Commit theme speed up fixes

svn path=/branches/iains-blingtastic-bucket-o-bling/; revision=3454

4 files changed, 558 insertions, 464 deletions

diff --git a/src/theme-parser.c b/src/theme-parser.c
index 1c57950e..0d9c1491 100644
--- a/src/theme-parser.c
+++ b/src/theme-parser.c
@@ -1641,8 +1641,10 @@ parse_geometry_element (GMarkupParseContext  *context,
     }
 }
 
+#if 0
 static gboolean
-check_expression (const char          *expr,
+check_expression (PosToken            *tokens,
+                  int                  n_tokens,
                   gboolean             has_object,
                   MetaTheme           *theme,
                   GMarkupParseContext *context,
@@ -1681,7 +1683,7 @@ check_expression (const char          *expr,
   env.mini_icon_height = 0;
   env.theme = theme;
   
-  if (!meta_parse_position_expression (expr,
+  if (!meta_parse_position_expression (tokens, n_tokens,
                                        &env,
                                        &x, &y,
                                        error))
@@ -1692,16 +1694,7 @@ check_expression (const char          *expr,
 
   return TRUE;
 }
-
-static char*
-optimize_expression (MetaTheme  *theme,
-                     const char *expr)
-{
-  /* We aren't expecting an error here, since we already
-   * did check_expression
-   */
-  return meta_theme_replace_constants (theme, expr, NULL);
-}
+#endif
 
 static void
 parse_draw_op_element (GMarkupParseContext  *context,
@@ -1775,6 +1768,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
           return;
         }
 
+#if 0
       if (!check_expression (x1, FALSE, info->theme, context, error))
         return;
 
@@ -1786,7 +1780,8 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (!check_expression (y2, FALSE, info->theme, context, error))
         return;
-      
+#endif
+ 
       dash_on_val = 0;
       if (dash_on_length &&
           !parse_positive_integer (dash_on_length, &dash_on_val, context, info->theme, error))
@@ -1815,10 +1810,12 @@ parse_draw_op_element (GMarkupParseContext  *context,
       op = meta_draw_op_new (META_DRAW_LINE);
 
       op->data.line.color_spec = color_spec;
-      op->data.line.x1 = optimize_expression (info->theme, x1);
-      op->data.line.y1 = optimize_expression (info->theme, y1);
-      op->data.line.x2 = optimize_expression (info->theme, x2);
-      op->data.line.y2 = optimize_expression (info->theme, y2);
+
+      op->data.line.x1 = meta_draw_spec_new (info->theme, x1, NULL);
+      op->data.line.y1 = meta_draw_spec_new (info->theme, y1, NULL);
+      op->data.line.x2 = meta_draw_spec_new (info->theme, x2, NULL);
+      op->data.line.y2 = meta_draw_spec_new (info->theme, y2, NULL);
+
       op->data.line.width = width_val;
       op->data.line.dash_on_length = dash_on_val;
       op->data.line.dash_off_length = dash_off_val;
@@ -1885,6 +1882,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
           return;
         }
 
+#if 0
       if (!check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -1896,6 +1894,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (!check_expression (height, FALSE, info->theme, context, error))
         return;
+#endif
 
       filled_val = FALSE;
       if (filled && !parse_boolean (filled, &filled_val, context, error))
@@ -1914,10 +1913,12 @@ parse_draw_op_element (GMarkupParseContext  *context,
       op = meta_draw_op_new (META_DRAW_RECTANGLE);
 
       op->data.rectangle.color_spec = color_spec;
-      op->data.rectangle.x = optimize_expression (info->theme, x);
-      op->data.rectangle.y = optimize_expression (info->theme, y);
-      op->data.rectangle.width = optimize_expression (info->theme, width);
-      op->data.rectangle.height = optimize_expression (info->theme, height);
+      op->data.rectangle.x = meta_draw_spec_new (info->theme, x, NULL);
+      op->data.rectangle.y = meta_draw_spec_new (info->theme, y, NULL);
+      op->data.rectangle.width = meta_draw_spec_new (info->theme, width, NULL);
+      op->data.rectangle.height = meta_draw_spec_new (info->theme, 
+                                                      height, NULL);
+
       op->data.rectangle.filled = filled_val;
 
       g_assert (info->op_list);
@@ -2025,7 +2026,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
             }
         }
 
-     
+#if 0     
       if (!check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -2037,6 +2038,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (!check_expression (height, FALSE, info->theme, context, error))
         return;
+#endif
 
       if (start_angle == NULL)
         {
@@ -2081,10 +2083,12 @@ parse_draw_op_element (GMarkupParseContext  *context,
       op = meta_draw_op_new (META_DRAW_ARC);
 
       op->data.arc.color_spec = color_spec;
-      op->data.arc.x = optimize_expression (info->theme, x);
-      op->data.arc.y = optimize_expression (info->theme, y);
-      op->data.arc.width = optimize_expression (info->theme, width);
-      op->data.arc.height = optimize_expression (info->theme, height);
+
+      op->data.arc.x = meta_draw_spec_new (info->theme, x, NULL);
+      op->data.arc.y = meta_draw_spec_new (info->theme, y, NULL);
+      op->data.arc.width = meta_draw_spec_new (info->theme, width, NULL);
+      op->data.arc.height = meta_draw_spec_new (info->theme, height, NULL);
+
       op->data.arc.filled = filled_val;
       op->data.arc.start_angle = start_angle_val;
       op->data.arc.extent_angle = extent_angle_val;
@@ -2138,6 +2142,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
           return;
         }
 
+#if 0
       if (!check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -2149,13 +2154,13 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (!check_expression (height, FALSE, info->theme, context, error))
         return;
-      
+#endif 
       op = meta_draw_op_new (META_DRAW_CLIP);
 
-      op->data.clip.x = optimize_expression (info->theme, x);
-      op->data.clip.y = optimize_expression (info->theme, y);
-      op->data.clip.width = optimize_expression (info->theme, width);
-      op->data.clip.height = optimize_expression (info->theme, height);
+      op->data.clip.x = meta_draw_spec_new (info->theme, x, NULL);
+      op->data.clip.y = meta_draw_spec_new (info->theme, y, NULL);
+      op->data.clip.width = meta_draw_spec_new (info->theme, width, NULL);
+      op->data.clip.height = meta_draw_spec_new (info->theme, height, NULL);
 
       g_assert (info->op_list);
       
@@ -2225,7 +2230,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
                      _("No \"alpha\" attribute on element <%s>"), element_name);
           return;
         }
-      
+#if 0
       if (!check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -2237,7 +2242,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (!check_expression (height, FALSE, info->theme, context, error))
         return;
-
+#endif
       alpha_spec = NULL;
       if (!parse_alpha (alpha, &alpha_spec, context, error))
         return;
@@ -2259,10 +2264,11 @@ parse_draw_op_element (GMarkupParseContext  *context,
 
       op->data.tint.color_spec = color_spec;
       op->data.tint.alpha_spec = alpha_spec;
-      op->data.tint.x = optimize_expression (info->theme, x);
-      op->data.tint.y = optimize_expression (info->theme, y);
-      op->data.tint.width = optimize_expression (info->theme, width);
-      op->data.tint.height = optimize_expression (info->theme, height);
+
+      op->data.tint.x = meta_draw_spec_new (info->theme, x, NULL);
+      op->data.tint.y = meta_draw_spec_new (info->theme, y, NULL);
+      op->data.tint.width = meta_draw_spec_new (info->theme, width, NULL);
+      op->data.tint.height = meta_draw_spec_new (info->theme, height, NULL);
 
       g_assert (info->op_list);
       
@@ -2325,6 +2331,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
           return;
         }
 
