[ease] [editor] Added gradient angle support.

[Nate Stedman <natesm src gnome org>]

commit 89ce738c24541cfce9ef9d5a508a3f933f1138d2
Author: Nate Stedman <natesm gmail com>
Date:   Mon Jul 26 21:54:20 2010 -0400

    [editor] Added gradient angle support.

 data/ui/inspector-slide.ui         |    3 ++-
 src/ease-gradient.vala             |   23 ++++++++++++++++-------
 src/ease-inspector-slide-pane.vala |   21 +++++++++++++++++++++
 3 files changed, 39 insertions(+), 8 deletions(-)
---
diff --git a/data/ui/inspector-slide.ui b/data/ui/inspector-slide.ui
index cf0a756..92efe38 100644
--- a/data/ui/inspector-slide.ui
+++ b/data/ui/inspector-slide.ui
@@ -239,8 +239,10 @@
                   <object class="GtkHScale" id="hscale-angle">
                     <property name="visible">True</property>
                     <property name="can_focus">True</property>
+                    <property name="update_policy">discontinuous</property>
                     <property name="adjustment">adjustment-angle</property>
                     <property name="draw_value">False</property>
+                    <signal name="value_changed" handler="ease_inspector_slide_pane_on_set_angle"/>
                   </object>
                   <packing>
                     <property name="position">1</property>
@@ -310,6 +312,5 @@
     <property name="upper">6.2800000000000002</property>
     <property name="step_increment">0.10000000000000001</property>
     <property name="page_increment">1</property>
-    <property name="page_size">1</property>
   </object>
 </interface>
diff --git a/src/ease-gradient.vala b/src/ease-gradient.vala
index 3ddb1aa..4395e37 100644
--- a/src/ease-gradient.vala
+++ b/src/ease-gradient.vala
@@ -23,7 +23,7 @@ public class Ease.Gradient : GLib.Object
 	/**
 	 * The format string for converting gradients to strings.
 	 */
-	private const string STR = "%s%s%s%s%s%s";
+	private const string STR = "%s|%s|%s|%f";
 	
 	/**
 	 * The string placed between each color in a string representation.
@@ -153,10 +153,8 @@ public class Ease.Gradient : GLib.Object
 	 */
 	public string to_string()
 	{
-		return STR.printf(start.to_string(), SPLIT,
-		                  end.to_string(), SPLIT,
-		                  mode.to_string(), SPLIT,
-		                  angle.to_string());
+		return STR.printf(start.to_string(), end.to_string(),
+		                  mode.to_string(), angle);
 	}
 	
 	/**
@@ -192,18 +190,29 @@ public class Ease.Gradient : GLib.Object
 		cr.save();
 		cr.rectangle(0, 0, width, height);
 		
+		var x_orig = width / 2;
+		var y_orig = height / 2;
+		var dist_x = (int)(Math.cos(angle + Math.PI / 2) * y_orig);
+		var dist_y = (int)(Math.sin(angle + Math.PI / 2) * y_orig);
+		
 		Cairo.Pattern pattern;
 		switch (mode)
 		{
 			case GradientType.LINEAR:				
-				pattern = new Cairo.Pattern.linear(0, 0, 0, height);
+				pattern = new Cairo.Pattern.linear(x_orig - dist_x,
+				                                   y_orig - dist_y,
+				                                   x_orig + dist_x,
+				                                   y_orig + dist_y);
 				pattern.add_color_stop_rgba(0, start.red, start.green,
 						                    start.blue, start.alpha);
 				pattern.add_color_stop_rgba(1, end.red, end.green,
 						                    end.blue, end.alpha);
 				break;
 			case GradientType.LINEAR_MIRRORED:
-				pattern = new Cairo.Pattern.linear(0, 0, 0, height);
+				pattern = new Cairo.Pattern.linear(x_orig - dist_x,
+				                                   y_orig - dist_y,
+				                                   x_orig + dist_x,
+				                                   y_orig + dist_y);
 				pattern.add_color_stop_rgba(0, start.red, start.green,
 						                    start.blue, start.alpha);
 				pattern.add_color_stop_rgba(0.5, end.red, end.green,
diff --git a/src/ease-inspector-slide-pane.vala b/src/ease-inspector-slide-pane.vala
index 188f77f..abb333b 100644
--- a/src/ease-inspector-slide-pane.vala
+++ b/src/ease-inspector-slide-pane.vala
@@ -30,6 +30,7 @@ public class Ease.InspectorSlidePane : InspectorPane
 	private Gtk.VBox box_color;
 	private Gtk.VBox box_gradient;
 	private Gtk.VBox box_image;
+	private Gtk.HScale grad_angle;
 	
 	private Gtk.ColorButton bg_color;
 	private Gtk.ColorButton grad_color1;
@@ -70,6 +71,7 @@ public class Ease.InspectorSlidePane : InspectorPane
 			builder.get_object("button-image") as Gtk.FileChooserButton;
 		gradient_type =
 			builder.get_object("combo-gradient") as Gtk.ComboBox;
+		grad_angle = builder.get_object("hscale-angle") as Gtk.HScale;
 		
 		// set up the gradient type combobox
 		gradient_type.model = grad_store;
@@ -268,6 +270,23 @@ public class Ease.InspectorSlidePane : InspectorPane
 		emit_undo(action);
 	}
 	
+	[CCode (instance_pos = -1)]
+	public void on_set_angle(Gtk.Widget? sender)
+	{
+		var action = new UndoAction(slide.background_gradient, "angle");
+		slide.background_gradient.angle =
+			(sender as Gtk.HScale).adjustment.value;
+		undo(action);
+		
+		slide.changed(slide);
+		
+		var local = slide;
+		action.applied.connect((a) => {
+			local.changed(local);
+			if (local == slide) display_bg_ui(slide.background_type);
+		});
+	}
+	
 	protected override void slide_updated()
 	{
 		silence_undo = true;
@@ -323,6 +342,8 @@ public class Ease.InspectorSlidePane : InspectorPane
 				grad_color1.set_color(slide.background_gradient.start.gdk);
 				grad_color2.set_color(slide.background_gradient.end.gdk);
 				
+				grad_angle.adjustment.value = slide.background_gradient.angle;
+				
 				slide.changed(slide);
 				
 				break;