Fix tabwin cols/rows computation

Signed-off-by: Olivier Fourdan <fourdan@xfce.org>

2 files changed, 21 insertions, 9 deletions

diff --git a/configure.ac.in b/configure.ac.in
index aaf122a29..6223afa17 100644
--- a/configure.ac.in
+++ b/configure.ac.in
@@ -67,6 +67,11 @@ AC_CHECK_HEADERS([stropts.h])
 AC_CHECK_FUNCS([daemon setsid])
 AC_CHECK_FUNCS(opendir)
 
+dnl Math lib is required (if available)
+MATH_LIBS=""
+AC_CHECK_LIB(m, ceil, MATH_LIBS="-lm")
+AC_SUBST([MATH_LIBS])
+
 dnl Check for i18n support
 XDT_I18N([@LINGUAS@])
 
@@ -184,7 +189,7 @@ dnl Xcomposite and related extensions
 dnl
 compositor="no"
 ENABLE_COMPOSITOR=""
-MATH_LIBS=""
+
 AC_ARG_ENABLE([compositor],
 AC_HELP_STRING([--enable-compositor], [enable compositor in xfwm4 (default)])
 AC_HELP_STRING([--disable-compositor], [disable compositor in xfwm4]),
@@ -198,12 +203,9 @@ if test x"$enable_compositor" = x"yes"; then
       ENABLE_COMPOSITOR="--enable-compositor"
       AC_DEFINE([HAVE_COMPOSITOR], [1], [Define to enable compositor])
       compositor="yes"
-      dnl Math lib is required for compositor internals
-      MATH_LIBS=" -lm"
     fi
   fi
 fi
-AC_SUBST([MATH_LIBS])
 AC_SUBST(ENABLE_COMPOSITOR)
 
 dnl
diff --git a/src/tabwin.c b/src/tabwin.c
index 9d9fb1d0d..d3beaca5b 100644
--- a/src/tabwin.c
+++ b/src/tabwin.c
@@ -44,6 +44,10 @@
 #define WIN_BORDER_WIDTH 1
 #endif
 
+#ifndef WIN_MAX_RATIO
+#define WIN_MAX_RATIO 0.80
+#endif
+
 #ifndef WIN_ALPHA
 #define WIN_ALPHA 0.85
 #endif
@@ -56,6 +60,7 @@
 #define WIN_BORDER_RADIUS 10
 #endif
 
+#include <math.h>
 #include <glib.h>
 #include <gdk/gdk.h>
 #include <gtk/gtk.h>
@@ -727,11 +732,14 @@ computeTabwinData (ScreenInfo *screen_info, TabwinWidget *tabwin_widget)
                                   "icon-size", &tabwin->icon_size, NULL);
         }
         size_request = tabwin->icon_size + tabwin->label_height + 2 * WIN_ICON_BORDER;
-        tabwin->grid_cols = (tabwin->monitor_width / (size_request)) * 0.75;
-        tabwin->grid_rows = tabwin->client_count / tabwin->grid_cols;
+        tabwin->grid_cols = (int) (floor ((double) tabwin->monitor_width * WIN_MAX_RATIO /
+                                          (double) size_request));
+        tabwin->grid_rows = (int) (ceil ((double) tabwin->client_count /
+                                         (double) tabwin->grid_cols));
 
         /* If we run out of space, halve the icon size to make more room. */
-        while ((size_request) * tabwin->grid_rows > tabwin->monitor_height - tabwin->label_height)
+        while ((size_request) * tabwin->grid_rows + tabwin->label_height >
+               ((double) tabwin->monitor_height) * WIN_MAX_RATIO)
         {
             /* Disable preview otherwise it'd be too slow */
             if (preview)
@@ -749,8 +757,10 @@ computeTabwinData (ScreenInfo *screen_info, TabwinWidget *tabwin_widget)
             size_request = tabwin->icon_size + tabwin->label_height + 2 * WIN_ICON_BORDER;
 
             /* Recalculate with new icon size */
-            tabwin->grid_cols = (tabwin->monitor_width / (size_request)) * 0.75;
-            tabwin->grid_rows = tabwin->client_count / tabwin->grid_cols + 1;
+            tabwin->grid_cols = (int) (floor ((double) tabwin->monitor_width * WIN_MAX_RATIO /
+                                              (double) size_request));
+            tabwin->grid_rows = (int) (ceil ((double) tabwin->client_count /
+                                             (double) tabwin->grid_cols));
 
             /* Shrinking the icon too much makes it hard to see */
             if (tabwin->icon_size < 8)