glfilter: remove display_init/reset

They are mirrors of GstGLBaseFilter's gl_start() and gl_stop() virtual methods
so use them instead.

ext/gl/gstgldifferencematte.c

@@ -53,6 +53,7 @@ GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
 #define DEBUG_INIT \
   GST_DEBUG_CATEGORY_INIT (gst_gl_differencematte_debug, "gldifferencematte", 0, "gldifferencematte element");
 
+#define gst_gl_differencematte_parent_class parent_class
 G_DEFINE_TYPE_WITH_CODE (GstGLDifferenceMatte, gst_gl_differencematte,
     GST_TYPE_GL_FILTER, DEBUG_INIT);
 
@@ -74,16 +75,20 @@ enum
 
 
 /* init resources that need a gl context */
-static void
+static gboolean
-gst_gl_differencematte_init_gl_resources (GstGLFilter * filter)
+gst_gl_differencematte_gl_start (GstGLBaseFilter * base_filter)
 {
-  GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (filter);
+  GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (base_filter);
-  GstGLContext *context = GST_GL_BASE_FILTER (filter)->context;
+  GstGLFilter *filter = GST_GL_FILTER (base_filter);
+  GstGLContext *context = base_filter->context;
   GstGLBaseMemoryAllocator *tex_alloc;
   GstGLAllocationParams *params;
   GError *error = NULL;
   gint i;
 
+  if (!GST_GL_BASE_FILTER_CLASS (parent_class)->gl_start (base_filter))
+    return FALSE;
+
   tex_alloc = (GstGLBaseMemoryAllocator *)
       gst_gl_memory_allocator_get_default (context);
   params =
@@ -101,7 +106,7 @@ gst_gl_differencematte_init_gl_resources (GstGLFilter * filter)
           gst_gl_shader_new_default (context, &error))) {
     GST_ELEMENT_ERROR (differencematte, RESOURCE, NOT_FOUND, ("%s",
             "Failed to compile identity shader"), ("%s", error->message));
-    return;
+    return FALSE;
   }
 
   if (!(differencematte->shader[0] =
@@ -113,7 +118,7 @@ gst_gl_differencematte_init_gl_resources (GstGLFilter * filter)
                   difference_fragment_source), NULL))) {
     GST_ELEMENT_ERROR (differencematte, RESOURCE, NOT_FOUND, ("%s",
             "Failed to compile difference shader"), ("%s", error->message));
-    return;
+    return FALSE;
   }
 
   if (!(differencematte->shader[1] =
@@ -125,7 +130,7 @@ gst_gl_differencematte_init_gl_resources (GstGLFilter * filter)
                   hconv7_fragment_source_gles2), NULL))) {
     GST_ELEMENT_ERROR (differencematte, RESOURCE, NOT_FOUND, ("%s",
             "Failed to compile convolution shader"), ("%s", error->message));
-    return;
+    return FALSE;
   }
 
   if (!(differencematte->shader[2] =
@@ -137,7 +142,7 @@ gst_gl_differencematte_init_gl_resources (GstGLFilter * filter)
                   vconv7_fragment_source_gles2), NULL))) {
     GST_ELEMENT_ERROR (differencematte, RESOURCE, NOT_FOUND, ("%s",
             "Failed to compile convolution shader"), ("%s", error->message));
-    return;
+    return FALSE;
   }
 
   if (!(differencematte->shader[3] =
@@ -149,7 +154,7 @@ gst_gl_differencematte_init_gl_resources (GstGLFilter * filter)
                   texture_interp_fragment_source), NULL))) {
     GST_ELEMENT_ERROR (differencematte, RESOURCE, NOT_FOUND, ("%s",
             "Failed to compile interpolation shader"), ("%s", error->message));
-    return;
+    return FALSE;
   }
 
   /* FIXME: this should really be per shader */
@@ -159,13 +164,15 @@ gst_gl_differencematte_init_gl_resources (GstGLFilter * filter)
   filter->draw_attr_texture_loc =
       gst_gl_shader_get_attribute_location (differencematte->shader[2],
       "a_texcoord");
+
+  return TRUE;
 }
 
