[videosink] Introduce ClutterGstRenderer

This structure is meant to abstract the work we have to do to actually
paint a frame. This way we can provide several backends to render the
same frame format (eg. between GLSL shaders or ARB fp1.0 fragment
programs) or build the caps of the GStreamer sink at run time after
having probed the GL implementation.

I420 and YV12 have been converted to work with this new abstraction.

1 files changed, 244 insertions, 156 deletions

diff --git a/clutter-gst/clutter-gst-video-sink.c b/clutter-gst/clutter-gst-video-sink.c
index 8607546..d682a3d 100644
--- a/clutter-gst/clutter-gst-video-sink.c
+++ b/clutter-gst/clutter-gst-video-sink.c
@@ -166,6 +166,34 @@ typedef enum
 typedef void (*GLUNIFORM1IPROC)(COGLint location, COGLint value);
 typedef void (*GLACTIVETEXTUREPROC)(GLenum unit);
 
+/*
+ * features: what does the underlaying video card supports ?
+ */
+typedef enum _ClutterGstFeatures
+{
+  CLUTTER_GST_FP             = 0x1, /* fragment programs (ARB fp1.0) */
+  CLUTTER_GST_GLSL           = 0x2, /* GLSL */
+  CLUTTER_GST_MULTI_TEXTURE  = 0x4, /* multi-texturing */
+} ClutterGstFeatures;
+
+/*
+ * renderer: abstracts a backend to render a frame.
+ */
+typedef struct _ClutterGstRenderer
+{
+ ClutterGstVideoFormat format;  /* the format handled by this renderer */
+ int flags;                     /* ClutterGstFeatures ORed flags */
+
+ void (*init)       (ClutterActor        *actor,
+                     ClutterGstVideoSink *sink);
+ void (*upload)     (ClutterGstVideoSink *sink,
+                     GstBuffer           *buffer);
+ void (*paint)      (ClutterActor        *actor,
+                     ClutterGstVideoSink *sink);
+ void (*post_paint) (ClutterActor        *actor,
+                     ClutterGstVideoSink *sink);
+} ClutterGstRenderer;
+
 struct _ClutterGstVideoSinkPrivate
 {
   ClutterTexture        *texture;
@@ -178,7 +206,6 @@ struct _ClutterGstVideoSinkPrivate
   GstBuffer             *buffer;
   guint                  idle_id;
 
-
   ClutterGstVideoFormat  format;
   gboolean               bgr;
   int                    width;
@@ -190,6 +217,8 @@ struct _ClutterGstVideoSinkPrivate
   
   GLUNIFORM1IPROC        glUniform1iARB;
   GLACTIVETEXTUREPROC    glActiveTexture;
+
+  ClutterGstRenderer    *renderer;
 };
 
 
@@ -206,41 +235,6 @@ GST_BOILERPLATE_FULL (ClutterGstVideoSink,
                       _do_init);
 
 static void
-clutter_gst_video_sink_base_init (gpointer g_class)
-{
-  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
-
-  gst_element_class_add_pad_template 
-                     (element_class,
-                      gst_static_pad_template_get (&sinktemplate_all));
-
-  gst_element_class_set_details (element_class, 
-                                 &clutter_gst_video_sink_details);
-}
-
-static void
-clutter_gst_video_sink_init (ClutterGstVideoSink      *sink,
-                             ClutterGstVideoSinkClass *klass)
-{
-  ClutterGstVideoSinkPrivate *priv;
-
-  sink->priv = priv =
-    G_TYPE_INSTANCE_GET_PRIVATE (sink, CLUTTER_GST_TYPE_VIDEO_SINK,
-                                 ClutterGstVideoSinkPrivate);
-
-  priv->buffer_lock = g_mutex_new ();
-  priv->use_shaders = TRUE;
-
-#ifdef CLUTTER_COGL_HAS_GL
-  priv->glUniform1iARB = (GLUNIFORM1IPROC)
-    cogl_get_proc_address ("glUniform1iARB");
-
-  priv->glActiveTexture = (GLACTIVETEXTUREPROC)
-    cogl_get_proc_address ("glActiveTexture");
-#endif
-}
-
-static void
 clutter_gst_video_sink_paint (ClutterActor        *actor,
                               ClutterGstVideoSink *sink)
 {
@@ -250,51 +244,6 @@ clutter_gst_video_sink_paint (ClutterActor        *actor,
 }
 
