[mutter] screen-cast-stream: Add API to transform relative coordinates

[Jonas Ådahl <jadahl src gnome org>]

commit 4d5e1f690dcf42997f09c1638ea96ae7a603baef
Author: Jonas Ådahl <jadahl gmail com>
Date:   Mon Jan 29 14:46:13 2018 +0800

    screen-cast-stream: Add API to transform relative coordinates
    
    Will be used to translate stream local coordinates to stage coordinates.

 src/backends/meta-screen-cast-monitor-stream.c | 19 +++++++++++++++++++
 src/backends/meta-screen-cast-stream.c         | 14 ++++++++++++++
 src/backends/meta-screen-cast-stream.h         | 11 +++++++++++
 3 files changed, 44 insertions(+)
---
diff --git a/src/backends/meta-screen-cast-monitor-stream.c b/src/backends/meta-screen-cast-monitor-stream.c
index 853090a43..df43f977c 100644
--- a/src/backends/meta-screen-cast-monitor-stream.c
+++ b/src/backends/meta-screen-cast-monitor-stream.c
@@ -176,6 +176,24 @@ meta_screen_cast_monitor_stream_set_parameters (MetaScreenCastStream *stream,
                                         logical_monitor_layout.height));
 }
 
+static void
+meta_screen_cast_monitor_stream_transform_position (MetaScreenCastStream *stream,
+                                                    double                stream_x,
+                                                    double                stream_y,
+                                                    double               *x,
+                                                    double               *y)
+{
+  MetaScreenCastMonitorStream *monitor_stream =
+    META_SCREEN_CAST_MONITOR_STREAM (stream);
+  MetaRectangle logical_monitor_layout;
+
+  logical_monitor_layout =
+    meta_logical_monitor_get_layout (monitor_stream->logical_monitor);
+
+  *x = logical_monitor_layout.x + stream_x;
+  *y = logical_monitor_layout.y + stream_y;
+}
+
 static void
 meta_screen_cast_monitor_stream_set_property (GObject      *object,
                                               guint         prop_id,
@@ -247,6 +265,7 @@ meta_screen_cast_monitor_stream_class_init (MetaScreenCastMonitorStreamClass *kl
 
   stream_class->create_src = meta_screen_cast_monitor_stream_create_src;
   stream_class->set_parameters = meta_screen_cast_monitor_stream_set_parameters;
+  stream_class->transform_position = meta_screen_cast_monitor_stream_transform_position;
 
   g_object_class_install_property (object_class,
                                    PROP_MONITOR,
diff --git a/src/backends/meta-screen-cast-stream.c b/src/backends/meta-screen-cast-stream.c
index 1c9613585..97ee4bfcf 100644
--- a/src/backends/meta-screen-cast-stream.c
+++ b/src/backends/meta-screen-cast-stream.c
@@ -136,6 +136,20 @@ meta_screen_cast_stream_get_object_path (MetaScreenCastStream *stream)
   return priv->object_path;
 }
 
+void
+meta_screen_cast_stream_transform_position (MetaScreenCastStream *stream,
+                                            double                stream_x,
+                                            double                stream_y,
+                                            double               *x,
+                                            double               *y)
+{
+  META_SCREEN_CAST_STREAM_GET_CLASS (stream)->transform_position (stream,
+                                                                  stream_x,
+                                                                  stream_y,
+                                                                  x,
+                                                                  y);
+}
+
 static void
 meta_screen_cast_stream_set_property (GObject      *object,
                                       guint         prop_id,
diff --git a/src/backends/meta-screen-cast-stream.h b/src/backends/meta-screen-cast-stream.h
index 36706ee7e..fd7930c4c 100644
--- a/src/backends/meta-screen-cast-stream.h
+++ b/src/backends/meta-screen-cast-stream.h
@@ -41,6 +41,11 @@ struct _MetaScreenCastStreamClass
                                             GError              **error);
   void (* set_parameters) (MetaScreenCastStream *stream,
                            GVariantBuilder      *parameters_builder);
+  void (* transform_position) (MetaScreenCastStream *stream,
+                               double                stream_x,
+                               double                stream_y,
+                               double               *x,
+                               double               *y);
 };
 
 gboolean meta_screen_cast_stream_start (MetaScreenCastStream *stream,
@@ -50,4 +55,10 @@ void meta_screen_cast_stream_close (MetaScreenCastStream *stream);
 
 char * meta_screen_cast_stream_get_object_path (MetaScreenCastStream *stream);
 
+void meta_screen_cast_stream_transform_position (MetaScreenCastStream *stream,
+                                                 double                stream_x,
+                                                 double                stream_y,
+                                                 double               *x,
+                                                 double               *y);
+
 #endif /* META_SCREEN_CAST_STREAM_H */