+#if 0
       if (!check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -2336,7 +2343,8 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (!check_expression (height, FALSE, info->theme, context, error))
         return;
-      
+#endif
+  
       type_val = meta_gradient_type_from_string (type);
       if (type_val == META_GRADIENT_LAST)
         {
@@ -2353,10 +2361,12 @@ parse_draw_op_element (GMarkupParseContext  *context,
       g_assert (info->op == NULL);
       info->op = meta_draw_op_new (META_DRAW_GRADIENT);
 
-      info->op->data.gradient.x = optimize_expression (info->theme, x);
-      info->op->data.gradient.y = optimize_expression (info->theme, y);
-      info->op->data.gradient.width = optimize_expression (info->theme, width);
-      info->op->data.gradient.height = optimize_expression (info->theme, height);
+      info->op->data.gradient.x = meta_draw_spec_new (info->theme, x, NULL);
+      info->op->data.gradient.y = meta_draw_spec_new (info->theme, y, NULL);
+      info->op->data.gradient.width = meta_draw_spec_new (info->theme, 
+                                                        width, NULL);
+      info->op->data.gradient.height = meta_draw_spec_new (info->theme,
+                                                         height, NULL);
 
       info->op->data.gradient.gradient_spec = meta_gradient_spec_new (type_val);
 
@@ -2429,7 +2439,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
                      _("No \"filename\" attribute on element <%s>"), element_name);
           return;
         }
-      
+#if 0      
       if (!check_expression (x, TRUE, info->theme, context, error))
         return;
 
@@ -2441,7 +2451,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (!check_expression (height, TRUE, info->theme, context, error))
         return;
-
+#endif
       fill_type_val = META_IMAGE_FILL_SCALE;
       if (fill_type)
         {
@@ -2493,10 +2503,12 @@ parse_draw_op_element (GMarkupParseContext  *context,
 
       op->data.image.pixbuf = pixbuf;
       op->data.image.colorize_spec = colorize_spec;
-      op->data.image.x = optimize_expression (info->theme, x);
-      op->data.image.y = optimize_expression (info->theme, y);
-      op->data.image.width = optimize_expression (info->theme, width);
-      op->data.image.height = optimize_expression (info->theme, height);
+
+      op->data.image.x = meta_draw_spec_new (info->theme, x, NULL);
+      op->data.image.y = meta_draw_spec_new (info->theme, y, NULL);
+      op->data.image.width = meta_draw_spec_new (info->theme, width, NULL);
+      op->data.image.height = meta_draw_spec_new (info->theme, height, NULL);
+
       op->data.image.alpha_spec = alpha_spec;
       op->data.image.fill_type = fill_type_val;
       
@@ -2642,7 +2654,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
                      _("No \"height\" attribute on element <%s>"), element_name);
           return;
         }
-
+#if 0
       if (!check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -2654,7 +2666,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (!check_expression (height, FALSE, info->theme, context, error))
         return;
-
+#endif
       filled_val = TRUE;
       if (filled && !parse_boolean (filled, &filled_val, context, error))
         return;
@@ -2691,10 +2703,12 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       op = meta_draw_op_new (META_DRAW_GTK_ARROW);
 
-      op->data.gtk_arrow.x = optimize_expression (info->theme, x);
-      op->data.gtk_arrow.y = optimize_expression (info->theme, y);
-      op->data.gtk_arrow.width = optimize_expression (info->theme, width);
-      op->data.gtk_arrow.height = optimize_expression (info->theme, height);
+      op->data.gtk_arrow.x = meta_draw_spec_new (info->theme, x, NULL);
+      op->data.gtk_arrow.y = meta_draw_spec_new (info->theme, y, NULL);
+      op->data.gtk_arrow.width = meta_draw_spec_new (info->theme, width, NULL);
+      op->data.gtk_arrow.height = meta_draw_spec_new (info->theme, 
+                                                      height, NULL);
+
       op->data.gtk_arrow.filled = filled_val;
       op->data.gtk_arrow.state = state_val;
       op->data.gtk_arrow.shadow = shadow_val;
@@ -2768,7 +2782,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
                      _("No \"height\" attribute on element <%s>"), element_name);
           return;
         }
-
+#if 0
       if (!check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -2780,7 +2794,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (!check_expression (height, FALSE, info->theme, context, error))
         return;
-
+#endif
       state_val = meta_gtk_state_from_string (state);
       if (((int) state_val) == -1)
         {
@@ -2803,10 +2817,11 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       op = meta_draw_op_new (META_DRAW_GTK_BOX);
 
-      op->data.gtk_box.x = optimize_expression (info->theme, x);
-      op->data.gtk_box.y = optimize_expression (info->theme, y);
-      op->data.gtk_box.width = optimize_expression (info->theme, width);
-      op->data.gtk_box.height = optimize_expression (info->theme, height);
+      op->data.gtk_box.x = meta_draw_spec_new (info->theme, x, NULL);
+      op->data.gtk_box.y = meta_draw_spec_new (info->theme, y, NULL);
+      op->data.gtk_box.width = meta_draw_spec_new (info->theme, width, NULL);
+      op->data.gtk_box.height = meta_draw_spec_new (info->theme, height, NULL);
+
       op->data.gtk_box.state = state_val;
       op->data.gtk_box.shadow = shadow_val;
       
@@ -2860,6 +2875,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
           return;
         }
       
+#if 0
       if (!check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -2868,6 +2884,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
 
       if (!check_expression (y2, FALSE, info->theme, context, error))
         return;
+#endif
 
       state_val = meta_gtk_state_from_string (state);
       if (((int) state_val) == -1)
@@ -2881,9 +2898,10 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       op = meta_draw_op_new (META_DRAW_GTK_VLINE);
 
-      op->data.gtk_vline.x = optimize_expression (info->theme, x);
-      op->data.gtk_vline.y1 = optimize_expression (info->theme, y1);
-      op->data.gtk_vline.y2 = optimize_expression (info->theme, y2);
+      op->data.gtk_vline.x = meta_draw_spec_new (info->theme, x, NULL);
+      op->data.gtk_vline.y1 = meta_draw_spec_new (info->theme, y1, NULL);
+      op->data.gtk_vline.y2 = meta_draw_spec_new (info->theme, y2, NULL);
+
       op->data.gtk_vline.state = state_val;
       
       g_assert (info->op_list);
@@ -2940,7 +2958,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
                      _("No \"height\" attribute on element <%s>"), element_name);
           return;
         }
-      
+#if 0      
       if (!check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -2952,7 +2970,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (!check_expression (height, FALSE, info->theme, context, error))
         return;
-
+#endif
       fill_type_val = META_IMAGE_FILL_SCALE;
       if (fill_type)
         {
@@ -2972,11 +2990,12 @@ parse_draw_op_element (GMarkupParseContext  *context,
         return;
       
       op = meta_draw_op_new (META_DRAW_ICON);
+      
+      op->data.icon.x = meta_draw_spec_new (info->theme, x, NULL);
+      op->data.icon.y = meta_draw_spec_new (info->theme, y, NULL);
+      op->data.icon.width = meta_draw_spec_new (info->theme, width, NULL);
+      op->data.icon.height = meta_draw_spec_new (info->theme, height, NULL);
 
-      op->data.icon.x = optimize_expression (info->theme, x);
-      op->data.icon.y = optimize_expression (info->theme, y);
-      op->data.icon.width = optimize_expression (info->theme, width);
-      op->data.icon.height = optimize_expression (info->theme, height);
       op->data.icon.alpha_spec = alpha_spec;
       op->data.icon.fill_type = fill_type_val;
       
@@ -3022,12 +3041,14 @@ parse_draw_op_element (GMarkupParseContext  *context,
           return;
         }
       
