[gtk/wip/chergert/glproto] add helper to create GdkGLTexture

[Christian Hergert <chergert src gnome org>]

commit 3206d3ac4ed4e99be1aedf1ad4352405506f3e93
Author: Christian Hergert <chergert redhat com>
Date:   Mon Feb 1 16:56:36 2021 -0800

    add helper to create GdkGLTexture
    
    this moves the code out of the renderer and into the driver were we can
    make the driver stop tracking the texture instance.

 gsk/next/gskgldriver.c        | 52 +++++++++++++++++++++++++++++++++++++++++++
 gsk/next/gskgldriverprivate.h |  2 ++
 2 files changed, 54 insertions(+)
---
diff --git a/gsk/next/gskgldriver.c b/gsk/next/gskgldriver.c
index c800ecce94..970de9db0e 100644
--- a/gsk/next/gskgldriver.c
+++ b/gsk/next/gskgldriver.c
@@ -41,6 +41,12 @@
 
 #define ATLAS_SIZE 512
 
+typedef struct _GskGLTextureState
+{
+  GdkGLContext *context;
+  GLuint        texture_id;
+} GskGLTextureState;
+
 G_DEFINE_TYPE (GskNextDriver, gsk_next_driver, G_TYPE_OBJECT)
 
 static guint
@@ -1275,3 +1281,49 @@ gsk_next_driver_release_texture_by_id (GskNextDriver *self,
   if ((texture = g_hash_table_lookup (self->textures, GUINT_TO_POINTER (texture_id))))
     gsk_next_driver_release_texture (self, texture);
 }
+
+
+static void
+create_texture_from_texture_destroy (gpointer data)
+{
+  GskGLTextureState *state = data;
+
+  g_assert (state != NULL);
+  g_assert (GDK_IS_GL_CONTEXT (state->context));
+
+  gdk_gl_context_make_current (state->context);
+  glDeleteTextures (1, &state->texture_id);
+  g_clear_object (&state->context);
+  g_slice_free (GskGLTextureState, state);
+}
+
+GdkTexture *
+gsk_next_driver_create_gdk_texture (GskNextDriver *self,
+                                    guint          texture_id)
+{
+  GskGLTextureState *state;
+  GskGLTexture *texture;
+
+  g_return_val_if_fail (GSK_IS_NEXT_DRIVER (self), NULL);
+  g_return_val_if_fail (self->command_queue != NULL, NULL);
+  g_return_val_if_fail (GDK_IS_GL_CONTEXT (self->command_queue->context), NULL);
+  g_return_val_if_fail (texture_id > 0, NULL);
+  g_return_val_if_fail (!g_hash_table_contains (self->texture_id_to_key, GUINT_TO_POINTER (texture_id)), 
NULL);
+
+  /* We must be tracking this texture_id already to use it */
+  if (!(texture = g_hash_table_lookup (self->textures, GUINT_TO_POINTER (texture_id))))
+    g_return_val_if_reached (NULL);
+
+  state = g_slice_new0 (GskGLTextureState);
+  state->texture_id = texture_id;
+  state->context = g_object_ref (self->command_queue->context);
+
+  g_hash_table_steal (self->textures, GUINT_TO_POINTER (texture_id));
+
+  return gdk_gl_texture_new (self->command_queue->context,
+                             texture_id,
+                             texture->width,
+                             texture->height,
+                             create_texture_from_texture_destroy,
+                             state);
+}
diff --git a/gsk/next/gskgldriverprivate.h b/gsk/next/gskgldriverprivate.h
index 824deae58a..61f88c9143 100644
--- a/gsk/next/gskgldriverprivate.h
+++ b/gsk/next/gskgldriverprivate.h
@@ -135,6 +135,8 @@ guint              gsk_next_driver_release_render_target (GskNextDriver        *
 void               gsk_next_driver_begin_frame           (GskNextDriver        *self,
                                                           GskGLCommandQueue    *command_queue);
 void               gsk_next_driver_end_frame             (GskNextDriver        *self);
+GdkTexture        *gsk_next_driver_create_gdk_texture    (GskNextDriver        *self,
+                                                          guint                 texture_id);
 guint              gsk_next_driver_lookup_texture        (GskNextDriver        *self,
                                                           const GskTextureKey  *key);
 void               gsk_next_driver_cache_texture         (GskNextDriver        *self,