diff --git a/src/lib/aqdiagram/placement/0BUILD b/src/lib/aqdiagram/placement/0BUILD
index 73f0952..f769747 100644
--- a/src/lib/aqdiagram/placement/0BUILD
+++ b/src/lib/aqdiagram/placement/0BUILD
@@ -61,6 +61,8 @@
 
 
     <headers dist="true" install="$(pkgincludedir)">
+      o_hlayout.h
+      o_hlayout-t.h
     </headers>
 
 
@@ -70,6 +72,9 @@
   
     <sources>
       $(local/typefiles)
+      
+      o_hlayout.c
+      o_hlayout-t.c
     </sources>
 
 
diff --git a/src/lib/aqdiagram/placement/o_hlayout-t.c b/src/lib/aqdiagram/placement/o_hlayout-t.c
new file mode 100644
index 0000000..f5f4d7c
--- /dev/null
+++ b/src/lib/aqdiagram/placement/o_hlayout-t.c
@@ -0,0 +1,201 @@
+/****************************************************************************
+ * This file is part of the project AqDiagram.
+ * AqDiagram (c) by 2023 Martin Preuss, all rights reserved.
+ *
+ * The license for this file can be found in the file COPYING which you
+ * should have received along with this file.
+ ****************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "o_hlayout-t.h"
+#include "o_hlayout.h"
+
+#include <aqdiagram/aqdg_api.h>
+
+#include <gwenhywfar/debug.h>
+
+
+
+#ifdef AQDIAGRAM_ENABLE_TESTCODE
+
+
+
+/* ------------------------------------------------------------------------------------------------
+ * forward declarations
+ * ------------------------------------------------------------------------------------------------
+ */
+
+static int GWENHYWFAR_CB test1(GWEN_TEST_MODULE *mod);
+
+static AQDG_OBJECT *_createBox10x10(uint32_t opts);
+static int _boxGetDefaultWidth10(AQDG_OBJECT *object);
+static int _boxGetDefaultHeight10(AQDG_OBJECT *object);
+
+
+
+/* ------------------------------------------------------------------------------------------------
+ * implementations
+ * ------------------------------------------------------------------------------------------------
+ */
+
+int AQDG_HLayoutObject_AddTests(GWEN_TEST_MODULE *mod)
+{
+  GWEN_TEST_MODULE *newMod;
+
+  newMod=GWEN_Test_Module_AddModule(mod, "AQDG_HLayoutObject", NULL);
+
+  GWEN_Test_Module_AddTest(newMod, "test1", test1, NULL);
+
+  return 0;
+}
+
+
+
+int test1(GWEN_UNUSED GWEN_TEST_MODULE *mod)
+{
+  AQDG_OBJECT *hlayout;
+  AQDG_OBJECT *box1;
+  AQDG_OBJECT *box2;
+  AQDG_OBJECT *box3;
+  int x;
+  int y;
+  int w;
+  int h;
+  int errors=0;
+
+  hlayout=AQDG_HLayoutObject_new(NULL, 0);
+  AQDG_Object_SetWidth(hlayout, 100);
+  AQDG_Object_SetHeight(hlayout, 50);
+  AQDG_Object_SetBorderLeft(hlayout, 2);
+  AQDG_Object_SetBorderRight(hlayout, 4);
+  AQDG_Object_SetBorderTop(hlayout, 3);
+  AQDG_Object_SetBorderBottom(hlayout, 5);
+  AQDG_Object_SetHSpacing(hlayout, 2);
+  AQDG_Object_SetVSpacing(hlayout, 3);
+
+  box1=_createBox10x10(AQDG_OBJECT_OPTIONS_STRETCHY);
+  AQDG_Object_Tree2_AddChild(hlayout, box1);
+
+  box2=_createBox10x10(AQDG_OBJECT_OPTIONS_STRETCHX | AQDG_OBJECT_OPTIONS_VALIGNCENTER);
+  AQDG_Object_Tree2_AddChild(hlayout, box2);
+
+  box3=_createBox10x10(AQDG_OBJECT_OPTIONS_VALIGNBOTTOM);
+  AQDG_Object_Tree2_AddChild(hlayout, box3);
+
+  AQDG_Object_Layout(hlayout);