 /* free resources that need a gl context */
 static void
-gst_gl_differencematte_reset_gl_resources (GstGLFilter * filter)
+gst_gl_differencematte_gl_stop (GstGLBaseFilter * base_filter)
 {
-  GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (filter);
+  GstGLDifferenceMatte *differencematte = GST_GL_DIFFERENCEMATTE (base_filter);
   gint i;
 
   if (differencematte->savedbgtexture) {
@@ -197,6 +204,8 @@ gst_gl_differencematte_reset_gl_resources (GstGLFilter * filter)
   differencematte->location = NULL;
   differencematte->pixbuf = NULL;
   differencematte->bg_has_changed = FALSE;
+
+  GST_GL_BASE_FILTER_CLASS (parent_class)->gl_stop (base_filter);
 }
 
 static void
@@ -210,12 +219,11 @@ gst_gl_differencematte_class_init (GstGLDifferenceMatteClass * klass)
   gobject_class->set_property = gst_gl_differencematte_set_property;
   gobject_class->get_property = gst_gl_differencematte_get_property;
 
+  GST_GL_BASE_FILTER_CLASS (klass)->gl_start = gst_gl_differencematte_gl_start;
+  GST_GL_BASE_FILTER_CLASS (klass)->gl_stop = gst_gl_differencematte_gl_stop;
+
   GST_GL_FILTER_CLASS (klass)->filter_texture =
       gst_gl_differencematte_filter_texture;
-  GST_GL_FILTER_CLASS (klass)->display_init_cb =
-      gst_gl_differencematte_init_gl_resources;
-  GST_GL_FILTER_CLASS (klass)->display_reset_cb =
-      gst_gl_differencematte_reset_gl_resources;
 
   g_object_class_install_property (gobject_class,
       PROP_LOCATION,

ext/gl/gstgleffects.c

@@ -269,15 +269,19 @@ gst_gl_effects_set_effect (GstGLEffects * effects, gint effect_type)
 }
 
 /* init resources that need a gl context */
-static void
+static gboolean
-gst_gl_effects_init_gl_resources (GstGLFilter * filter)
+gst_gl_effects_gl_start (GstGLBaseFilter * base_filter)
 {
-  GstGLEffects *effects = GST_GL_EFFECTS (filter);
+  GstGLEffects *effects = GST_GL_EFFECTS (base_filter);
-  GstGLContext *context = GST_GL_BASE_FILTER (filter)->context;
+  GstGLFilter *filter = GST_GL_FILTER (base_filter);
+  GstGLContext *context = base_filter->context;
   GstGLBaseMemoryAllocator *base_alloc;
   GstGLAllocationParams *params;
   gint i;
 
+  if (!GST_GL_BASE_FILTER_CLASS (parent_class)->gl_start (base_filter))
+    return FALSE;
+
   base_alloc = (GstGLBaseMemoryAllocator *)
       gst_gl_memory_allocator_get_default (context);
   params =
@@ -295,23 +299,28 @@ gst_gl_effects_init_gl_resources (GstGLFilter * filter)
 
   gst_object_unref (base_alloc);
   gst_gl_allocation_params_free (params);
+
+  return TRUE;
 }
 
 /* free resources that need a gl context */
 static void
-gst_gl_effects_reset_gl_resources (GstGLFilter * filter)
+gst_gl_effects_gl_stop (GstGLBaseFilter * base_filter)
 {
-  GstGLEffects *effects = GST_GL_EFFECTS (filter);
+  GstGLEffects *effects = GST_GL_EFFECTS (base_filter);
-  GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
+  const GstGLFuncs *gl = base_filter->context->gl_vtable;
   gint i = 0;
 
   for (i = 0; i < NEEDED_TEXTURES; i++) {
     gst_memory_unref (GST_MEMORY_CAST (effects->midtexture[i]));
   }
+
   for (i = 0; i < GST_GL_EFFECTS_N_CURVES; i++) {
     gl->DeleteTextures (1, &effects->curve[i]);
     effects->curve[i] = 0;
   }
+
+  GST_GL_BASE_FILTER_CLASS (parent_class)->gl_stop (base_filter);
 }
 
 static void
@@ -322,11 +331,10 @@ gst_gl_effects_class_init (GstGLEffectsClass * klass)
   GST_BASE_TRANSFORM_CLASS (klass)->start = gst_gl_effects_init_resources;
   GST_BASE_TRANSFORM_CLASS (klass)->stop = gst_gl_effects_reset_resources;
 
