[gnome-shell] Add shell-xfixes-cursor.[ch]

[Colin Walters <walters src gnome org>]

commit 80fc55b8eae947deefd5fd670c91bcb11d96f625
Author: Colin Walters <walters verbum org>
Date:   Tue May 11 15:03:11 2010 -0400

    Add shell-xfixes-cursor.[ch]
    
    Also missing somehow from the magnification commit.

 src/shell-xfixes-cursor.c |  385 +++++++++++++++++++++++++++++++++++++++++++++
 src/shell-xfixes-cursor.h |   33 ++++
 2 files changed, 418 insertions(+), 0 deletions(-)
---
diff --git a/src/shell-xfixes-cursor.c b/src/shell-xfixes-cursor.c
new file mode 100644
index 0000000..baf677c
--- /dev/null
+++ b/src/shell-xfixes-cursor.c
@@ -0,0 +1,385 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "shell-xfixes-cursor.h"
+
+#include <clutter/x11/clutter-x11.h>
+#include <X11/extensions/Xfixes.h>
+
+/**
+ * SECTION:ShellXFixesCursor
+ * short_description: Capture/manipulate system mouse cursor.
+ *
+ * The #ShellXFixesCursor object uses the XFixes extension to show/hide the
+ * the system mouse pointer, to grab its image as it changes, and emit a
+ * notification when its image changes.
+ */
+
+struct _ShellXFixesCursorClass
+{
+  GObjectClass parent_class;
+};
+
+struct _ShellXFixesCursor {
+  GObject parent;
+
+  ClutterStage *stage;
+
+  gboolean have_xfixes;
+  int xfixes_event_base;
+
+  gboolean is_showing;
+
+  CoglHandle *cursor_sprite;
+  int cursor_hot_x;
+  int cursor_hot_y;
+};
+
+static void xfixes_cursor_show        (ShellXFixesCursor *xfixes_cursor);
+static void xfixes_cursor_hide        (ShellXFixesCursor *xfixes_cursor);
+
+static void xfixes_cursor_set_stage   (ShellXFixesCursor *xfixes_cursor,
+                                       ClutterStage  *stage);
+
+static void xfixes_cursor_reset_image (ShellXFixesCursor *xfixes_cursor);
+
+enum {
+  PROP_0,
+  PROP_STAGE,
+};
+
+G_DEFINE_TYPE(ShellXFixesCursor, shell_xfixes_cursor, G_TYPE_OBJECT);
+
+enum {
+    CURSOR_CHANGED,
+    LAST_SIGNAL
+};
+
+static guint signals[LAST_SIGNAL] = { 0 };
+
+static void
+shell_xfixes_cursor_init (ShellXFixesCursor *xfixes_cursor)
+{
+  // (JS) Best (?) that can be assumed since XFixes doesn't provide a way of
+  // detecting if the system mouse cursor is showing or not.
+  xfixes_cursor->is_showing = TRUE;
+}
+
+static void
+shell_xfixes_cursor_finalize (GObject  *object)
+{
+  ShellXFixesCursor *xfixes_cursor = SHELL_XFIXES_CURSOR (object);
+
+  // Make sure the system cursor is showing before leaving the stage.