+
+  x=AQDG_Object_GetRelativeX(box1);
+  y=AQDG_Object_GetRelativeY(box1);
+  w=AQDG_Object_GetWidth(box1);
+  h=AQDG_Object_GetHeight(box1);
+  DBG_INFO(AQDG_LOGDOMAIN, "x=%d, y=%d, w=%d, h=%d", x, y, w, h);
+  if (x!=2) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "X of box 1 is not 2 (%d)", x);
+    errors++;
+  }
+  if (w!=10) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "WIDTH of box 1 is not 10 (%d)", w);
+    errors++;
+  }
+  if (y!=3) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "Y of box 1 is not 3 (%d)", y);
+    errors++;
+  }
+  if (h!=42) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "HEIGHT of box 1 is not 42 (%d)", y);
+    errors++;
+  }
+
+  x=AQDG_Object_GetRelativeX(box2);
+  y=AQDG_Object_GetRelativeY(box2);
+  w=AQDG_Object_GetWidth(box2);
+  h=AQDG_Object_GetHeight(box2);
+  DBG_INFO(AQDG_LOGDOMAIN, "x=%d, y=%d, w=%d, h=%d", x, y, w, h);
+
+  if (x!=14) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "X of box 2 is not 14 (%d)", x);
+    errors++;
+  }
+  if (w!=70) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "WIDTH of box 2 is not 70 (%d)", w);
+    errors++;
+  }
+  if (y!=16) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "Y of box 2 is not 16 (%d)", y);
+    errors++;
+  }
+  if (h!=10) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "HEIGHT of box 2 is not 10 (%d)", y);
+    errors++;
+  }
+
+  x=AQDG_Object_GetRelativeX(box3);
+  y=AQDG_Object_GetRelativeY(box3);
+  w=AQDG_Object_GetWidth(box3);
+  h=AQDG_Object_GetHeight(box3);
+  DBG_INFO(AQDG_LOGDOMAIN, "x=%d, y=%d, w=%d, h=%d", x, y, w, h);
+  if (x!=86) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "X of box 3 is not 86 (%d)", x);
+    errors++;
+  }
+  if (w!=10) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "WIDTH of box 3 is not 10 (%d)", w);
+    errors++;
+  }
+  if (y!=35) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "Y of box 3 is not 35 (%d)", y);
+    errors++;
+  }
+  if (h!=10) {
+    DBG_ERROR(AQDG_LOGDOMAIN, "HEIGHT of box 3 is not 10 (%d)", y);
+    errors++;
+  }
+
+
+  return errors?GWEN_ERROR_GENERIC:0;
+}
+
+
+
+AQDG_OBJECT *_createBox10x10(uint32_t opts)
+{
+  AQDG_OBJECT *box;
+
+  box=AQDG_Object_new();
+  AQDG_Object_SetOptions(box, opts);
+  AQDG_Object_SetGetDefaultWidthFn(box, _boxGetDefaultWidth10);
+  AQDG_Object_SetGetDefaultHeightFn(box, _boxGetDefaultHeight10);
+  return box;
+}
+
+
+
+int _boxGetDefaultWidth10(AQDG_OBJECT *object)
+{
+  return 10;
+}
+
+
+
+int _boxGetDefaultHeight10(AQDG_OBJECT *object)
+{
+  return 10;
+}
+
+
+
+
+
+#else
+
+int AQDG_HLayoutObject_AddTests(GWEN_TEST_MODULE *mod)
+{
+  DBG_ERROR(GWEN_LOGDOMAIN, "AqDiagram was compiled without test code enabled.");
+  return GWEN_ERROR_GENERIC;
+}
+
+
+#endif
diff --git a/src/lib/aqdiagram/placement/o_hlayout-t.h b/src/lib/aqdiagram/placement/o_hlayout-t.h
new file mode 100644
index 0000000..a4c18e8
--- /dev/null
+++ b/src/lib/aqdiagram/placement/o_hlayout-t.h
@@ -0,0 +1,25 @@
+/****************************************************************************
+ * This file is part of the project AqDiagram.