+  GST_GL_BASE_FILTER_CLASS (klass)->gl_start = gst_gl_effects_gl_start;
+  GST_GL_BASE_FILTER_CLASS (klass)->gl_stop = gst_gl_effects_gl_stop;
+
   GST_GL_FILTER_CLASS (klass)->filter_texture = gst_gl_effects_filter_texture;
-  GST_GL_FILTER_CLASS (klass)->display_init_cb =
-      gst_gl_effects_init_gl_resources;
-  GST_GL_FILTER_CLASS (klass)->display_reset_cb =
-      gst_gl_effects_reset_gl_resources;
   GST_GL_FILTER_CLASS (klass)->init_fbo = gst_gl_effects_on_init_gl_context;
 
   klass->filter_descriptor = NULL;

ext/gl/gstglfiltercube.c

@@ -73,12 +73,10 @@ static void gst_gl_filter_cube_set_property (GObject * object, guint prop_id,
 static void gst_gl_filter_cube_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec);
 
-static gboolean gst_gl_filter_cube_stop (GstBaseTransform * trans);
-
 static gboolean gst_gl_filter_cube_set_caps (GstGLFilter * filter,
     GstCaps * incaps, GstCaps * outcaps);
-static void gst_gl_filter_cube_reset_gl (GstGLFilter * filter);
+static gboolean gst_gl_filter_cube_gl_start (GstGLBaseFilter * filter);
-static gboolean gst_gl_filter_cube_init_shader (GstGLFilter * filter);
+static void gst_gl_filter_cube_gl_stop (GstGLBaseFilter * filter);
 static gboolean _callback (gpointer stuff);
 static gboolean gst_gl_filter_cube_filter_texture (GstGLFilter * filter,
     GstGLMemory * in_tex, GstGLMemory * out_tex);
@@ -139,10 +137,9 @@ gst_gl_filter_cube_class_init (GstGLFilterCubeClass * klass)
   gobject_class->set_property = gst_gl_filter_cube_set_property;
   gobject_class->get_property = gst_gl_filter_cube_get_property;
 
-  GST_BASE_TRANSFORM_CLASS (klass)->stop = gst_gl_filter_cube_stop;
+  GST_GL_BASE_FILTER_CLASS (klass)->gl_start = gst_gl_filter_cube_gl_start;
+  GST_GL_BASE_FILTER_CLASS (klass)->gl_stop = gst_gl_filter_cube_gl_stop;
 
-  GST_GL_FILTER_CLASS (klass)->init_fbo = gst_gl_filter_cube_init_shader;
-  GST_GL_FILTER_CLASS (klass)->display_reset_cb = gst_gl_filter_cube_reset_gl;
   GST_GL_FILTER_CLASS (klass)->set_caps = gst_gl_filter_cube_set_caps;
   GST_GL_FILTER_CLASS (klass)->filter_texture =
       gst_gl_filter_cube_filter_texture;
@@ -278,10 +275,10 @@ gst_gl_filter_cube_set_caps (GstGLFilter * filter, GstCaps * incaps,
 }
 
 static void
-gst_gl_filter_cube_reset_gl (GstGLFilter * filter)
+gst_gl_filter_cube_gl_stop (GstGLBaseFilter * base_filter)
 {
-  GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (filter);
+  GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (base_filter);
-  const GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
+  const GstGLFuncs *gl = base_filter->context->gl_vtable;
 
   if (cube_filter->vao) {
     gl->DeleteVertexArrays (1, &cube_filter->vao);
@@ -298,37 +295,19 @@ gst_gl_filter_cube_reset_gl (GstGLFilter * filter)
     cube_filter->vbo_indices = 0;
   }
 