 static void
-clutter_gst_yv12_paint (ClutterActor        *actor,
-                        ClutterGstVideoSink *sink)
-{
-#ifdef CLUTTER_COGL_HAS_GL
-  ClutterGstVideoSinkPrivate *priv = sink->priv;
-  GLuint texture;
-  
-  /* Bind the U and V textures in texture units 1 and 2 */
-  if (priv->u_tex)
-    {
-      cogl_texture_get_gl_texture (priv->u_tex, &texture, NULL);
-      priv->glActiveTexture (GL_TEXTURE1);
-      glEnable (GL_TEXTURE_2D);
-      glBindTexture (GL_TEXTURE_2D, texture);
-    }
-
-  if (priv->v_tex)
-    {
-      cogl_texture_get_gl_texture (priv->v_tex, &texture, NULL);
-      priv->glActiveTexture (GL_TEXTURE2);
-      glEnable (GL_TEXTURE_2D);
-      glBindTexture (GL_TEXTURE_2D, texture);
-    }
-  
-  priv->glActiveTexture (GL_TEXTURE0_ARB);
-#endif
-}
-
-static void
-clutter_gst_yv12_post_paint (ClutterActor        *actor,
-                             ClutterGstVideoSink *sink)
-{
-#ifdef CLUTTER_COGL_HAS_GL
-  ClutterGstVideoSinkPrivate *priv = sink->priv;
-
-  /* Disable the extra texture units */
-  priv->glActiveTexture (GL_TEXTURE1);
-  glDisable (GL_TEXTURE_2D);
-  priv->glActiveTexture (GL_TEXTURE2);
-  glDisable (GL_TEXTURE_2D);
-  priv->glActiveTexture (GL_TEXTURE0);
-#endif
-}
-
-static void
 clutter_gst_video_sink_set_shader (ClutterGstVideoSink *sink,
                                    const gchar         *shader_src)
 {
@@ -349,6 +298,175 @@ clutter_gst_video_sink_set_shader (ClutterGstVideoSink *sink,
     }
 }
 