+ * AqDiagram (c) by 2023 Martin Preuss, all rights reserved.
+ *
+ * The license for this file can be found in the file COPYING which you
+ * should have received along with this file.
+ ****************************************************************************/
+
+#ifndef AQDG_PLACEMENT_O_LAYOUT_T_H
+#define AQDG_PLACEMENT_O_LAYOUT_T_H
+
+#include <aqdiagram/aqdg_api.h>
+
+#include <gwenhywfar/gwenhywfarapi.h>
+#include <gwenhywfar/testframework.h>
+
+
+
+AQDG_API int AQDG_HLayoutObject_AddTests(GWEN_TEST_MODULE *mod);
+
+
+
+
+#endif
+
diff --git a/src/lib/aqdiagram/placement/o_hlayout.c b/src/lib/aqdiagram/placement/o_hlayout.c
new file mode 100644
index 0000000..7441b97
--- /dev/null
+++ b/src/lib/aqdiagram/placement/o_hlayout.c
@@ -0,0 +1,154 @@
+/****************************************************************************
+ * This file is part of the project AqDiagram.
+ * AqDiagram (c) by 2023 Martin Preuss, all rights reserved.
+ *
+ * The license for this file can be found in the file COPYING which you
+ * should have received along with this file.
+ ****************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "o_hlayout.h"
+
+
+/* ------------------------------------------------------------------------------------------------
+ * forward declarations
+ * ------------------------------------------------------------------------------------------------
+ */
+
+static int _layout(AQDG_OBJECT *object);
+static void _vAlignChild(AQDG_OBJECT *child, uint32_t childOpts, int parentHeight, int borderTop, int borderBottom);
+
+
+
+/* ------------------------------------------------------------------------------------------------
+ * implementations
+ * ------------------------------------------------------------------------------------------------
+ */
+
+AQDG_OBJECT *AQDG_HLayoutObject_new(AQDG_OBJECT *parent, uint32_t options)
+{
+  AQDG_OBJECT *object;
+
+  object=AQDG_Object_new();
+  AQDG_Object_SetOptions(object, options);
+
+  AQDG_Object_SetLayoutFn(object, _layout);
+
+  if (parent)
+    AQDG_Object_Tree2_AddChild(parent, object);
+  return object;
+}
+
+
+
+
+int _layout(AQDG_OBJECT *object)
+{
+  AQDG_OBJECT *child;
+  int stretchables=0;
+  int minWidth;
+  int selfWidth;
+  int selfHeight;
+  int hSpacing;
+  int borderTop;
+  int borderBottom;
+
+  selfWidth=AQDG_Object_GetWidth(object);
+  selfHeight=AQDG_Object_GetHeight(object);
+  borderTop=AQDG_Object_GetBorderTop(object);
+  borderBottom=AQDG_Object_GetBorderBottom(object);
+  hSpacing=AQDG_Object_GetHSpacing(object);
+
+  minWidth=AQDG_Object_GetBorderLeft(object);
+  child=AQDG_Object_Tree2_GetFirstChild(object);
+  while(child) {
+    int childDefWidth;
+    uint32_t childOpts;
+
+    childOpts=AQDG_Object_GetOptions(child);
+    AQDG_Object_SetRelativeX(child, minWidth);
+
+    if (childOpts & AQDG_OBJECT_OPTIONS_FIXEDWIDTH)