-  if (cube_filter->shader) {
-    gst_gl_context_del_shader (GST_GL_BASE_FILTER (filter)->context,
-        cube_filter->shader);
-    cube_filter->shader = NULL;
-  }
-}
-
-static gboolean
-gst_gl_filter_cube_stop (GstBaseTransform * trans)
-{
-  GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (trans);
-
-  /* blocking call, wait the opengl thread has destroyed the shader */
-  if (cube_filter->shader)
-    gst_gl_context_del_shader (GST_GL_BASE_FILTER (trans)->context,
-        cube_filter->shader);
-  cube_filter->shader = NULL;
-
-  return GST_BASE_TRANSFORM_CLASS (parent_class)->stop (trans);
-}
-
-static gboolean
-gst_gl_filter_cube_init_shader (GstGLFilter * filter)
-{
-  GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (filter);
-
   if (cube_filter->shader) {
     gst_object_unref (cube_filter->shader);
     cube_filter->shader = NULL;
   }
 
+  GST_GL_BASE_FILTER_CLASS (parent_class)->gl_stop (base_filter);
+}
+
+static gboolean
+gst_gl_filter_cube_gl_start (GstGLBaseFilter * filter)
+{
+  GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (filter);
+
   /* blocking call, wait the opengl thread has compiled the shader */
   return gst_gl_context_gen_shader (GST_GL_BASE_FILTER (filter)->context,
       cube_v_src, cube_f_src, &cube_filter->shader);

ext/gl/gstgloverlay.c

@@ -61,6 +61,7 @@ GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
 #define DEBUG_INIT \
   GST_DEBUG_CATEGORY_INIT (gst_gl_overlay_debug, "gloverlay", 0, "gloverlay element");
 
+#define gst_gl_overlay_parent_class parent_class
 G_DEFINE_TYPE_WITH_CODE (GstGLOverlay, gst_gl_overlay, GST_TYPE_GL_FILTER,
     DEBUG_INIT);
 
@@ -122,28 +123,26 @@ static const gchar *overlay_f_src =
 
 /* init resources that need a gl context */
 static gboolean
-gst_gl_overlay_init_gl_resources (GstGLFilter * filter)
+gst_gl_overlay_gl_start (GstGLBaseFilter * base_filter)
 {
-  GstGLOverlay *overlay = GST_GL_OVERLAY (filter);
+  GstGLOverlay *overlay = GST_GL_OVERLAY (base_filter);
 
-  if (overlay->shader)
+  if (!GST_GL_BASE_FILTER_CLASS (parent_class)->gl_start (base_filter))
-    gst_gl_context_del_shader (GST_GL_BASE_FILTER (filter)->context,
+    return FALSE;
-        overlay->shader);
 
-  return gst_gl_context_gen_shader (GST_GL_BASE_FILTER (filter)->context,
+  return gst_gl_context_gen_shader (base_filter->context, overlay_v_src,
-      overlay_v_src, overlay_f_src, &overlay->shader);
+      overlay_f_src, &overlay->shader);
 }
 
 /* free resources that need a gl context */
 static void
-gst_gl_overlay_reset_gl_resources (GstGLFilter * filter)
+gst_gl_overlay_gl_stop (GstGLBaseFilter * base_filter)
 {
-  GstGLOverlay *overlay = GST_GL_OVERLAY (filter);
+  GstGLOverlay *overlay = GST_GL_OVERLAY (base_filter);
-  const GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
+  const GstGLFuncs *gl = base_filter->context->gl_vtable;
 
   if (overlay->shader) {
-    gst_gl_context_del_shader (GST_GL_BASE_FILTER (filter)->context,
+    gst_object_unref (overlay->shader);
-        overlay->shader);
     overlay->shader = NULL;
   }
 
@@ -176,6 +175,8 @@ gst_gl_overlay_reset_gl_resources (GstGLFilter * filter)
     gl->DeleteBuffers (1, &overlay->overlay_vbo);
     overlay->overlay_vbo = 0;
   }
+
+  GST_GL_BASE_FILTER_CLASS (parent_class)->gl_stop (base_filter);
 }
 
 static void
@@ -190,11 +191,11 @@ gst_gl_overlay_class_init (GstGLOverlayClass * klass)
   gobject_class->set_property = gst_gl_overlay_set_property;
   gobject_class->get_property = gst_gl_overlay_get_property;
 
