[Pixman] [PATCH] demo/scale: Add a spin button to set the number of subsample bits

[Søren Sandmann]

From: Søren Sandmann Pedersen <ssp at redhat.com>

For large upscalings the level of subsampling for the filter has a
quite visible effect, so make it settable in the UI so that people can
experiment with various values.
---
 demos/scale.c  | 16 +++++++++++++++-
 demos/scale.ui | 30 ++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/demos/scale.c b/demos/scale.c
index 9100ff7..676919b 100644
--- a/demos/scale.c
+++ b/demos/scale.c
@@ -39,6 +39,7 @@ typedef struct
     GtkAdjustment *     scale_x_adjustment;
     GtkAdjustment *     scale_y_adjustment;
     GtkAdjustment *     rotate_adjustment;
+    GtkAdjustment *	subsample_adjustment;
     int                 scaled_width;
     int                 scaled_height;
 } app_t;
@@ -182,6 +183,16 @@ to_scale (double v)
     return pow (1.15, v);
 }
 
+static int
+get_subsample (app_t *app)
+{
+    GtkAdjustment *adjustment =
+	GTK_ADJUSTMENT (gtk_builder_get_object (
+			    app->builder, "subsample_adjustment"));
+
+    return gtk_adjustment_get_value (adjustment);
+}
+
 static void
 rescale (GtkWidget *may_be_null, app_t *app)
 {
@@ -236,7 +247,7 @@ rescale (GtkWidget *may_be_null, app_t *app)
 	get_value (app, filters, "reconstruct_y_combo_box"),
 	get_value (app, filters, "sample_x_combo_box"),
 	get_value (app, filters, "sample_y_combo_box"),
-        4, 4);
+        get_subsample (app), get_subsample (app));
 
     pixman_image_set_filter (app->original, PIXMAN_FILTER_SEPARABLE_CONVOLUTION, params, n_params);
 
@@ -360,10 +371,13 @@ app_new (pixman_image_t *original)
         GTK_ADJUSTMENT (gtk_builder_get_object (app->builder, "scale_y_adjustment"));
     app->rotate_adjustment =
         GTK_ADJUSTMENT (gtk_builder_get_object (app->builder, "rotate_adjustment"));
+    app->subsample_adjustment =
+	GTK_ADJUSTMENT (gtk_builder_get_object (app->builder, "subsample_adjustment"));
 
     g_signal_connect (app->scale_x_adjustment, "value_changed", G_CALLBACK (rescale), app);
     g_signal_connect (app->scale_y_adjustment, "value_changed", G_CALLBACK (rescale), app);
     g_signal_connect (app->rotate_adjustment, "value_changed", G_CALLBACK (rescale), app);
+    g_signal_connect (app->subsample_adjustment, "value_changed", G_CALLBACK (rescale), app);
     
     widget = get_widget (app, "scale_x_scale");
     gtk_scale_add_mark (GTK_SCALE (widget), 0.0, GTK_POS_LEFT, NULL);
diff --git a/demos/scale.ui b/demos/scale.ui
index f7c0c80..b3450d3 100644
--- a/demos/scale.ui
+++ b/demos/scale.ui
@@ -23,6 +23,14 @@
     <property name="page_increment">10</property>
     <property name="page_size">10</property>
   </object>
+  <object class="GtkAdjustment" id="subsample_adjustment">
+    <property name="lower">1</property>
+    <property name="upper">12</property>
+    <property name="step_increment">1</property>
+    <property name="page_increment">1</property>
+    <property name="page_size">0</property>
+    <property name="value">4</property>
+  </object>
   <object class="GtkWindow" id="main">
     <child>
       <object class="GtkHBox" id="u">
@@ -51,6 +59,7 @@
         <child>
           <object class="GtkVBox" id="box1">
             <property name="visible">True</property>
+	    <property name="spacing">12</property>
             <child>
               <object class="GtkHBox" id="box2">
                 <property name="visible">True</property>
@@ -234,6 +243,17 @@
                       </packing>
                     </child>
                     <child>
+                      <object class="GtkLabel" id="label9">
+                        <property name="visible">True</property>
+                        <property name="xalign">1</property>
+                        <property name="label" translatable="yes"><b>Subsample:</b></property>
+                        <property name="use_markup">True</property>
+                      </object>
+                      <packing>
+                        <property name="top_attach">5</property>
+                      </packing>
+                    </child>
+                    <child>
                       <object class="GtkComboBox" id="reconstruct_x_combo_box">
                         <property name="visible">True</property>
                       </object>
@@ -277,6 +297,16 @@
                         <property name="top_attach">4</property>
                       </packing>
                     </child>
+                    <child>
+                      <object class="GtkSpinButton" id="subsample_spin_button">
+                        <property name="visible">True</property>
+			<property name="adjustment">subsample_adjustment</property>
+                      </object>
+                      <packing>
+                        <property name="left_attach">1</property>
+                        <property name="top_attach">5</property>
+                      </packing>
+                    </child>
                   </object>
                   <packing>
                     <property name="expand">False</property>
-- 
1.7.11.7