+#ifdef CLUTTER_COGL_HAS_GL
+
+/*
+ * YV12
+ *
+ * 8 bit Y plane followed by 8 bit 2x2 subsampled V and U planes.
+ */
+
+static void
+clutter_gst_yv12_glsl_init (ClutterActor        *actor,
+                            ClutterGstVideoSink *sink)
+{
+  ClutterGstVideoSinkPrivate *priv= sink->priv;
+  COGLint location;
+
+  clutter_gst_video_sink_set_shader (sink,
+                                     yv12_to_rgba_shader);
+
+  cogl_program_use (priv->program);
+  location = cogl_program_get_uniform_location (priv->program, "ytex");
+  priv->glUniform1iARB (location, 0);
+  location = cogl_program_get_uniform_location (priv->program, "utex");
+  priv->glUniform1iARB (location, 1);
+  location = cogl_program_get_uniform_location (priv->program, "vtex");
+  priv->glUniform1iARB (location, 2);
+
+  cogl_program_use (COGL_INVALID_HANDLE);
+}
+
+static void
+clutter_gst_yv12_glsl_upload (ClutterGstVideoSink *sink,
+                              GstBuffer           *buffer)
+{
+  ClutterGstVideoSinkPrivate *priv = sink->priv;
+
+  CoglHandle y_tex = cogl_texture_new_from_data (priv->width,
+                                                 priv->height,
+                                                 -1,
+                                                 FALSE,
+                                                 COGL_PIXEL_FORMAT_G_8,
+                                                 COGL_PIXEL_FORMAT_G_8,
+                                                 priv->width,
+                                                 GST_BUFFER_DATA (buffer));
+  cogl_texture_set_filters (y_tex, CGL_LINEAR, CGL_LINEAR);
+  clutter_texture_set_cogl_texture (priv->texture, y_tex);
+  cogl_texture_unref (y_tex);
+
+  if (priv->u_tex)
+    cogl_texture_unref (priv->u_tex);
+
+  if (priv->v_tex)
+    cogl_texture_unref (priv->v_tex);
+
+  priv->v_tex = cogl_texture_new_from_data (priv->width/2,
+                                            priv->height/2,
+                                            -1,
+                                            FALSE,
+                                            COGL_PIXEL_FORMAT_G_8,
+                                            COGL_PIXEL_FORMAT_G_8,
+                                            priv->width/2,
+                                            GST_BUFFER_DATA (buffer) +
+                                            (priv->width * priv->height));
+  cogl_texture_set_filters (priv->v_tex, CGL_LINEAR, CGL_LINEAR);
+
+  priv->u_tex =
+    cogl_texture_new_from_data (priv->width/2,
+                                priv->height/2,
+                                -1,
+                                FALSE,
+                                COGL_PIXEL_FORMAT_G_8,
+                                COGL_PIXEL_FORMAT_G_8,
+                                priv->width/2,
+                                GST_BUFFER_DATA (buffer) +
+                                (priv->width * priv->height) +
+                                (priv->width/2 * priv->height/2));
+  cogl_texture_set_filters (priv->u_tex, CGL_LINEAR, CGL_LINEAR);
+}
+
+static void
+clutter_gst_yv12_glsl_paint (ClutterActor        *actor,
+                             ClutterGstVideoSink *sink)
+{
+  ClutterGstVideoSinkPrivate *priv = sink->priv;
+  GLuint texture;
+
+  /* Bind the U and V textures in texture units 1 and 2 */
+  if (priv->u_tex)
+    {
+      cogl_texture_get_gl_texture (priv->u_tex, &texture, NULL);
+      priv->glActiveTexture (GL_TEXTURE1);
+      glEnable (GL_TEXTURE_2D);
+      glBindTexture (GL_TEXTURE_2D, texture);
+    }
+
+  if (priv->v_tex)
+    {
+      cogl_texture_get_gl_texture (priv->v_tex, &texture, NULL);
+      priv->glActiveTexture (GL_TEXTURE2);
+      glEnable (GL_TEXTURE_2D);
+      glBindTexture (GL_TEXTURE_2D, texture);
+    }
+
+  priv->glActiveTexture (GL_TEXTURE0_ARB);
+}
+
+
+static void
+clutter_gst_yv12_glsl_post_paint (ClutterActor        *actor,
+                                  ClutterGstVideoSink *sink)
+{
+  ClutterGstVideoSinkPrivate *priv = sink->priv;
+
+  /* Disable the extra texture units */
+  priv->glActiveTexture (GL_TEXTURE1);
+  glDisable (GL_TEXTURE_2D);
+  priv->glActiveTexture (GL_TEXTURE2);
+  glDisable (GL_TEXTURE_2D);
+  priv->glActiveTexture (GL_TEXTURE0);
+}
+
+static ClutterGstRenderer yv12_glsl_renderer =
+{
+  CLUTTER_GST_YV12,
+  CLUTTER_GST_GLSL | CLUTTER_GST_MULTI_TEXTURE,
+  clutter_gst_yv12_glsl_init,
+  clutter_gst_yv12_glsl_upload,
+  clutter_gst_yv12_glsl_paint,
+  clutter_gst_yv12_glsl_post_paint,
+};
+
+/*
+ * I420
+ *
+ * 8 bit Y plane followed by 8 bit 2x2 subsampled U and V planes.
+ * Basically the same as YV12, but with the 2 chroma planes switched.
+ */
+
+static void
+clutter_gst_i420_glsl_init (ClutterActor        *actor,
+                            ClutterGstVideoSink *sink)
+{
+  ClutterGstVideoSinkPrivate *priv = sink->priv;
+  COGLint location;
+
+  clutter_gst_video_sink_set_shader (sink,
+                                     yv12_to_rgba_shader);
+
+  cogl_program_use (priv->program);
+  location = cogl_program_get_uniform_location (priv->program, "ytex");
+  priv->glUniform1iARB (location, 0);
+  location = cogl_program_get_uniform_location (priv->program, "vtex");
+  priv->glUniform1iARB (location, 1);
+  location = cogl_program_get_uniform_location (priv->program, "utex");
+  priv->glUniform1iARB (location, 2);
+  cogl_program_use (COGL_INVALID_HANDLE);
+}
+
+static ClutterGstRenderer i420_glsl_renderer =
+{
+  CLUTTER_GST_I420,
+  CLUTTER_GST_GLSL | CLUTTER_GST_MULTI_TEXTURE,
+  clutter_gst_i420_glsl_init,
+  clutter_gst_yv12_glsl_upload,
+  clutter_gst_yv12_glsl_paint,
+  clutter_gst_yv12_glsl_post_paint,
+};
+
+#endif /* CLUTTER_COGL_HAS_GL */
+
 static gboolean
 clutter_gst_video_sink_idle_func (gpointer data)
 {
@@ -414,90 +532,21 @@ clutter_gst_video_sink_idle_func (gpointer data)
     }
   else if (priv->format == CLUTTER_GST_YV12 || priv->format == CLUTTER_GST_I420)
     {
-      CoglHandle y_tex =
-        cogl_texture_new_from_data (priv->width,
-                                    priv->height,
-                                    -1,
-                                    FALSE,
-                                    COGL_PIXEL_FORMAT_G_8,
-                                    COGL_PIXEL_FORMAT_G_8,
-                                    priv->width,
-                                    GST_BUFFER_DATA (buffer));
-      cogl_texture_set_filters (y_tex, CGL_LINEAR, CGL_LINEAR);
-      clutter_texture_set_cogl_texture (priv->texture, y_tex);
-      cogl_texture_unref (y_tex);
-      
-      if (priv->u_tex)
-        cogl_texture_unref (priv->u_tex);
-      
-      if (priv->v_tex)
-        cogl_texture_unref (priv->v_tex);
       