+#if 0
       if (!check_expression (x, FALSE, info->theme, context, error))
         return;
 
       if (!check_expression (y, FALSE, info->theme, context, error))
         return;
-      
+#endif
+
       /* Check last so we don't have to free it when other
        * stuff fails
        */
@@ -3041,8 +3062,9 @@ parse_draw_op_element (GMarkupParseContext  *context,
       op = meta_draw_op_new (META_DRAW_TITLE);
 
       op->data.title.color_spec = color_spec;
-      op->data.title.x = optimize_expression (info->theme, x);
-      op->data.title.y = optimize_expression (info->theme, y);
+
+      op->data.title.x = meta_draw_spec_new (info->theme, x, NULL);
+      op->data.title.y = meta_draw_spec_new (info->theme, y, NULL);
 
       g_assert (info->op_list);
       
@@ -3078,7 +3100,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
       /* x/y/width/height default to 0,0,width,height - should
        * probably do this for all the draw ops
        */
-      
+#if 0      
       if (x && !check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -3090,6 +3112,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
       
       if (height && !check_expression (height, FALSE, info->theme, context, error))
         return;
+#endif
 
       op_list = meta_theme_lookup_draw_op_list (info->theme,
                                                 name);
@@ -3118,15 +3141,16 @@ parse_draw_op_element (GMarkupParseContext  *context,
 
       meta_draw_op_list_ref (op_list);
       op->data.op_list.op_list = op_list;      
-      op->data.op_list.x = x ? optimize_expression (info->theme, x) :
-        g_strdup ("0");
-      op->data.op_list.y = y ? optimize_expression (info->theme, y) :
-        g_strdup ("0");
-      op->data.op_list.width = width ? optimize_expression (info->theme, width) :
-        g_strdup ("width");
-      op->data.op_list.height = height ?  optimize_expression (info->theme, height) :
-        g_strdup ("height");
-      
+
+      op->data.op_list.x = meta_draw_spec_new (info->theme, x ? x : "0", NULL);
+      op->data.op_list.y = meta_draw_spec_new (info->theme, y ? y : "0", NULL);
+      op->data.op_list.width = meta_draw_spec_new (info->theme, 
+                                                   width ? width : "width",
+                                                   NULL);
+      op->data.op_list.height = meta_draw_spec_new (info->theme,
+                                                    height ? height : "height",
+                                                    NULL);
+
       meta_draw_op_list_append (info->op_list, op);
 
       push_state (info, STATE_INCLUDE);
@@ -3179,6 +3203,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
         }
 
       /* These default to 0 */
+#if 0
       if (tile_xoffset && !check_expression (tile_xoffset, FALSE, info->theme, context, error))
         return;
 
@@ -3188,7 +3213,6 @@ parse_draw_op_element (GMarkupParseContext  *context,
       /* x/y/width/height default to 0,0,width,height - should
        * probably do this for all the draw ops
        */
-      
       if (x && !check_expression (x, FALSE, info->theme, context, error))
         return;
 
@@ -3206,7 +3230,7 @@ parse_draw_op_element (GMarkupParseContext  *context,
 
       if (!check_expression (tile_height, FALSE, info->theme, context, error))
         return;
-      
+#endif 
       op_list = meta_theme_lookup_draw_op_list (info->theme,
                                                 name);
       if (op_list == NULL)
@@ -3233,23 +3257,25 @@ parse_draw_op_element (GMarkupParseContext  *context,
       op = meta_draw_op_new (META_DRAW_TILE);
 
       meta_draw_op_list_ref (op_list);
+
+      op->data.tile.x = meta_draw_spec_new (info->theme, x ? x : "0", NULL);
+      op->data.tile.y = meta_draw_spec_new (info->theme, y ? y : "0", NULL);
+      op->data.tile.width = meta_draw_spec_new (info->theme,
+                                                width ? width : "width",
+                                                NULL);
+      op->data.tile.height = meta_draw_spec_new (info->theme,
+                                                 height ? height : "height",
+                                                 NULL);
+      op->data.tile.tile_xoffset = meta_draw_spec_new (info->theme,
+                                                       tile_xoffset ? tile_xoffset : "0",
+                                                       NULL);
+      op->data.tile.tile_yoffset = meta_draw_spec_new (info->theme,
+                                                       tile_yoffset ? tile_yoffset : "0",
+                                                       NULL);
+      op->data.tile.tile_width = meta_draw_spec_new (info->theme, tile_width, NULL);
+      op->data.tile.tile_height = meta_draw_spec_new (info->theme, tile_height, NULL);
+
       op->data.tile.op_list = op_list;      
-      op->data.tile.x = x ? optimize_expression (info->theme, x) :
-        g_strdup ("0");
-      op->data.tile.y = y ? optimize_expression (info->theme, y) :
-        g_strdup ("0");
-      op->data.tile.width = width ? optimize_expression (info->theme, width) :
-        g_strdup ("width");
-      op->data.tile.height = height ?  optimize_expression (info->theme, height) :
-        g_strdup ("height");
-      op->data.tile.tile_xoffset = tile_xoffset ?
-        optimize_expression (info->theme, tile_xoffset) :
-        g_strdup ("0");
-      op->data.tile.tile_yoffset = tile_yoffset ?
-        optimize_expression (info->theme, tile_yoffset) :
-        g_strdup ("0");
-      op->data.tile.tile_width = optimize_expression (info->theme, tile_width);
-      op->data.tile.tile_height = optimize_expression (info->theme, tile_height);
       
       meta_draw_op_list_append (info->op_list, op);
 
diff --git a/src/theme-viewer.c b/src/theme-viewer.c
index d4a1106b..4b97de66 100644
--- a/src/theme-viewer.c
+++ b/src/theme-viewer.c
@@ -1175,6 +1175,7 @@ static const PositionExpressionTest position_expression_tests[] = {
 static void
 run_position_expression_tests (void)
 {
+#if 0
   int i;
   MetaPositionExprEnv env;
 
@@ -1184,6 +1185,8 @@ run_position_expression_tests (void)
       GError *err;
       gboolean retval;
       const PositionExpressionTest *test;
+      PosToken *tokens;
+      int n_tokens;
       int x, y;
 
       test = &position_expression_tests[i];
@@ -1210,10 +1213,13 @@ run_position_expression_tests (void)
       env.mini_icon_height = 16;
       env.theme = NULL;
 
-      retval = meta_parse_position_expression (test->expr,
-                                               &env,
-                                               &x, &y,
-                                               &err);
+      if (err == NULL)
+        {
+          retval = meta_parse_position_expression (tokens, n_tokens,
+                                                   &env,
+                                                   &x, &y,
+                                                   &err);
+        }
 
       if (retval && err)
         g_error (_("position expression test returned TRUE but set error"));
@@ -1243,8 +1249,10 @@ run_position_expression_tests (void)
       if (err)
         g_error_free (err);
 
+      meta_pos_tokens_free (tokens, n_tokens);
       ++i;
     }
+#endif
 }
 
 #if 0
diff --git a/src/theme.c b/src/theme.c
index 92ff558f..5cd22f8a 100644
--- a/src/theme.c
+++ b/src/theme.c
@@ -60,6 +60,8 @@ static void hls_to_rgb			(gdouble	 *h,
 					 gdouble	 *l,
 					 gdouble	 *s);
 
+static MetaTheme *meta_current_theme = NULL;
+
 static GdkPixbuf *
 colorize_pixbuf (GdkPixbuf *orig,
                  GdkColor  *new_color)
@@ -1167,6 +1169,7 @@ meta_color_spec_new_from_string (const char *str,
       spec->data.blend.alpha = alpha;
       spec->data.blend.background = bg;
       spec->data.blend.foreground = fg;
+      spec->data.blend.color_set = FALSE;
     }
   else if (str[0] == 's' && str[1] == 'h' && str[2] == 'a' && str[3] == 'd' &&
            str[4] == 'e' && str[5] == '/')
@@ -1225,6 +1228,7 @@ meta_color_spec_new_from_string (const char *str,
       spec = meta_color_spec_new (META_COLOR_SPEC_SHADE);
       spec->data.shade.factor = factor;
       spec->data.shade.base = base;
+      spec->data.shade.color_set = FALSE;
     }
   else
     {
@@ -1312,49 +1316,38 @@ meta_color_spec_render (MetaColorSpec *spec,
       {
         GdkColor bg, fg;
 