+  xfixes_cursor_show (xfixes_cursor);
+  xfixes_cursor_set_stage (xfixes_cursor, NULL);
+  if (xfixes_cursor->cursor_sprite != NULL)
+    cogl_handle_unref (xfixes_cursor->cursor_sprite);
+
+  G_OBJECT_CLASS (shell_xfixes_cursor_parent_class)->finalize (object);
+}
+
+static void
+xfixes_cursor_on_stage_destroy (ClutterActor  *actor,
+                                ShellXFixesCursor *xfixes_cursor)
+{
+  xfixes_cursor_set_stage (xfixes_cursor, NULL);
+}
+
+static ClutterX11FilterReturn
+xfixes_cursor_event_filter (XEvent        *xev,
+                            ClutterEvent  *cev,
+                            gpointer       data)
+{
+  ShellXFixesCursor *xfixes_cursor = data;
+
+  if (xev->xany.window != clutter_x11_get_stage_window (xfixes_cursor->stage))
+    return CLUTTER_X11_FILTER_CONTINUE;
+
+  if (xev->xany.type == xfixes_cursor->xfixes_event_base + XFixesCursorNotify)
+    {
+      XFixesCursorNotifyEvent *notify_event = (XFixesCursorNotifyEvent *)xev;
+      if (notify_event->subtype == XFixesDisplayCursorNotify)
+        xfixes_cursor_reset_image (xfixes_cursor);
+    }
+    return CLUTTER_X11_FILTER_CONTINUE;
+}
+
+static void
+xfixes_cursor_set_stage (ShellXFixesCursor *xfixes_cursor,
+                         ClutterStage  *stage)
+{
+  if (xfixes_cursor->stage == stage)
+    return;
+
+  if (xfixes_cursor->stage)
+    {
+      g_signal_handlers_disconnect_by_func (xfixes_cursor->stage,
+                                            (void *)xfixes_cursor_on_stage_destroy,
+                                            xfixes_cursor);
+
+      clutter_x11_remove_filter (xfixes_cursor_event_filter, xfixes_cursor);
+    }
+  xfixes_cursor->stage = stage;
+  if (xfixes_cursor->stage)
+    {
+      int error_base;
+
+      xfixes_cursor->stage = stage;
+      g_signal_connect (xfixes_cursor->stage, "destroy",
+                        G_CALLBACK (xfixes_cursor_on_stage_destroy), xfixes_cursor);
+
+      clutter_x11_add_filter (xfixes_cursor_event_filter, xfixes_cursor);
+
+      xfixes_cursor->have_xfixes = XFixesQueryExtension (clutter_x11_get_default_display (),
+                                                         &xfixes_cursor->xfixes_event_base,
+                                                         &error_base);
+      if (xfixes_cursor->have_xfixes)
+        XFixesSelectCursorInput (clutter_x11_get_default_display (),
+                                 clutter_x11_get_stage_window (stage),
+                                 XFixesDisplayCursorNotifyMask);
+
+      xfixes_cursor_reset_image (xfixes_cursor);
+    }
+}
+
+static void
+xfixes_cursor_show (ShellXFixesCursor *xfixes_cursor)
+{
+  int minor, major;
+  Display *xdisplay;
+  Window xwindow;
+
+  if (xfixes_cursor->is_showing == TRUE)
+      return;
+
+  if (!xfixes_cursor->have_xfixes || !xfixes_cursor->stage)
+      return;
+
+  xdisplay = clutter_x11_get_default_display ();
+  xwindow = clutter_x11_get_stage_window (xfixes_cursor->stage);
+  XFixesQueryVersion (xdisplay, &major, &minor);
+  if (major >= 4)
+    {
+      XFixesShowCursor (xdisplay, xwindow);
+      xfixes_cursor->is_showing = TRUE;
+    }
+}
+
+static void
+xfixes_cursor_hide (ShellXFixesCursor *xfixes_cursor)
+{
+  int minor, major;
+  Display *xdisplay;
+  Window xwindow;
+
+  if (xfixes_cursor->is_showing == FALSE)
+      return;
+
+  if (!xfixes_cursor->have_xfixes || !xfixes_cursor->stage)
+      return;
+
+  xdisplay = clutter_x11_get_default_display ();
+  xwindow = clutter_x11_get_stage_window (xfixes_cursor->stage);
+  XFixesQueryVersion (xdisplay, &major, &minor);
+  if (major >= 4)
+    {
+      XFixesHideCursor (xdisplay, xwindow);
+      xfixes_cursor->is_showing = FALSE;
+    }
+}
+
+static void
+xfixes_cursor_reset_image (ShellXFixesCursor *xfixes_cursor)
+{
+  XFixesCursorImage *cursor_image;
+  CoglHandle sprite = COGL_INVALID_HANDLE;
+
+  if (!xfixes_cursor->have_xfixes)
+    return;
+
+  cursor_image = XFixesGetCursorImage (clutter_x11_get_default_display ());
+  sprite = cogl_texture_new_from_data (cursor_image->width,
+                                       cursor_image->height,
+                                       COGL_TEXTURE_NONE,
+#if G_BYTE_ORDER == G_LITTLE_ENDIAN
