libsysprof-gtk: make accent fg/bg color available internally

This does more work than it should have to since we are reading the color
repeatedly, but it's still better than the data being stored per-instance.

src/libsysprof-gtk/sysprof-chart-layer-private.h

@@ -0,0 +1,30 @@
+/* sysprof-chart-layer-private.h
+ *
+ * Copyright 2023 Christian Hergert <chergert@redhat.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#include "sysprof-chart-layer.h"
+
+G_BEGIN_DECLS
+
+const GdkRGBA *_sysprof_chart_layer_get_accent_bg_color (void);
+const GdkRGBA *_sysprof_chart_layer_get_accent_fg_color (void);
+
+G_END_DECLS

src/libsysprof-gtk/sysprof-chart-layer.c

@@ -20,7 +20,7 @@
 
 #include "config.h"
 
-#include "sysprof-chart-layer.h"
+#include "sysprof-chart-layer-private.h"
 
 typedef struct
 {
@@ -36,6 +36,24 @@ enum {
 G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (SysprofChartLayer, sysprof_chart_layer, GTK_TYPE_WIDGET)
 
 static GParamSpec *properties [N_PROPS];
+static GdkRGBA accent_fg_color;
+static GdkRGBA accent_bg_color;
+
+static void
+sysprof_chart_layer_css_changed (GtkWidget         *widget,
+                                 GtkCssStyleChange *change)
+{
+G_GNUC_BEGIN_IGNORE_DEPRECATIONS
+  GtkStyleContext *style_context;
+
+  GTK_WIDGET_CLASS (sysprof_chart_layer_parent_class)->css_changed (widget, change);
+
+  style_context = gtk_widget_get_style_context (widget);
+
+  gtk_style_context_lookup_color (style_context, "accent_fg_color", &accent_fg_color);
+  gtk_style_context_lookup_color (style_context, "accent_bg_color", &accent_bg_color);
+G_GNUC_END_IGNORE_DEPRECATIONS
+}
 
 static void
 sysprof_chart_layer_dispose (GObject *object)
@@ -96,6 +114,8 @@ sysprof_chart_layer_class_init (SysprofChartLayerClass *klass)
   object_class->get_property = sysprof_chart_layer_get_property;
   object_class->set_property = sysprof_chart_layer_set_property;
 
+  widget_class->css_changed = sysprof_chart_layer_css_changed;
+
   properties[PROP_TITLE] =
     g_param_spec_string ("title", NULL, NULL,
                          NULL,
@@ -171,3 +191,15 @@ sysprof_chart_layer_lookup_item (SysprofChartLayer *self,
 
   return NULL;
 }
+
+const GdkRGBA *
+_sysprof_chart_layer_get_accent_bg_color (void)
+{
+  return &accent_bg_color;
+}
+
+const GdkRGBA *
+_sysprof_chart_layer_get_accent_fg_color (void)
+{
+  return &accent_fg_color;
+}

src/libsysprof-gtk/sysprof-column-layer.c

@@ -21,6 +21,7 @@
 #include "config.h"
 
 #include "sysprof-axis.h"
+#include "sysprof-chart-layer-private.h"
 #include "sysprof-column-layer.h"
 #include "sysprof-normalized-series.h"
 #include "sysprof-xy-layer-private.h"
@@ -28,8 +29,12 @@
 struct _SysprofColumnLayer
 {
   SysprofXYLayer parent_instance;
+
   GdkRGBA        color;
   GdkRGBA        hover_color;
+
+  guint          color_set : 1;
+  guint          hover_color_set : 1;
 };
 
 enum {
@@ -51,6 +56,7 @@ sysprof_column_layer_snapshot (GtkWidget   *widget,
   graphene_matrix_t flip_y;
   const float *x_values;
   const float *y_values;
+  const GdkRGBA *color;
   guint n_values;
   int width;
   int height;
@@ -66,6 +72,11 @@ sysprof_column_layer_snapshot (GtkWidget   *widget,
   if (width == 0 || height == 0 || n_values == 0 || self->color.alpha == 0)
     return;
 