-        meta_color_spec_render (spec->data.blend.background, widget, &bg);
-        meta_color_spec_render (spec->data.blend.foreground, widget, &fg);
+        if (spec->data.blend.color_set == FALSE)
+          {
+            meta_color_spec_render (spec->data.blend.background, widget, &bg);
+            meta_color_spec_render (spec->data.blend.foreground, widget, &fg);
 
-        color_composite (&bg, &fg, spec->data.blend.alpha, color);
+            color_composite (&bg, &fg, spec->data.blend.alpha, 
+                             &spec->data.blend.color);
+            spec->data.blend.color_set = TRUE;
+          }
+
+        *color = spec->data.blend.color;
       }
       break;
 
     case META_COLOR_SPEC_SHADE:
       {
-        GdkColor base;
-        
-        meta_color_spec_render (spec->data.shade.base, widget, &base);
-        
-        gtk_style_shade (&base, &base, spec->data.shade.factor);
+        if (spec->data.shade.color_set == FALSE)
+          {
+            meta_color_spec_render (spec->data.shade.base, widget, 
+                                    &spec->data.shade.color);
+            
+            gtk_style_shade (&spec->data.shade.color, 
+                             &spec->data.shade.color, spec->data.shade.factor);
+            spec->data.shade.color_set = TRUE;
+          }
 
-        *color = base;
+        *color = spec->data.shade.color;
       }
       break;
     }
 }
 
-typedef enum
-{
-  POS_TOKEN_INT,
-  POS_TOKEN_DOUBLE,
-  POS_TOKEN_OPERATOR,
-  POS_TOKEN_VARIABLE,
-  POS_TOKEN_OPEN_PAREN,
-  POS_TOKEN_CLOSE_PAREN
-} PosTokenType;
-
-typedef enum
-{
-  POS_OP_NONE,
-  POS_OP_ADD,
-  POS_OP_SUBTRACT,
-  POS_OP_MULTIPLY,
-  POS_OP_DIVIDE,
-  POS_OP_MOD,
-  POS_OP_MAX,
-  POS_OP_MIN
-} PosOperatorType;
-
 static const char*
 op_name (PosOperatorType type)
 {
@@ -1429,33 +1422,6 @@ op_from_string (const char *p,
   return POS_OP_NONE;
 }
 
-typedef struct
-{
-  PosTokenType type;
-
-  union
-  {
-    struct {
-      int val;
-    } i;
-
-    struct {
-      double val;
-    } d;
-
-    struct {
-      PosOperatorType op;
-    } o;
-
-    struct {
-      char *name;
-    } v;
-
-  } d;
-
-} PosToken;
-
-
 static void
 free_tokens (PosToken *tokens,
              int       n_tokens)
@@ -1550,6 +1516,46 @@ parse_number (const char  *p,
 
 #define IS_VARIABLE_CHAR(c) (g_ascii_isalpha ((c)) || (c) == '_')
 
+#if 0
+static void
+debug_print_tokens (PosToken *tokens,
+                    int       n_tokens)
+{
+  int i;
+  
+  for (i = 0; i < n_tokens; i++)
+    {
+      PosToken *t = &tokens[i];
+
+      g_print (" ");
+
+      switch (t->type)
+        {
+        case POS_TOKEN_INT:
+          g_print ("\"%d\"", t->d.i.val);
+          break;
+        case POS_TOKEN_DOUBLE:
+          g_print ("\"%g\"", t->d.d.val);
+          break;
+        case POS_TOKEN_OPEN_PAREN:
+          g_print ("\"(\"");
+          break;
+        case POS_TOKEN_CLOSE_PAREN:
+          g_print ("\")\"");
+          break;
+        case POS_TOKEN_VARIABLE:
+          g_print ("\"%s\"", t->d.v.name);
+          break;
+        case POS_TOKEN_OPERATOR:
+          g_print ("\"%s\"", op_name (t->d.o.op));
+          break;
+        }
+    }
+
+  g_print ("\n");
+}
+#endif
+
 static gboolean
 pos_tokenize (const char  *expr,
               PosToken   **tokens_p,
@@ -1675,46 +1681,6 @@ pos_tokenize (const char  *expr,
   return FALSE;
 }
 
-#if 0
-static void
-debug_print_tokens (PosToken *tokens,
-                    int       n_tokens)
-{
-  int i;
-  
-  for (i = 0; i < n_tokens; i++)
-    {
-      PosToken *t = &tokens[i];
-
-      g_print (" ");
-
-      switch (t->type)
-        {
-        case POS_TOKEN_INT:
-          g_print ("\"%d\"", t->d.i.val);
-          break;
-        case POS_TOKEN_DOUBLE:
-          g_print ("\"%g\"", t->d.d.val);
-          break;
-        case POS_TOKEN_OPEN_PAREN:
-          g_print ("\"(\"");
-          break;
-        case POS_TOKEN_CLOSE_PAREN:
-          g_print ("\")\"");
-          break;
-        case POS_TOKEN_VARIABLE:
-          g_print ("\"%s\"", t->d.v.name);
-          break;
-        case POS_TOKEN_OPERATOR:
-          g_print ("\"%s\"", op_name (t->d.o.op));
-          break;
-        }
-    }
-
-  g_print ("\n");
-}
-#endif
-
 typedef enum
 {
   POS_EXPR_INT,
@@ -2030,7 +1996,6 @@ pos_eval_helper (PosToken                   *tokens,
   
 #if 0
   g_print ("Pos eval helper on %d tokens:\n", n_tokens);
-  debug_print_tokens (tokens, n_tokens);
 #endif
 
   /* Our first goal is to get a list of PosExpr, essentially
@@ -2087,35 +2052,35 @@ pos_eval_helper (PosToken                   *tokens,
                * in a hash, maybe keep width/height out
                * for optimization purposes
                */
-              if (strcmp (t->d.v.name, "width") == 0)
+              if (t->d.v.name_quark == env->theme->quark_width)
                 exprs[n_exprs].d.int_val = env->rect.width;
-              else if (strcmp (t->d.v.name, "height") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_height)
                 exprs[n_exprs].d.int_val = env->rect.height;
               else if (env->object_width >= 0 &&
-                       strcmp (t->d.v.name, "object_width") == 0)
+                       t->d.v.name_quark == env->theme->quark_object_width)
                 exprs[n_exprs].d.int_val = env->object_width;
               else if (env->object_height >= 0 &&
-                       strcmp (t->d.v.name, "object_height") == 0)
+                       t->d.v.name_quark == env->theme->quark_object_height)
                 exprs[n_exprs].d.int_val = env->object_height;
-              else if (strcmp (t->d.v.name, "left_width") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_left_width)
                 exprs[n_exprs].d.int_val = env->left_width;
-              else if (strcmp (t->d.v.name, "right_width") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_right_width)
                 exprs[n_exprs].d.int_val = env->right_width;
-              else if (strcmp (t->d.v.name, "top_height") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_top_height)
                 exprs[n_exprs].d.int_val = env->top_height;
-              else if (strcmp (t->d.v.name, "bottom_height") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_bottom_height)
                 exprs[n_exprs].d.int_val = env->bottom_height;
-              else if (strcmp (t->d.v.name, "mini_icon_width") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_mini_icon_width)
                 exprs[n_exprs].d.int_val = env->mini_icon_width;
-              else if (strcmp (t->d.v.name, "mini_icon_height") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_mini_icon_height)
                 exprs[n_exprs].d.int_val = env->mini_icon_height;
-              else if (strcmp (t->d.v.name, "icon_width") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_icon_width)
                 exprs[n_exprs].d.int_val = env->icon_width;
-              else if (strcmp (t->d.v.name, "icon_height") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_icon_height)
                 exprs[n_exprs].d.int_val = env->icon_height;
-              else if (strcmp (t->d.v.name, "title_width") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_title_width)
                 exprs[n_exprs].d.int_val = env->title_width;
-              else if (strcmp (t->d.v.name, "title_height") == 0)
+              else if (t->d.v.name_quark == env->theme->quark_title_height)
                 exprs[n_exprs].d.int_val = env->title_height;
               /* In practice we only hit this code on initial theme
                * parse; after that we always optimize constants away
@@ -2232,8 +2197,7 @@ pos_eval_helper (PosToken                   *tokens,
  *   so very not worth fooling with bison, yet so very painful by hand.
  */
 static gboolean
-pos_eval (PosToken                  *tokens,
-          int                        n_tokens,
+pos_eval (MetaDrawSpec              *spec,
           const MetaPositionExprEnv *env,
           int                       *val_p,
           GError                   **err)
@@ -2242,7 +2206,7 @@ pos_eval (PosToken                  *tokens,
 