+                                       COGL_PIXEL_FORMAT_BGRA_8888_PRE,
+#else
+                                       COGL_PIXEL_FORMAT_ARGB_8888_PRE,
+#endif
+                                       COGL_PIXEL_FORMAT_ANY,
+                                       cursor_image->width * 4, /* stride */
+                                       (const guint8 *) cursor_image->pixels);
+  if (sprite != COGL_INVALID_HANDLE)
+    {
+      if (xfixes_cursor->cursor_sprite != NULL)
+        cogl_handle_unref (xfixes_cursor->cursor_sprite);
+
+      xfixes_cursor->cursor_sprite = sprite;
+      xfixes_cursor->cursor_hot_x = cursor_image->xhot;
+      xfixes_cursor->cursor_hot_y = cursor_image->yhot;
+      g_signal_emit (xfixes_cursor, signals[CURSOR_CHANGED], 0);
+    }
+}
+
+static void
+shell_xfixes_cursor_set_property (GObject      *object,
+                                 guint         prop_id,
+                                 const GValue *value,
+                                 GParamSpec   *pspec)
+{
+  ShellXFixesCursor *xfixes_cursor = SHELL_XFIXES_CURSOR (object);
+
+  switch (prop_id)
+    {
+    case PROP_STAGE:
+      xfixes_cursor_set_stage (xfixes_cursor, g_value_get_object (value));
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+shell_xfixes_cursor_get_property (GObject         *object,
+                             guint            prop_id,
+                             GValue          *value,
+                             GParamSpec      *pspec)
+{
+  ShellXFixesCursor *xfixes_cursor = SHELL_XFIXES_CURSOR (object);
+
+  switch (prop_id)
+    {
+    case PROP_STAGE:
+      g_value_set_object (value, G_OBJECT (xfixes_cursor->stage));
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+shell_xfixes_cursor_class_init (ShellXFixesCursorClass *klass)
+{
+  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+
+  gobject_class->finalize = shell_xfixes_cursor_finalize;
+
+  signals[CURSOR_CHANGED] = g_signal_new ("cursor-change",
+                                       G_TYPE_FROM_CLASS (klass),
+                                       G_SIGNAL_RUN_LAST,
+                                       0,
+                                       NULL, NULL,
+                                       g_cclosure_marshal_VOID__VOID,
+                                       G_TYPE_NONE, 0);
+
+  gobject_class->get_property = shell_xfixes_cursor_get_property;
+  gobject_class->set_property = shell_xfixes_cursor_set_property;
+
+  g_object_class_install_property (gobject_class,
+                                   PROP_STAGE,
+                                   g_param_spec_object ("stage",
+                                                        "Stage",
+                                                        "Stage for mouse cursor",
+                                                        CLUTTER_TYPE_STAGE,
+                                                        G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
+}
+
+/**
+ * shell_xfixes_cursor_get_default:
+ *
+ * Return value: (transfer none): The global #ShellXFixesCursor singleton
+ */
+ShellXFixesCursor *
+shell_xfixes_cursor_get_default ()
+{
+  static ShellXFixesCursor *instance = NULL;
+
+  if (instance == NULL)
+    instance = g_object_new (SHELL_TYPE_XFIXES_CURSOR,
+                             "stage", clutter_stage_get_default (),
+                             NULL);
+
+  return instance;
+}
+
+/**
+ * shell_xfixes_cursor_hide:
+ * @xfixes_cursor: the #ShellXFixesCursor
+ *
+ * Hide the system mouse cursor.
+ */
+void
+shell_xfixes_cursor_hide (ShellXFixesCursor *xfixes_cursor)
+{
+  g_return_if_fail (SHELL_IS_XFIXES_CURSOR (xfixes_cursor));
+
+  xfixes_cursor_hide (xfixes_cursor);
+}
+
+/**
+ * shell_xfixes_cursor_show:
+ * @xfixes_cursor: the #ShellXFixesCursor
+ *
+ * Show the system mouse cursor to show
+ */
+void
+shell_xfixes_cursor_show (ShellXFixesCursor *xfixes_cursor)
+{
+  g_return_if_fail (SHELL_IS_XFIXES_CURSOR (xfixes_cursor));
+
+  xfixes_cursor_show (xfixes_cursor);
+}
+
+/**
+ * shell_xfixes_cursor_update_texture_image:
+ * @xfixes_cursor:  the #ShellXFixesCursor
+ * @texture:        ClutterTexture to update with the current sprite image.