+      childDefWidth=AQDG_Object_GetWidth(child);
+    else {
+      childDefWidth=AQDG_Object_GetDefaultWidth(child);
+      AQDG_Object_SetWidth(child, childDefWidth);
+    }
+    minWidth+=childDefWidth;
+
+    _vAlignChild(child, childOpts, selfHeight, borderTop, borderBottom);
+
+    if (childOpts & AQDG_OBJECT_OPTIONS_STRETCHX)
+      stretchables++;
+
+    child=AQDG_Object_Tree2_GetNext(child);
+    if (child)
+      minWidth+=hSpacing;
+  }
+  minWidth+=AQDG_Object_GetBorderRight(object);
+
+  if (stretchables && (selfWidth>minWidth)) {
+    int diffWidth;
+    int toAdd;
+    int pos;
+
+    diffWidth=selfWidth-minWidth;
+    toAdd=diffWidth/stretchables;
+
+    pos=AQDG_Object_GetBorderLeft(object);
+    child=AQDG_Object_Tree2_GetFirstChild(object);
+    while(child) {
+      int w;
+
+      AQDG_Object_SetRelativeX(child, pos);
+      w=AQDG_Object_GetWidth(child);
+      if (AQDG_Object_GetOptions(child) & AQDG_OBJECT_OPTIONS_STRETCHX) {
+	w+=toAdd;
+	AQDG_Object_SetWidth(child, w);
+      }
+      pos+=w;
+      child=AQDG_Object_Tree2_GetNext(child);
+      if (child)
+	pos+=hSpacing;
+    } /* while */
+  }
+  return 0;
+}
+
+
+
+void _vAlignChild(AQDG_OBJECT *child, uint32_t childOpts, int parentHeight, int borderTop, int borderBottom)
+{
+  int childHeight;
+  int y;
+  int rawParentHeight;
+
+  rawParentHeight=parentHeight-borderTop-borderBottom;
+  if (childOpts & AQDG_OBJECT_OPTIONS_FIXEDHEIGHT)
+    childHeight=AQDG_Object_GetHeight(child);
+  else {
+    if (childOpts & AQDG_OBJECT_OPTIONS_STRETCHY)
+      childHeight=rawParentHeight;
+    else
+      childHeight=AQDG_Object_GetDefaultHeight(child);
+    AQDG_Object_SetHeight(child, childHeight);
+  }
+
+  if (childOpts & AQDG_OBJECT_OPTIONS_VALIGNBOTTOM)
+    y=parentHeight-borderBottom-childHeight;
+  else if (childOpts & AQDG_OBJECT_OPTIONS_VALIGNCENTER)
+    y=(rawParentHeight-childHeight)/2;
+  else
+    y=borderTop;
+  AQDG_Object_SetRelativeY(child, y);
+}
+
+
+
+
+
+
+
diff --git a/src/lib/aqdiagram/placement/o_hlayout.h b/src/lib/aqdiagram/placement/o_hlayout.h
new file mode 100644
index 0000000..a23ff71
--- /dev/null
+++ b/src/lib/aqdiagram/placement/o_hlayout.h
@@ -0,0 +1,24 @@
+/****************************************************************************
+ * This file is part of the project AqDiagram.
+ * AqDiagram (c) by 2023 Martin Preuss, all rights reserved.
+ *
+ * The license for this file can be found in the file COPYING which you
+ * should have received along with this file.
+ ****************************************************************************/
+
+#ifndef AQDG_PLACEMENT_O_LAYOUT_H
+#define AQDG_PLACEMENT_O_LAYOUT_H
+
+#include <aqdiagram/aqdg_api.h>
+
+#include <aqdiagram/placement/object.h>
+
+
+
+AQDG_API AQDG_OBJECT *AQDG_HLayoutObject_new(AQDG_OBJECT *parent, uint32_t options);
+
+
+
+
+#endif
+