintersect(FAR struct nxgl_rect_s *dest,
                                FAR const struct nxgl_rect_s *src1,
                                FAR const struct nxgl_rect_s *src2);
 
+/****************************************************************************
+ * Name: nxgl_rectunion
+ *
+ * Description:
+ *   Given two rectanges, src1 and src2, return the larger rectangle that 
+ *   contains both, dest.
+ *
+ ****************************************************************************/
+
+EXTERN void nxgl_rectunion(FAR struct nxgl_rect_s *dest,
+                           FAR const struct nxgl_rect_s *src1,
+                           FAR const struct nxgl_rect_s *src2);
+
 /****************************************************************************
  * Name: nxgl_nonintersecting
  *