+  if (self->color_set)
+    color = &self->color;
+  else
+    color = _sysprof_chart_layer_get_accent_bg_color ();
+
   gtk_snapshot_save (snapshot);
 
   graphene_matrix_init_from_2d (&flip_y, 1, 0, 0, -1, 0, height);
@@ -76,7 +87,7 @@ sysprof_column_layer_snapshot (GtkWidget   *widget,
       int line_height = ceilf (y_values[i] * height);
 
       gtk_snapshot_append_color (snapshot,
-                                 &self->color,
+                                 color,
                                  &GRAPHENE_RECT_INIT (x_values[i] * width,
                                                       0,
                                                       1,
@@ -255,8 +266,8 @@ sysprof_column_layer_class_init (SysprofColumnLayerClass *klass)
 static void
 sysprof_column_layer_init (SysprofColumnLayer *self)
 {
-  gdk_rgba_parse (&self->color, "#000");
-  gdk_rgba_parse (&self->hover_color, "#F00");
+  self->color = (GdkRGBA) {0,0,0,1};
+  self->hover_color = (GdkRGBA) {1,0,0,1};
 }
 
 SysprofChartLayer *
@@ -287,6 +298,7 @@ sysprof_column_layer_set_color (SysprofColumnLayer *self,
   if (!gdk_rgba_equal (&self->color, color))
     {
       self->color = *color;
+      self->color_set = color != &black;
 
       g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_COLOR]);
 
@@ -316,6 +328,7 @@ sysprof_column_layer_set_hover_color (SysprofColumnLayer *self,
   if (!gdk_rgba_equal (&self->hover_color, hover_color))
     {
       self->hover_color = *hover_color;
+      self->hover_color_set = hover_color != &red;
 
       g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_HOVER_COLOR]);
 

src/libsysprof-gtk/sysprof-line-layer.c

@@ -21,6 +21,7 @@
 
 #include "config.h"
 
+#include "sysprof-chart-layer-private.h"
 #include "sysprof-line-layer.h"
 #include "sysprof-xy-layer-private.h"
 
@@ -55,8 +56,6 @@ enum {
 };
 
 static GParamSpec *properties [N_PROPS];
-static GdkRGBA accent_bg_color;
-static GdkRGBA accent_fg_color;
 
 SysprofChartLayer *
 sysprof_line_layer_new (void)
@@ -71,7 +70,7 @@ sysprof_line_layer_snapshot (GtkWidget   *widget,
   SysprofLineLayer *self = (SysprofLineLayer *)widget;
   const float *x_values;
   const float *y_values;
-  GdkRGBA *color;
+  const GdkRGBA *color;
   cairo_t *cr;
   float first_x;
   float first_y;
@@ -95,7 +94,7 @@ sysprof_line_layer_snapshot (GtkWidget   *widget,
   if (self->color_set)
     color = &self->color;
   else
-    color = &accent_bg_color;
+    color = _sysprof_chart_layer_get_accent_bg_color ();
 
   cr = gtk_snapshot_append_cairo (snapshot, &GRAPHENE_RECT_INIT (0, 0, width, height));
 
@@ -163,22 +162,6 @@ sysprof_line_layer_snapshot (GtkWidget   *widget,
   cairo_destroy (cr);
 }
 
-static void
-sysprof_line_layer_css_changed (GtkWidget         *widget,
-                                GtkCssStyleChange *css_change)
-{
-G_GNUC_BEGIN_IGNORE_DEPRECATIONS
-  GtkStyleContext *style_context;
-
-  GTK_WIDGET_CLASS (sysprof_line_layer_parent_class)->css_changed (widget, css_change);
-
-  style_context = gtk_widget_get_style_context (widget);
-
-  gtk_style_context_lookup_color (style_context, "accent_fg_color", &accent_fg_color);
-  gtk_style_context_lookup_color (style_context, "accent_bg_color", &accent_bg_color);
-G_GNUC_END_IGNORE_DEPRECATIONS
-}
-
 static void
 sysprof_line_layer_get_property (GObject    *object,
                                  guint       prop_id,
@@ -259,7 +242,6 @@ sysprof_line_layer_class_init (SysprofLineLayerClass *klass)
   object_class->set_property = sysprof_line_layer_set_property;
 
   widget_class->snapshot = sysprof_line_layer_snapshot;
-  widget_class->css_changed = sysprof_line_layer_css_changed;
 
   properties[PROP_COLOR] =
     g_param_spec_boxed ("color", NULL, NULL,