+ */
+void
+shell_xfixes_cursor_update_texture_image (ShellXFixesCursor *xfixes_cursor,
+                                          ClutterTexture *texture)
+{
+    CoglHandle *old_sprite;
+    g_return_if_fail (SHELL_IS_XFIXES_CURSOR (xfixes_cursor));
+
+    if (texture == NULL)
+        return;
+
+    old_sprite = clutter_texture_get_cogl_texture (texture);
+    if (xfixes_cursor->cursor_sprite == old_sprite)
+        return;
+
+    clutter_texture_set_cogl_texture (texture, xfixes_cursor->cursor_sprite);
+}
+
+/**
+ * shell_xfixes_cursor_get_hot_x:
+ * @xfixes_cursor: the #ShellXFixesCursor
+ *
+ * Returns: the current mouse cursor's hot x-coordinate.
+ */
+int
+shell_xfixes_cursor_get_hot_x (ShellXFixesCursor *xfixes_cursor)
+{
+  g_return_val_if_fail (SHELL_IS_XFIXES_CURSOR (xfixes_cursor), 0);
+
+  return xfixes_cursor->cursor_hot_x;
+}
+
+/**
+ * shell_xfixes_cursor_get_hot_y:
+ * @xfixes_cursor: the #ShellXFixesCursor
+ *
+ * Returns: the current mouse cursor's hot y-coordinate.
+ */
+int
+shell_xfixes_cursor_get_hot_y (ShellXFixesCursor *xfixes_cursor)
+{
+  g_return_val_if_fail (SHELL_IS_XFIXES_CURSOR (xfixes_cursor), 0);
+
+  return xfixes_cursor->cursor_hot_y;
+}
diff --git a/src/shell-xfixes-cursor.h b/src/shell-xfixes-cursor.h
new file mode 100644
index 0000000..28af3d1
--- /dev/null
+++ b/src/shell-xfixes-cursor.h
@@ -0,0 +1,33 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+#ifndef __SHELL_XFIXES_CURSOR_H__
+#define __SHELL_XFIXES_CURSOR_H__
+
+#include <clutter/clutter.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+
+G_BEGIN_DECLS
+
+typedef struct _ShellXFixesCursor        ShellXFixesCursor;
+typedef struct _ShellXFixesCursorClass   ShellXFixesCursorClass;
+
+#define SHELL_TYPE_XFIXES_CURSOR             (shell_xfixes_cursor_get_type ())
+#define SHELL_XFIXES_CURSOR(object)          (G_TYPE_CHECK_INSTANCE_CAST ((object), SHELL_TYPE_XFIXES_CURSOR, ShellXFixesCursor))
+#define SHELL_XFIXES_CURSOR_CLASS(klass)     (G_TYPE_CHECK_CLASS_CAST ((klass), SHELL_TYPE_XFIXES_CURSOR, ShellXFixesCursorClass))
+#define SHELL_IS_XFIXES_CURSOR(object)       (G_TYPE_CHECK_INSTANCE_TYPE ((object), SHELL_TYPE_XFIXES_CURSOR))
+#define SHELL_IS_XFIXES_CURSOR_CLASS(klass)  (G_TYPE_CHECK_CLASS_TYPE ((klass), SHELL_TYPE_XFIXES_CURSOR))
+#define SHELL_XFIXES_CURSOR_GET_CLASS(obj)   (G_TYPE_INSTANCE_GET_CLASS ((obj), SHELL_TYPE_XFIXES_CURSOR, ShellXFixesCursorClass))
+
+GType               shell_xfixes_cursor_get_type     (void) G_GNUC_CONST;
+
+ShellXFixesCursor   *shell_xfixes_cursor_get_default (void);
+
+void                shell_xfixes_cursor_show (ShellXFixesCursor *xfixes_cursor);
+void                shell_xfixes_cursor_hide (ShellXFixesCursor *xfixes_cursor);
+int                 shell_xfixes_cursor_get_hot_x (ShellXFixesCursor *xfixes_cursor);
+int                 shell_xfixes_cursor_get_hot_y (ShellXFixesCursor *xfixes_cursor);
+void                shell_xfixes_cursor_update_texture_image (ShellXFixesCursor *xfixes_cursor,
+                                                              ClutterTexture *texture);
+
+G_END_DECLS
+
+#endif /* __SHELL_XFIXES_CURSOR_H__ */