   *val_p = 0;
 
-  if (pos_eval_helper (tokens, n_tokens, env, &expr, err))
+  if (pos_eval_helper (spec->tokens, spec->n_tokens, env, &expr, err))
     {
       switch (expr.type)
         {
@@ -2269,7 +2233,7 @@ pos_eval (PosToken                  *tokens,
  */
 
 gboolean
-meta_parse_position_expression (const char                *expr,
+meta_parse_position_expression (MetaDrawSpec              *spec,
                                 const MetaPositionExprEnv *env,
                                 int                       *x_return,
                                 int                       *y_return,
@@ -2281,73 +2245,55 @@ meta_parse_position_expression (const char                *expr,
    * optionally "object_width" and object_height". Negative numbers
    * aren't allowed.
    */
-  PosToken *tokens;
-  int n_tokens;
   int val;
 
-  if (!pos_tokenize (expr, &tokens, &n_tokens, err))
+  if (spec->constant)
+    val = spec->value;
+  else
     {
-      g_assert (err == NULL || *err != NULL);
-      return FALSE;
+      if (pos_eval (spec, env, &spec->value, err) == FALSE)
+        {
+          g_assert (err == NULL || *err != NULL);
+          return FALSE;
+        }
+
+      val = spec->value;
     }
 
-#if 0
-  g_print ("Tokenized \"%s\" to --->\n", expr);
-  debug_print_tokens (tokens, n_tokens);
-#endif
+  if (x_return)
+    *x_return = env->rect.x + val;
+  if (y_return)
+    *y_return = env->rect.y + val;
 
-  if (pos_eval (tokens, n_tokens, env, &val, err))
-    {
-      if (x_return)
-        *x_return = env->rect.x + val;
-      if (y_return)
-        *y_return = env->rect.y + val;
-      free_tokens (tokens, n_tokens);
-      return TRUE;
-    }
-  else
-    {
-      g_assert (err == NULL || *err != NULL);
-      free_tokens (tokens, n_tokens);
-      return FALSE;
-    }
+  return TRUE;
 }
 
 
 gboolean
-meta_parse_size_expression (const char                *expr,
+meta_parse_size_expression (MetaDrawSpec              *spec,
                             const MetaPositionExprEnv *env,
                             int                       *val_return,
                             GError                   **err)
 {
-  PosToken *tokens;
-  int n_tokens;
   int val;
 
-  if (!pos_tokenize (expr, &tokens, &n_tokens, err))
+  if (spec->constant)
+    val = spec->value;
+  else 
     {
-      g_assert (err == NULL || *err != NULL);
-      return FALSE;
+      if (pos_eval (spec, env, &spec->value, err) == FALSE)
+        {
+          g_assert (err == NULL || *err != NULL);
+          return FALSE;
+        }
+
+      val = spec->value;
     }
 
-#if 0
-  g_print ("Tokenized \"%s\" to --->\n", expr);
-  debug_print_tokens (tokens, n_tokens);
-#endif
+  if (val_return)
+    *val_return = MAX (val, 1); /* require that sizes be at least 1x1 */
 
-  if (pos_eval (tokens, n_tokens, env, &val, err))
-    {
-      if (val_return)
-        *val_return = MAX (val, 1); /* require that sizes be at least 1x1 */
-      free_tokens (tokens, n_tokens);
-      return TRUE;
-    }
-  else
-    {
-      g_assert (err == NULL || *err != NULL);
-      free_tokens (tokens, n_tokens);
-      return FALSE;
-    }
+  return TRUE;
 }
 
 /* To do this we tokenize, replace variable tokens
@@ -2356,85 +2302,51 @@ meta_parse_size_expression (const char                *expr,
  * lookups to eval them. Obviously it's a tradeoff that
  * slows down theme load times.
  */
-char*
+gboolean
 meta_theme_replace_constants (MetaTheme   *theme,
-                              const char  *expr,
+                              PosToken    *tokens,
+                              int          n_tokens,
                               GError     **err)
 {
-  PosToken *tokens;
-  int n_tokens;
   int i;
-  GString *str;
-  char buf[G_ASCII_DTOSTR_BUF_SIZE];
   double dval;
   int ival;
+  gboolean is_constant = TRUE;
   
-  if (!pos_tokenize (expr, &tokens, &n_tokens, err))
-    {
-      g_assert (err == NULL || *err != NULL);
-      return NULL;
-    }
-
-#if 0
-  g_print ("Tokenized \"%s\" to --->\n", expr);
-  debug_print_tokens (tokens, n_tokens);
-#endif
-
-  str = g_string_new (NULL);
-
+  /* Loop through tokenized string looking for variables to replace */
   for (i = 0; i < n_tokens; i++)
     {
       PosToken *t = &tokens[i];      
 
-      /* spaces so we don't accidentally merge variables
-       * or anything like that
-       */
-      if (i > 0)
-        g_string_append_c (str, ' ');
-      
-      switch (t->type)
+      if (t->type == POS_TOKEN_VARIABLE)
         {
-        case POS_TOKEN_INT:
-          g_string_append_printf (str, "%d", t->d.i.val);
-          break;
-        case POS_TOKEN_DOUBLE:
-          g_ascii_formatd (buf, G_ASCII_DTOSTR_BUF_SIZE,
-                           "%g", t->d.d.val);
-          g_string_append (str, buf);
-          break;
-        case POS_TOKEN_OPEN_PAREN:
-          g_string_append_c (str, '(');
-          break;
-        case POS_TOKEN_CLOSE_PAREN:
-          g_string_append_c (str, ')');
-          break;
-        case POS_TOKEN_VARIABLE:
           if (meta_theme_lookup_int_constant (theme, t->d.v.name, &ival))
-            g_string_append_printf (str, "%d", ival);
+            {
+              t->type = POS_TOKEN_INT;
+              t->d.i.val = ival;
+            }
           else if (meta_theme_lookup_float_constant (theme, t->d.v.name, &dval))
             {
-              g_ascii_formatd (buf, G_ASCII_DTOSTR_BUF_SIZE,
-                               "%g", dval);
-              g_string_append (str, buf);
+              t->type = POS_TOKEN_DOUBLE;
+              t->d.d.val = dval;
             }
-          else
+          else 
             {
-              g_string_append (str, t->d.v.name);
+              /* If we've found a variable that cannot be replaced then the
+                 expression is not a constant expression and we want to 
+                 replace it with a GQuark */
+
+              t->d.v.name_quark = g_quark_from_string (t->d.v.name);
+              is_constant = FALSE;
             }
-          break;
-        case POS_TOKEN_OPERATOR:
-          g_string_append (str, op_name (t->d.o.op));
-          break;
         }
     }  
-  
-  free_tokens (tokens, n_tokens);
 