+  GST_GL_BASE_FILTER_CLASS (klass)->gl_start = gst_gl_overlay_gl_start;
+  GST_GL_BASE_FILTER_CLASS (klass)->gl_stop = gst_gl_overlay_gl_stop;
+
   GST_GL_FILTER_CLASS (klass)->set_caps = gst_gl_overlay_set_caps;
   GST_GL_FILTER_CLASS (klass)->filter_texture = gst_gl_overlay_filter_texture;
-  GST_GL_FILTER_CLASS (klass)->display_reset_cb =
-      gst_gl_overlay_reset_gl_resources;
-  GST_GL_FILTER_CLASS (klass)->init_fbo = gst_gl_overlay_init_gl_resources;
 
   GST_BASE_TRANSFORM_CLASS (klass)->before_transform =
       GST_DEBUG_FUNCPTR (gst_gl_overlay_before_transform);

ext/gl/gstgltransformation.c

@@ -103,9 +103,8 @@ static gboolean gst_gl_transformation_filter_meta (GstBaseTransform * trans,
 static gboolean gst_gl_transformation_decide_allocation (GstBaseTransform *
     trans, GstQuery * query);
 
-static void gst_gl_transformation_reset_gl (GstGLFilter * filter);
+static void gst_gl_transformation_gl_stop (GstGLBaseFilter * filter);
-static gboolean gst_gl_transformation_stop (GstBaseTransform * trans);
+static gboolean gst_gl_transformation_gl_start (GstGLBaseFilter * base_filter);
-static gboolean gst_gl_transformation_init_shader (GstGLFilter * filter);
 static gboolean gst_gl_transformation_callback (gpointer stuff);
 static void gst_gl_transformation_build_mvp (GstGLTransformation *
     transformation);
@@ -137,14 +136,13 @@ gst_gl_transformation_class_init (GstGLTransformationClass * klass)
       gst_gl_transformation_decide_allocation;
   base_transform_class->filter_meta = gst_gl_transformation_filter_meta;
 
-  GST_GL_FILTER_CLASS (klass)->init_fbo = gst_gl_transformation_init_shader;
+  GST_GL_BASE_FILTER_CLASS (klass)->gl_start = gst_gl_transformation_gl_start;
-  GST_GL_FILTER_CLASS (klass)->display_reset_cb =
+  GST_GL_BASE_FILTER_CLASS (klass)->gl_stop = gst_gl_transformation_gl_stop;
-      gst_gl_transformation_reset_gl;
+
   GST_GL_FILTER_CLASS (klass)->set_caps = gst_gl_transformation_set_caps;
   GST_GL_FILTER_CLASS (klass)->filter = gst_gl_transformation_filter;
   GST_GL_FILTER_CLASS (klass)->filter_texture =
       gst_gl_transformation_filter_texture;
-  GST_BASE_TRANSFORM_CLASS (klass)->stop = gst_gl_transformation_stop;
   GST_BASE_TRANSFORM_CLASS (klass)->prepare_output_buffer =
       gst_gl_transformation_prepare_output_buffer;
 
@@ -724,10 +722,10 @@ gst_gl_transformation_decide_allocation (GstBaseTransform * trans,
 }
 
 static void
-gst_gl_transformation_reset_gl (GstGLFilter * filter)
+gst_gl_transformation_gl_stop (GstGLBaseFilter * base_filter)
 {
-  GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);
+  GstGLTransformation *transformation = GST_GL_TRANSFORMATION (base_filter);
-  const GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;
+  const GstGLFuncs *gl = base_filter->context->gl_vtable;
 
   if (transformation->vao) {
     gl->DeleteVertexArrays (1, &transformation->vao);
@@ -748,36 +746,21 @@ gst_gl_transformation_reset_gl (GstGLFilter * filter)
     gst_object_unref (transformation->shader);
     transformation->shader = NULL;
   }
+
+  GST_GL_BASE_FILTER_CLASS (parent_class)->gl_stop (base_filter);
 }
 
 static gboolean
-gst_gl_transformation_stop (GstBaseTransform * trans)
+gst_gl_transformation_gl_start (GstGLBaseFilter * base_filter)
 {
-  GstGLBaseFilter *basefilter = GST_GL_BASE_FILTER (trans);
+  GstGLTransformation *transformation = GST_GL_TRANSFORMATION (base_filter);
-  GstGLTransformation *transformation = GST_GL_TRANSFORMATION (trans);
 
