cssshadowvalue: Treat one shadow like multiple shadows

If we create a GtkCssShadowsValue for just one shadow, just return that
show value instead and allow calls on GtkCssShadowsValue API on one
shadow. That saves us around 480 GtkCssShadowsValue instances in the
widget factory.

css value stats before:

GtkCssColorValue: 1452
GtkCssFilterValue: 3
GtkCssRgbaValue: 1092
GtkCssShadowValue: 708
GtkCssEaseValue: 33
GtkCssBorderValue: 2
GtkCssTransformValue: 11
GtkCssDimensionValue: 882
GtkCssShadowsValue: 584
GtkCssBgSizeValue: 23
GtkCssIdentValue: 25
GtkCssPositionValue: 81
GtkCssArrayValue: 143
GtkCssStringValue: 33
GtkCssPaletteValue: 29
GtkCssImageValue: 2765
SUM: 7872

and after:

GtkCssShadowsValue: 107
GtkCssBgSizeValue: 23
GtkCssIdentValue: 25
GtkCssPositionValue: 81
GtkCssArrayValue: 143
GtkCssStringValue: 33
GtkCssPaletteValue: 29
GtkCssImageValue: 2764
GtkCssColorValue: 1452
GtkCssFilterValue: 3
GtkCssRgbaValue: 1092
GtkCssShadowValue: 708
GtkCssEaseValue: 33
GtkCssBorderValue: 2
GtkCssTransformValue: 11
GtkCssDimensionValue: 883
SUM: 7395

7872 to 7395 is a 477 reduction (6.0%)

3 files changed, 64 insertions, 4 deletions

diff --git a/gtk/gtkcssshadowsvalue.c b/gtk/gtkcssshadowsvalue.c
index 60e3a548ec..2e09dae683 100644
--- a/gtk/gtkcssshadowsvalue.c
+++ b/gtk/gtkcssshadowsvalue.c
@@ -223,14 +223,17 @@ gtk_css_shadows_value_new (GtkCssValue **values,
                            guint         len)
 {
   GtkCssValue *result;
-           
+
   g_return_val_if_fail (values != NULL, NULL);
   g_return_val_if_fail (len > 0, NULL);
-         
+
+  if (len == 1)
+    return values[0];
+
   result = _gtk_css_value_alloc (&GTK_CSS_VALUE_SHADOWS, sizeof (GtkCssValue) + sizeof (GtkCssValue *) * (len - 1));
   result->len = len;
   memcpy (&result->values[0], values, sizeof (GtkCssValue *) * len);
-            
+
   return result;
 }
 
@@ -267,6 +270,9 @@ _gtk_css_shadows_value_parse (GtkCssParser *parser,
 gboolean
 _gtk_css_shadows_value_is_none (const GtkCssValue *shadows)
 {
+  if (gtk_css_shadow_value_is_shadow (shadows))
+    return FALSE;
+
   g_return_val_if_fail (shadows->class == &GTK_CSS_VALUE_SHADOWS, TRUE);
 
   return shadows->len == 0;
@@ -275,6 +281,9 @@ _gtk_css_shadows_value_is_none (const GtkCssValue *shadows)
 gsize
 gtk_css_shadows_value_get_n_shadows (const GtkCssValue *shadows)
 {
+  if (gtk_css_shadow_value_is_shadow (shadows))
+    return 1;
+
   return shadows->len;
 }
 
@@ -284,6 +293,12 @@ gtk_css_shadows_value_get_shadows (const GtkCssValue  *shadows,
 {
   guint i;
 
+  if (gtk_css_shadow_value_is_shadow (shadows))
+    {
+      gtk_css_shadow_value_get_shadow (shadows, &out_shadows[0]);
+      return;
+    }
+
   for (i = 0; i < shadows->len; i++)
     gtk_css_shadow_value_get_shadow (shadows->values[i], &out_shadows[i]);
 }
@@ -295,6 +310,14 @@ gtk_css_shadows_value_snapshot_outset (const GtkCssValue   *shadows,
 {
   guint i;
 