-  return g_string_free (str, FALSE);
+  return is_constant;
 }
 
 static int
-parse_x_position_unchecked (const char                *expr,
+parse_x_position_unchecked (MetaDrawSpec              *spec,
                             const MetaPositionExprEnv *env)
 {
   int retval;
@@ -2442,21 +2354,19 @@ parse_x_position_unchecked (const char                *expr,
 
   retval = 0;
   error = NULL;
-  if (!meta_parse_position_expression (expr, env,
-                                       &retval, NULL,
-                                       &error))
+  if (!meta_parse_position_expression (spec, env, &retval, NULL, &error))
     {
-      meta_warning (_("Theme contained an expression \"%s\" that resulted in an error: %s\n"),
-                    expr, error->message);
-
+      meta_warning (_("Theme contained an expression that resulted in an error: %s\n"),
+                    error->message);
+      
       g_error_free (error);
     }
-
+  
   return retval;
 }
 
 static int
-parse_y_position_unchecked (const char                *expr,
+parse_y_position_unchecked (MetaDrawSpec              *spec,
                             const MetaPositionExprEnv *env)
 {
   int retval;
@@ -2464,12 +2374,10 @@ parse_y_position_unchecked (const char                *expr,
 
   retval = 0;
   error = NULL;
-  if (!meta_parse_position_expression (expr, env,
-                                       NULL, &retval,
-                                       &error))
+  if (!meta_parse_position_expression (spec, env, NULL, &retval, &error))
     {
-      meta_warning (_("Theme contained an expression \"%s\" that resulted in an error: %s\n"),
-                    expr, error->message);
+      meta_warning (_("Theme contained an expression that resulted in an error: %s\n"),
+                    error->message);
 
       g_error_free (error);
     }
@@ -2478,7 +2386,7 @@ parse_y_position_unchecked (const char                *expr,
 }
 
 static int
-parse_size_unchecked (const char          *expr,
+parse_size_unchecked (MetaDrawSpec        *spec,
                       MetaPositionExprEnv *env)
 {
   int retval;
@@ -2486,11 +2394,10 @@ parse_size_unchecked (const char          *expr,
 
   retval = 0;
   error = NULL;
-  if (!meta_parse_size_expression (expr, env,
-                                   &retval, &error))
+  if (!meta_parse_size_expression (spec, env, &retval, &error))
     {
-      meta_warning (_("Theme contained an expression \"%s\" that resulted in an error: %s\n"),
-                    expr, error->message);
+      meta_warning (_("Theme contained an expression that resulted in an error: %s\n"),
+                    error->message);
 
       g_error_free (error);
     }
@@ -2498,6 +2405,42 @@ parse_size_unchecked (const char          *expr,
   return retval;
 }
 
+void
+meta_draw_spec_free (MetaDrawSpec *spec)
+{
+  free_tokens (spec->tokens, spec->n_tokens);
+  g_slice_free (MetaDrawSpec, spec);
+}
+
+MetaDrawSpec *
+meta_draw_spec_new (MetaTheme  *theme,
+                    const char *expr,
+                    GError    **error)
+{
+  MetaDrawSpec *spec;
+
+  spec = g_slice_new0 (MetaDrawSpec);
+
+  pos_tokenize (expr, &spec->tokens, &spec->n_tokens, NULL);
+  
+  spec->constant = meta_theme_replace_constants (theme, spec->tokens, 
+                                                 spec->n_tokens, NULL);
+  if (spec->constant) 
+    {
+      gboolean result;
+
+      g_print ("%s is constant\n", expr);
+      result = pos_eval (spec, NULL, &spec->value, error);
+      if (result == FALSE)
+        {
+          meta_draw_spec_free (spec);
+          return NULL;
+        }
+    }
+    
+  return spec;
+}
+
 MetaDrawOp*
 meta_draw_op_new (MetaDrawType type)
 {
@@ -2581,130 +2524,145 @@ meta_draw_op_free (MetaDrawOp *op)
     case META_DRAW_LINE:
       if (op->data.line.color_spec)
         meta_color_spec_free (op->data.line.color_spec);
-      g_free (op->data.line.x1);
-      g_free (op->data.line.y1);
-      g_free (op->data.line.x2);
-      g_free (op->data.line.y2);
+
+      meta_draw_spec_free (op->data.line.x1);
+      meta_draw_spec_free (op->data.line.y1);
+      meta_draw_spec_free (op->data.line.x2);
+      meta_draw_spec_free (op->data.line.y2);
       break;
 
     case META_DRAW_RECTANGLE:
       if (op->data.rectangle.color_spec)
         g_free (op->data.rectangle.color_spec);
-      g_free (op->data.rectangle.x);
-      g_free (op->data.rectangle.y);
-      g_free (op->data.rectangle.width);
-      g_free (op->data.rectangle.height);
+
+      meta_draw_spec_free (op->data.rectangle.x);
+      meta_draw_spec_free (op->data.rectangle.y);
+      meta_draw_spec_free (op->data.rectangle.width);
+      meta_draw_spec_free (op->data.rectangle.height);
       break;
 
     case META_DRAW_ARC:
       if (op->data.arc.color_spec)
         g_free (op->data.arc.color_spec);
-      g_free (op->data.arc.x);
-      g_free (op->data.arc.y);
-      g_free (op->data.arc.width);
-      g_free (op->data.arc.height);
+
+      meta_draw_spec_free (op->data.arc.x);
+      meta_draw_spec_free (op->data.arc.y);
+      meta_draw_spec_free (op->data.arc.width);
+      meta_draw_spec_free (op->data.arc.height);
       break;
 
     case META_DRAW_CLIP:
-      g_free (op->data.clip.x);
-      g_free (op->data.clip.y);
-      g_free (op->data.clip.width);
-      g_free (op->data.clip.height);
+      meta_draw_spec_free (op->data.clip.x);
+      meta_draw_spec_free (op->data.clip.y);
+      meta_draw_spec_free (op->data.clip.width);
+      meta_draw_spec_free (op->data.clip.height);
       break;
       
     case META_DRAW_TINT:
       if (op->data.tint.color_spec)
         meta_color_spec_free (op->data.tint.color_spec);
+
       if (op->data.tint.alpha_spec)
         meta_alpha_gradient_spec_free (op->data.tint.alpha_spec);
-      g_free (op->data.tint.x);
-      g_free (op->data.tint.y);
-      g_free (op->data.tint.width);
-      g_free (op->data.tint.height);
+
+      meta_draw_spec_free (op->data.tint.x);
+      meta_draw_spec_free (op->data.tint.y);
+      meta_draw_spec_free (op->data.tint.width);
+      meta_draw_spec_free (op->data.tint.height);
       break;
 
     case META_DRAW_GRADIENT:
       if (op->data.gradient.gradient_spec)
         meta_gradient_spec_free (op->data.gradient.gradient_spec);
+
       if (op->data.gradient.alpha_spec)
         meta_alpha_gradient_spec_free (op->data.gradient.alpha_spec);
-      g_free (op->data.gradient.x);
-      g_free (op->data.gradient.y);
-      g_free (op->data.gradient.width);
-      g_free (op->data.gradient.height);
+
+      meta_draw_spec_free (op->data.gradient.x);
+      meta_draw_spec_free (op->data.gradient.y);
+      meta_draw_spec_free (op->data.gradient.width);
+      meta_draw_spec_free (op->data.gradient.height);
       break;
 