-  /* blocking call, wait until the opengl thread has destroyed the shader */
+  if (!GST_GL_BASE_FILTER_CLASS (parent_class)->gl_start (base_filter))
-  if (basefilter->context && transformation->shader) {
+    return FALSE;
-    gst_gl_context_del_shader (basefilter->context, transformation->shader);
-    transformation->shader = NULL;
-  }
 
-  return GST_BASE_TRANSFORM_CLASS (parent_class)->stop (trans);
+  if (gst_gl_context_get_gl_api (base_filter->context)) {
-}
-
-static gboolean
-gst_gl_transformation_init_shader (GstGLFilter * filter)
-{
-  GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);
-
-  if (transformation->shader) {
-    gst_object_unref (transformation->shader);
-    transformation->shader = NULL;
-  }
-
-  if (gst_gl_context_get_gl_api (GST_GL_BASE_FILTER (filter)->context)) {
     /* blocking call, wait until the opengl thread has compiled the shader */
-    return gst_gl_context_gen_shader (GST_GL_BASE_FILTER (filter)->context,
+    return gst_gl_context_gen_shader (base_filter->context,
         gst_gl_shader_string_vertex_mat4_vertex_transform,
         gst_gl_shader_string_fragment_default, &transformation->shader);
   }

gst-libs/gst/gl/gstglbasefilter.c

@@ -89,6 +89,9 @@ static gboolean gst_gl_base_filter_decide_allocation (GstBaseTransform * trans,
 static void gst_gl_base_filter_gl_start (GstGLContext * context, gpointer data);
 static void gst_gl_base_filter_gl_stop (GstGLContext * context, gpointer data);
 
+static gboolean gst_gl_base_filter_default_gl_start (GstGLBaseFilter * filter);
+static void gst_gl_base_filter_default_gl_stop (GstGLBaseFilter * filter);
+
 static void
 gst_gl_base_filter_class_init (GstGLBaseFilterClass * klass)
 {
@@ -121,6 +124,8 @@ gst_gl_base_filter_class_init (GstGLBaseFilterClass * klass)
           GST_TYPE_GL_CONTEXT, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
 
   klass->supported_gl_api = GST_GL_API_ANY;
+  klass->gl_start = gst_gl_base_filter_default_gl_start;
+  klass->gl_stop = gst_gl_base_filter_default_gl_stop;
 }
 
 static void
@@ -320,6 +325,12 @@ gst_gl_base_filter_stop (GstBaseTransform * bt)
   return TRUE;
 }
 
+static gboolean
+gst_gl_base_filter_default_gl_start (GstGLBaseFilter * filter)
+{
+  return TRUE;
+}
+
 static void
 gst_gl_base_filter_gl_start (GstGLContext * context, gpointer data)
 {
@@ -329,13 +340,12 @@ gst_gl_base_filter_gl_start (GstGLContext * context, gpointer data)
   gst_gl_insert_debug_marker (filter->context,
       "starting element %s", GST_OBJECT_NAME (filter));
 
-  if (filter_class->gl_start) {
   filter->priv->gl_result = filter_class->gl_start (filter);
-  } else {
+}
-    filter->priv->gl_result = TRUE;
-  }
 
-  filter->priv->gl_started |= filter->priv->gl_result;
+static void
+gst_gl_base_filter_default_gl_stop (GstGLBaseFilter * filter)
+{
 }
 
 static void
@@ -347,10 +357,8 @@ gst_gl_base_filter_gl_stop (GstGLContext * context, gpointer data)
   gst_gl_insert_debug_marker (filter->context,
       "stopping element %s", GST_OBJECT_NAME (filter));
 
