[gtk/wip/otte/nodeeditor2: 48/57] rendernode: Parse and print blend nodes properly

[Benjamin Otte <otte src gnome org>]

commit b4f5baf4fa031a2ba8d7aef0bf9215c513995985
Author: Benjamin Otte <otte redhat com>
Date:   Sat Apr 27 09:03:51 2019 +0200

    rendernode: Parse and print blend nodes properly

 gsk/gskrendernodeparser.c                     | 93 +++++++++++++++++++++++++--
 testsuite/gsk/meson.build                     |  3 +-
 testsuite/gsk/serializedeserialize/blend.node | 16 +++++
 3 files changed, 107 insertions(+), 5 deletions(-)
---
diff --git a/gsk/gskrendernodeparser.c b/gsk/gskrendernodeparser.c
index 9ebf4aab24..ea640c01e8 100644
--- a/gsk/gskrendernodeparser.c
+++ b/gsk/gskrendernodeparser.c
@@ -374,6 +374,49 @@ parse_shadows (GtkCssParser *parser,
   return parse_semicolon (parser);
 }
 
+static const struct
+{
+  GskBlendMode mode;
+  const char *name;
+} blend_modes[] = {
+  { GSK_BLEND_MODE_DEFAULT, "normal" },
+  { GSK_BLEND_MODE_MULTIPLY, "multiply" },
+  { GSK_BLEND_MODE_SCREEN, "screen" },
+  { GSK_BLEND_MODE_OVERLAY, "overlay" },
+  { GSK_BLEND_MODE_DARKEN, "darken" },
+  { GSK_BLEND_MODE_LIGHTEN, "lighten" },
+  { GSK_BLEND_MODE_COLOR_DODGE, "color-dodge" },
+  { GSK_BLEND_MODE_COLOR_BURN, "color-burn" },
+  { GSK_BLEND_MODE_HARD_LIGHT, "hard-light" },
+  { GSK_BLEND_MODE_SOFT_LIGHT, "soft-light" },
+  { GSK_BLEND_MODE_DIFFERENCE, "difference" },
+  { GSK_BLEND_MODE_EXCLUSION, "exclusion" },
+  { GSK_BLEND_MODE_COLOR, "color" },
+  { GSK_BLEND_MODE_HUE, "hue" },
+  { GSK_BLEND_MODE_SATURATION, "saturation" },
+  { GSK_BLEND_MODE_LUMINOSITY, "luminosity" }
+};
+
+static gboolean
+parse_blend_mode (GtkCssParser *parser,
+                  gpointer      out_mode)
+{
+  guint i;
+
+  for (i = 0; i < G_N_ELEMENTS (blend_modes); i++)
+    {
+      if (gtk_css_parser_try_ident (parser, blend_modes[i].name))
+        {
+          if (!parse_semicolon (parser))
+            return FALSE;
+          *(GskBlendMode *) out_mode = blend_modes[i].mode;
+          return TRUE;
+        }
+    }
+
+  return FALSE;
+}
+
 static gboolean
 parse_font (GtkCssParser *parser,
             gpointer      out_font)
@@ -827,6 +870,39 @@ parse_cross_fade_node (GtkCssParser *parser)
   return result;
 }
 
+static GskRenderNode *
+parse_blend_node (GtkCssParser *parser)
+{
+  GskRenderNode *bottom = NULL;
+  GskRenderNode *top = NULL;
+  GskBlendMode mode = GSK_BLEND_MODE_DEFAULT;
+  const Declaration declarations[] = {
+    { "mode", parse_blend_mode, &mode },
+    { "bottom", parse_node, &bottom },
+    { "top", parse_node, &top },
+  };
+  GskRenderNode *result;
+
+  parse_declarations (parser, declarations, G_N_ELEMENTS(declarations));
+  if (bottom == NULL || top == NULL)
+    {
+      if (bottom == NULL)
+        gtk_css_parser_error_syntax (parser, "Missing \"bottom\" property definition");
+      if (top == NULL)
+        gtk_css_parser_error_syntax (parser, "Missing \"top\" property definition");
+      g_clear_pointer (&bottom, gsk_render_node_unref);
+      g_clear_pointer (&top, gsk_render_node_unref);
+      return NULL;
+    }
+
+  result = gsk_blend_node_new (bottom, top, mode);
+
+  gsk_render_node_unref (bottom);
+  gsk_render_node_unref (top);
+
+  return result;
+}
+
 static GskRenderNode *
 parse_text_node (GtkCssParser *parser)
 {
@@ -1013,9 +1089,9 @@ parse_node (GtkCssParser *parser,
     { "cross-fade", parse_cross_fade_node },
     { "text", parse_text_node },
     { "blur", parse_blur_node },
-    { "debug", parse_debug_node }
-#if 0
+    { "debug", parse_debug_node },
     { "blend", parse_blend_node },
+#if 0
     { "repeat", parse_repeat_node },
     { "cairo", parse_cairo_node },
 #endif
@@ -1737,11 +1813,20 @@ render_node_print (Printer       *p,
 
     case GSK_BLEND_NODE:
       {
+        GskBlendMode mode = gsk_blend_node_get_blend_mode (node);
+        guint i;
+
         start_node (p, "blend");
 
         _indent (p);
-        /* TODO: (de)serialize enums! */
-        g_string_append_printf (p->str, "mode = %d\n", gsk_blend_node_get_blend_mode (node));
+        for (i = 0; i < G_N_ELEMENTS (blend_modes); i++)
+          {
+            if (blend_modes[i].mode == mode)
+              {
+                g_string_append_printf (p->str, "mode: %s;\n", blend_modes[i].name);
+                break;
+              }
+          }
         append_node_param (p, "top", gsk_blend_node_get_top_child (node));
         append_node_param (p, "bottom", gsk_blend_node_get_bottom_child (node));
 
diff --git a/testsuite/gsk/meson.build b/testsuite/gsk/meson.build
index c89594afe1..6223866089 100644
--- a/testsuite/gsk/meson.build
+++ b/testsuite/gsk/meson.build
@@ -85,8 +85,9 @@ foreach test : node_parser_tests
 endforeach
 
 serialize_deserialize_tests = [
-  'color',
+  'blend',
   'border',
+  'color',
   'shadow',
   'testswitch',
   'widgetfactory',
diff --git a/testsuite/gsk/serializedeserialize/blend.node b/testsuite/gsk/serializedeserialize/blend.node
new file mode 100644
index 0000000000..0b228ade85
--- /dev/null
+++ b/testsuite/gsk/serializedeserialize/blend.node
@@ -0,0 +1,16 @@
+blend {
+  bottom: container { }
+  top: container { }
+}
+
+blend {
+  top: container { }
+  mode: color-dodge;
+  bottom: container { }
+}
+
+blend {
+  top: color { }
+  bottom: color { }
+  mode: difference;
+}