+  if (gtk_css_shadow_value_is_shadow (shadows))
+    {
+      if (!_gtk_css_shadow_value_get_inset (shadows))
+        gtk_css_shadow_value_snapshot_outset (shadows, snapshot, border_box);
+
+      return;
+    }
+
   g_return_if_fail (shadows->class == &GTK_CSS_VALUE_SHADOWS);
 
   for (i = 0; i < shadows->len; i++)
@@ -313,6 +336,14 @@ gtk_css_shadows_value_snapshot_inset (const GtkCssValue   *shadows,
 {
   guint i;
 
+  if (gtk_css_shadow_value_is_shadow (shadows))
+    {
+      if (_gtk_css_shadow_value_get_inset (shadows))
+        gtk_css_shadow_value_snapshot_outset (shadows, snapshot, padding_box);
+
+      return;
+    }
+
   g_return_if_fail (shadows->class == &GTK_CSS_VALUE_SHADOWS);
 
   for (i = 0; i < shadows->len; i++)
@@ -332,6 +363,15 @@ _gtk_css_shadows_value_get_extents (const GtkCssValue *shadows,
   GtkBorder b = { 0 }, sb;
   const GtkCssValue *shadow;
 
+  if (gtk_css_shadow_value_is_shadow (shadows))
+    {
+      if (!_gtk_css_shadow_value_get_inset (shadows))
+        gtk_css_shadow_value_get_extents (shadows, &b);
+
+      *border = b;
+      return;
+    }
+
   g_return_if_fail (shadows->class == &GTK_CSS_VALUE_SHADOWS);
 
   for (i = 0; i < shadows->len; i++)
@@ -356,9 +396,22 @@ gboolean
 gtk_css_shadows_value_push_snapshot (const GtkCssValue *value,
                                      GtkSnapshot       *snapshot)
 {
-  gboolean need_shadow = FALSE;
+  gboolean need_shadow;
   int i;
 
+  if (gtk_css_shadow_value_is_shadow (value))
+    {
+      GskShadow shadow;
+
+      if (!gtk_css_shadow_value_is_clear (value))
+        return FALSE;
+
+      gtk_css_shadow_value_get_shadow (value, &shadow);
+      gtk_snapshot_push_shadow (snapshot, &shadow, 1);
+      return TRUE;
+    }
+
+  need_shadow = FALSE;
   for (i = 0; i < value->len; i++)
     {
       if (!gtk_css_shadow_value_is_clear (value->values[i]))
diff --git a/gtk/gtkcssshadowvalue.c b/gtk/gtkcssshadowvalue.c
index 79a2950b8e..9f44d5f0b1 100644
--- a/gtk/gtkcssshadowvalue.c
+++ b/gtk/gtkcssshadowvalue.c
@@ -473,3 +473,8 @@ gtk_css_shadow_value_is_clear (const GtkCssValue *shadow)
   return gdk_rgba_is_clear (_gtk_css_rgba_value_get_rgba (shadow->color));
 }
 
+gboolean
+gtk_css_shadow_value_is_shadow (const GtkCssValue *maybe_shadow)
+{
+  return maybe_shadow->class == &GTK_CSS_VALUE_SHADOW;
+}
diff --git a/gtk/gtkcssshadowvalueprivate.h b/gtk/gtkcssshadowvalueprivate.h
index c2f66f0d72..b817dc61b1 100644
--- a/gtk/gtkcssshadowvalueprivate.h
+++ b/gtk/gtkcssshadowvalueprivate.h
@@ -52,6 +52,8 @@ void            gtk_css_shadow_value_snapshot_inset   (const GtkCssValue
 
 gboolean        gtk_css_shadow_value_is_clear         (const GtkCssValue        *shadow);
 
+gboolean        gtk_css_shadow_value_is_shadow        (const GtkCssValue        *maybe_shadow);
+
 G_END_DECLS
 
 #endif /* __GTK_SHADOW_H__ */