     case META_DRAW_IMAGE:
       if (op->data.image.alpha_spec)
         meta_alpha_gradient_spec_free (op->data.image.alpha_spec);
+
       if (op->data.image.pixbuf)
         g_object_unref (G_OBJECT (op->data.image.pixbuf));
+
       if (op->data.image.colorize_spec)
 	meta_color_spec_free (op->data.image.colorize_spec);
+
       if (op->data.image.colorize_cache_pixbuf)
         g_object_unref (G_OBJECT (op->data.image.colorize_cache_pixbuf));
-      g_free (op->data.image.x);
-      g_free (op->data.image.y);
-      g_free (op->data.image.width);
-      g_free (op->data.image.height);
+
+      meta_draw_spec_free (op->data.image.x);
+      meta_draw_spec_free (op->data.image.y);
+      meta_draw_spec_free (op->data.image.width);
+      meta_draw_spec_free (op->data.image.height);
       break;
 
     case META_DRAW_GTK_ARROW:
-      g_free (op->data.gtk_arrow.x);
-      g_free (op->data.gtk_arrow.y);
-      g_free (op->data.gtk_arrow.width);
-      g_free (op->data.gtk_arrow.height);
+      meta_draw_spec_free (op->data.gtk_arrow.x);
+      meta_draw_spec_free (op->data.gtk_arrow.y);
+      meta_draw_spec_free (op->data.gtk_arrow.width);
+      meta_draw_spec_free (op->data.gtk_arrow.height);
       break;
 
     case META_DRAW_GTK_BOX:
-      g_free (op->data.gtk_box.x);
-      g_free (op->data.gtk_box.y);
-      g_free (op->data.gtk_box.width);
-      g_free (op->data.gtk_box.height);
+      meta_draw_spec_free (op->data.gtk_box.x);
+      meta_draw_spec_free (op->data.gtk_box.y);
+      meta_draw_spec_free (op->data.gtk_box.width);
+      meta_draw_spec_free (op->data.gtk_box.height);
       break;
 
     case META_DRAW_GTK_VLINE:
-      g_free (op->data.gtk_vline.x);
-      g_free (op->data.gtk_vline.y1);
-      g_free (op->data.gtk_vline.y2);
+      meta_draw_spec_free (op->data.gtk_vline.x);
+      meta_draw_spec_free (op->data.gtk_vline.y1);
+      meta_draw_spec_free (op->data.gtk_vline.y2);
       break;
 
     case META_DRAW_ICON:
       if (op->data.icon.alpha_spec)
         meta_alpha_gradient_spec_free (op->data.icon.alpha_spec);
-      g_free (op->data.icon.x);
-      g_free (op->data.icon.y);
-      g_free (op->data.icon.width);
-      g_free (op->data.icon.height);
+
+      meta_draw_spec_free (op->data.icon.x);
+      meta_draw_spec_free (op->data.icon.y);
+      meta_draw_spec_free (op->data.icon.width);
+      meta_draw_spec_free (op->data.icon.height);
       break;
 
     case META_DRAW_TITLE:
       if (op->data.title.color_spec)
         meta_color_spec_free (op->data.title.color_spec);
-      g_free (op->data.title.x);
-      g_free (op->data.title.y);
+
+      meta_draw_spec_free (op->data.title.x);
+      meta_draw_spec_free (op->data.title.y);
       break;
 
     case META_DRAW_OP_LIST:
       if (op->data.op_list.op_list)
         meta_draw_op_list_unref (op->data.op_list.op_list);
-      g_free (op->data.op_list.x);
-      g_free (op->data.op_list.y);
-      g_free (op->data.op_list.width);
-      g_free (op->data.op_list.height);
+
+      meta_draw_spec_free (op->data.op_list.x);
+      meta_draw_spec_free (op->data.op_list.y);
+      meta_draw_spec_free (op->data.op_list.width);
+      meta_draw_spec_free (op->data.op_list.height);
       break;
 
     case META_DRAW_TILE:
       if (op->data.tile.op_list)
         meta_draw_op_list_unref (op->data.tile.op_list);
-      g_free (op->data.tile.x);
-      g_free (op->data.tile.y);
-      g_free (op->data.tile.width);
-      g_free (op->data.tile.height);
-      g_free (op->data.tile.tile_xoffset);
-      g_free (op->data.tile.tile_yoffset);
-      g_free (op->data.tile.tile_width);
-      g_free (op->data.tile.tile_height);
+
+      meta_draw_spec_free (op->data.tile.x);
+      meta_draw_spec_free (op->data.tile.y);
+      meta_draw_spec_free (op->data.tile.width);
+      meta_draw_spec_free (op->data.tile.height);
+      meta_draw_spec_free (op->data.tile.tile_xoffset);
+      meta_draw_spec_free (op->data.tile.tile_yoffset);
+      meta_draw_spec_free (op->data.tile.tile_width);
+      meta_draw_spec_free (op->data.tile.tile_height);
       break;
     }
 
@@ -3258,7 +3216,7 @@ fill_env (MetaPositionExprEnv *env,
 
   env->title_width = info->title_layout_width;
   env->title_height = info->title_layout_height;
-  env->theme = NULL; /* not required, constants have been optimized out */
+  env->theme = meta_current_theme;
 }
 
 static void
@@ -3293,7 +3251,7 @@ meta_draw_op_draw_with_env (const MetaDrawOp    *op,
           }
 
         x1 = parse_x_position_unchecked (op->data.line.x1, env);
-        y1 = parse_y_position_unchecked (op->data.line.y1, env);
+        y1 = parse_y_position_unchecked (op->data.line.y1, env); 
         x2 = parse_x_position_unchecked (op->data.line.x2, env);
         y2 = parse_y_position_unchecked (op->data.line.y2, env);
 
@@ -4463,8 +4421,6 @@ meta_frame_style_set_validate  (MetaFrameStyleSet *style_set,
   return TRUE;
 }
 
-static MetaTheme *meta_current_theme = NULL;
-
 MetaTheme*
 meta_theme_get_current (void)
 {
@@ -4542,6 +4498,22 @@ meta_theme_new (void)
                            g_free,
                            (GDestroyNotify) meta_frame_style_set_unref);
   
+  /* Create our variable quarks so we can look up variables without
+     having to strcmp for the names */
+  theme->quark_width = g_quark_from_static_string ("width");
+  theme->quark_height = g_quark_from_static_string ("height");
+  theme->quark_object_width = g_quark_from_static_string ("object_width");
+  theme->quark_object_height = g_quark_from_static_string ("object_height");
+  theme->quark_left_width = g_quark_from_static_string ("left_width");
+  theme->quark_right_width = g_quark_from_static_string ("right_width");
+  theme->quark_top_height = g_quark_from_static_string ("top_height");
+  theme->quark_bottom_height = g_quark_from_static_string ("bottom_height");
+  theme->quark_mini_icon_width = g_quark_from_static_string ("mini_icon_width");
+  theme->quark_mini_icon_height = g_quark_from_static_string ("mini_icon_height");
+  theme->quark_icon_width = g_quark_from_static_string ("icon_width");
+  theme->quark_icon_height = g_quark_from_static_string ("icon_height");
+  theme->quark_title_width = g_quark_from_static_string ("title_width");
+  theme->quark_title_height = g_quark_from_static_string ("title_height");
   return theme;
 }
 
diff --git a/src/theme.h b/src/theme.h
index 005842ec..58a16c42 100644
--- a/src/theme.h
+++ b/src/theme.h
@@ -214,10 +214,16 @@ struct _MetaColorSpec
       MetaColorSpec *foreground;
       MetaColorSpec *background;
       double alpha;
+
+      gboolean color_set;
+      GdkColor color;
     } blend;
     struct {
       MetaColorSpec *base;
       double factor;
+
+      gboolean color_set;
+      GdkColor color;
     } shade;
   } data;
 };
@@ -275,6 +281,64 @@ typedef enum
   META_DRAW_TILE
 } MetaDrawType;
 