-  if (filter->priv->gl_started) {
+  if (filter->priv->gl_started)
-    if (filter_class->gl_stop)
     filter_class->gl_stop (filter);
-  }
 
   filter->priv->gl_started = FALSE;
 }

gst-libs/gst/gl/gstglfilter.c

@@ -113,7 +113,6 @@ static gboolean gst_gl_filter_decide_allocation (GstBaseTransform * trans,
     GstQuery * query);
 static gboolean gst_gl_filter_set_caps (GstBaseTransform * bt, GstCaps * incaps,
     GstCaps * outcaps);
-static gboolean gst_gl_filter_gl_start (GstGLBaseFilter * filter);
 static void gst_gl_filter_gl_stop (GstGLBaseFilter * filter);
 static gboolean gst_gl_filter_gl_set_caps (GstGLBaseFilter * bt,
     GstCaps * incaps, GstCaps * outcaps);
@@ -142,7 +141,6 @@ gst_gl_filter_class_init (GstGLFilterClass * klass)
       gst_gl_filter_decide_allocation;
   GST_BASE_TRANSFORM_CLASS (klass)->get_unit_size = gst_gl_filter_get_unit_size;
 
-  GST_GL_BASE_FILTER_CLASS (klass)->gl_start = gst_gl_filter_gl_start;
   GST_GL_BASE_FILTER_CLASS (klass)->gl_stop = gst_gl_filter_gl_stop;
   GST_GL_BASE_FILTER_CLASS (klass)->gl_set_caps = gst_gl_filter_gl_set_caps;
 
@@ -199,29 +197,13 @@ gst_gl_filter_stop (GstBaseTransform * bt)
   return GST_BASE_TRANSFORM_CLASS (parent_class)->stop (bt);
 }
 
-static gboolean
-gst_gl_filter_gl_start (GstGLBaseFilter * base_filter)
-{
-  GstGLFilter *filter = GST_GL_FILTER (base_filter);
-  GstGLFilterClass *filter_class = GST_GL_FILTER_GET_CLASS (filter);
-
-  if (filter_class->display_init_cb)
-    filter_class->display_init_cb (filter);
-
-  return TRUE;
-}
-
 static void
 gst_gl_filter_gl_stop (GstGLBaseFilter * base_filter)
 {
   GstGLFilter *filter = GST_GL_FILTER (base_filter);
-  GstGLFilterClass *filter_class = GST_GL_FILTER_GET_CLASS (filter);
+  GstGLContext *context = base_filter->context;
-  GstGLContext *context = GST_GL_BASE_FILTER (filter)->context;
   const GstGLFuncs *gl = context->gl_vtable;
 
-  if (filter_class->display_reset_cb)
-    filter_class->display_reset_cb (filter);
-
   if (filter->vao) {
     gl->DeleteVertexArrays (1, &filter->vao);
     filter->vao = 0;
@@ -245,6 +227,8 @@ gst_gl_filter_gl_stop (GstGLBaseFilter * base_filter)
   filter->default_shader = NULL;
   filter->draw_attr_position_loc = -1;
   filter->draw_attr_texture_loc = -1;
+
+  GST_GL_BASE_FILTER_CLASS (parent_class)->gl_stop (base_filter);
 }
 
 static GstCaps *

gst-libs/gst/gl/gstglfilter.h

@@ -99,8 +99,6 @@ struct _GstGLFilter
  * @filter_texture: given @in_tex, transform it into @out_tex.  Not used
  *                  if @filter exists
  * @init_fbo: perform initialization when the Framebuffer object is created
- * @display_init_cb: execute arbitrary gl code on start
- * @display_reset_cb: execute arbitrary gl code at stop
  * @transform_internal_caps: Perform sub-class specific modifications of the
  *   caps to be processed between upload on input and before download for output.
  */
@@ -116,10 +114,6 @@ struct _GstGLFilterClass
   GstCaps *(*transform_internal_caps) (GstGLFilter *filter,
     GstPadDirection direction, GstCaps * caps, GstCaps * filter_caps);
 
-  /* useful to init and cleanup custom gl resources */
-  void (*display_init_cb)       (GstGLFilter *filter);
-  void (*display_reset_cb)      (GstGLFilter *filter);
-
   /* <private> */
   gpointer                      _padding[GST_PADDING];
 };