+typedef enum
+{
+  POS_TOKEN_INT,
+  POS_TOKEN_DOUBLE,
+  POS_TOKEN_OPERATOR,
+  POS_TOKEN_VARIABLE,
+  POS_TOKEN_OPEN_PAREN,
+  POS_TOKEN_CLOSE_PAREN
+} PosTokenType;
+
+typedef enum
+{
+  POS_OP_NONE,
+  POS_OP_ADD,
+  POS_OP_SUBTRACT,
+  POS_OP_MULTIPLY,
+  POS_OP_DIVIDE,
+  POS_OP_MOD,
+  POS_OP_MAX,
+  POS_OP_MIN
+} PosOperatorType;
+
+typedef struct
+{
+  PosTokenType type;
+
+  union
+  {
+    struct {
+      int val;
+    } i;
+
+    struct {
+      double val;
+    } d;
+
+    struct {
+      PosOperatorType op;
+    } o;
+
+    struct {
+      char *name;
+      GQuark name_quark;
+    } v;
+
+  } d;
+} PosToken;
+
+typedef struct _MetaDrawSpec
+{
+  int value;
+  
+  PosToken *tokens;
+  int n_tokens;
+
+  gboolean constant : 1; /* Does the expression contain any variables? */
+} MetaDrawSpec;
+  
 struct _MetaDrawOp
 {
   MetaDrawType type;
@@ -287,65 +351,66 @@ struct _MetaDrawOp
       int dash_on_length;
       int dash_off_length;
       int width;
-      char *x1;
-      char *y1;
-      char *x2;
-      char *y2;
+      MetaDrawSpec *x1;
+      MetaDrawSpec *y1;
+      MetaDrawSpec *x2;
+      MetaDrawSpec *y2;
     } line;
 
     struct {
       MetaColorSpec *color_spec;
       gboolean filled;
-      char *x;
-      char *y;
-      char *width;
-      char *height;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
     } rectangle;
 
     struct {
       MetaColorSpec *color_spec;
       gboolean filled;
-      char *x;
-      char *y;
-      char *width;
-      char *height;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
       double start_angle;
       double extent_angle;
     } arc;
 
     struct {
-      char *x;
-      char *y;
-      char *width;
-      char *height;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
     } clip;
     
     struct {
       MetaColorSpec *color_spec;
       MetaAlphaGradientSpec *alpha_spec;
-      char *x;
-      char *y;
-      char *width;
-      char *height;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
     } tint;
 
     struct {
       MetaGradientSpec *gradient_spec;
       MetaAlphaGradientSpec *alpha_spec;
-      char *x;
-      char *y;
-      char *width;
-      char *height;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
     } gradient;
 
     struct {
       MetaColorSpec *colorize_spec;
       MetaAlphaGradientSpec *alpha_spec;
       GdkPixbuf *pixbuf;
-      char *x;
-      char *y;
-      char *width;
-      char *height;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
+
       guint32 colorize_cache_pixel;
       GdkPixbuf *colorize_cache_pixbuf;
       MetaImageFillType fill_type;
@@ -358,61 +423,62 @@ struct _MetaDrawOp
       GtkShadowType shadow;
       GtkArrowType arrow;
       gboolean filled;
-      char *x;
-      char *y;
-      char *width;
-      char *height;
+
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
     } gtk_arrow;
 
     struct {
       GtkStateType state;
       GtkShadowType shadow;
-      char *x;
-      char *y;
-      char *width;
-      char *height;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
     } gtk_box;
 
     struct {
       GtkStateType state;
-      char *x;
-      char *y1;
-      char *y2;  
+      MetaDrawSpec *x;
+      MetaDrawSpec *y1;
+      MetaDrawSpec *y2;  
     } gtk_vline;
 
     struct {
       MetaAlphaGradientSpec *alpha_spec;
-      char *x;
-      char *y;
-      char *width;
-      char *height;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
       MetaImageFillType fill_type;
     } icon;
 
     struct {
       MetaColorSpec *color_spec;
-      char *x;
-      char *y;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
     } title;
 
     struct {
       MetaDrawOpList *op_list;
-      char *x;
-      char *y;
-      char *width;
-      char *height;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
     } op_list;
 
     struct {
       MetaDrawOpList *op_list;
-      char *x;
-      char *y;
-      char *width;
-      char *height;
-      char *tile_xoffset;
-      char *tile_yoffset;
-      char *tile_width;
-      char *tile_height;
+      MetaDrawSpec *x;
+      MetaDrawSpec *y;
+      MetaDrawSpec *width;
+      MetaDrawSpec *height;
+      MetaDrawSpec *tile_xoffset;
+      MetaDrawSpec *tile_yoffset;
+      MetaDrawSpec *tile_width;
+      MetaDrawSpec *tile_height;
     } tile;
     
   } data;
@@ -597,6 +663,21 @@ struct _MetaTheme
   MetaFrameStyleSet *style_sets_by_type[META_FRAME_TYPE_LAST];
 
   GdkPixbuf *fallback_icon, *fallback_mini_icon;
+
+  GQuark quark_width;
+  GQuark quark_height;
+  GQuark quark_object_width;
+  GQuark quark_object_height;
+  GQuark quark_left_width;
+  GQuark quark_right_width;
+  GQuark quark_top_height;
+  GQuark quark_bottom_height;
+  GQuark quark_mini_icon_width;
+  GQuark quark_mini_icon_height;
+  GQuark quark_icon_width;
+  GQuark quark_icon_height;
+  GQuark quark_title_width;
+  GQuark quark_title_height;
 };
 
 struct _MetaPositionExprEnv
@@ -643,16 +724,21 @@ void             meta_frame_layout_calc_geometry (const MetaFrameLayout  *layout
 gboolean         meta_frame_layout_validate      (const MetaFrameLayout *layout,
                                                   GError               **error);
 
-gboolean meta_parse_position_expression (const char                 *expr,
+gboolean meta_parse_position_expression (MetaDrawSpec               *spec,
                                          const MetaPositionExprEnv  *env,
                                          int                        *x_return,
                                          int                        *y_return,
                                          GError                    **err);
-gboolean meta_parse_size_expression     (const char                 *expr,
+gboolean meta_parse_size_expression     (MetaDrawSpec               *spec,
                                          const MetaPositionExprEnv  *env,
                                          int                        *val_return,
                                          GError                    **err);
 
+MetaDrawSpec* meta_draw_spec_new (MetaTheme  *theme,
+                                  const char *expr,
+                                  GError    **error);
+void          meta_draw_spec_free (MetaDrawSpec *spec);
+
 MetaColorSpec* meta_color_spec_new             (MetaColorSpecType  type);
 MetaColorSpec* meta_color_spec_new_from_string (const char        *str,
                                                 GError           **err);
@@ -833,9 +919,10 @@ gboolean meta_theme_lookup_color_constant (MetaTheme   *theme,
                                            const char  *name,
                                            char       **value);
 
-char*    meta_theme_replace_constants     (MetaTheme   *theme,
-                                           const char  *expr,
-                                           GError     **err);
+gboolean     meta_theme_replace_constants     (MetaTheme    *theme,
+                                               PosToken     *tokens,
+                                               int           n_tokens,
+                                               GError      **err);
 
 /* random stuff */
 
@@ -877,6 +964,7 @@ const char*           meta_image_fill_type_to_string   (MetaImageFillType      f
 
 guint meta_theme_earliest_version_with_button (MetaButtonType type);
 
+
 #define META_THEME_ALLOWS(theme, feature) (theme->format_version >= feature)
 
 /* What version of the theme file format were various features introduced in? */