-      priv->v_tex =
-        cogl_texture_new_from_data (priv->width/2,
-                                    priv->height/2,
-                                    -1,
-                                    FALSE,
-                                    COGL_PIXEL_FORMAT_G_8,
-                                    COGL_PIXEL_FORMAT_G_8,
-                                    priv->width/2,
-                                    GST_BUFFER_DATA (buffer) +
-                                      (priv->width * priv->height));
-      cogl_texture_set_filters (priv->v_tex, CGL_LINEAR, CGL_LINEAR);
-
-      priv->u_tex =
-        cogl_texture_new_from_data (priv->width/2,
-                                    priv->height/2,
-                                    -1,
-                                    FALSE,
-                                    COGL_PIXEL_FORMAT_G_8,
-                                    COGL_PIXEL_FORMAT_G_8,
-                                    priv->width/2,
-                                    GST_BUFFER_DATA (buffer) +
-                                      (priv->width * priv->height) +
-                                      (priv->width/2 * priv->height/2));
-      cogl_texture_set_filters (priv->u_tex, CGL_LINEAR, CGL_LINEAR);
-      
-      /* Initialise YV12 shader */
+      priv->renderer->upload (sink, buffer);
+
+      /* Initialize renderer */
       if (!priv->shaders_init)
         {
-#ifdef CLUTTER_COGL_HAS_GL
-          COGLint location;
-          clutter_gst_video_sink_set_shader (sink,
-                                             yv12_to_rgba_shader);
-          
-          cogl_program_use (priv->program);
-          location = cogl_program_get_uniform_location (priv->program, "ytex");
-          priv->glUniform1iARB (location, 0);
-          if (priv->format == CLUTTER_GST_YV12)
-            {
-              location = cogl_program_get_uniform_location (priv->program,
-                                                            "utex");
-              priv->glUniform1iARB (location, 1);
-              location = cogl_program_get_uniform_location (priv->program,
-                                                            "vtex");
-              priv->glUniform1iARB (location, 2);
-            }
-          else /* I420 */
-            {
-              location = cogl_program_get_uniform_location (priv->program,
-                                                            "vtex");
-              priv->glUniform1iARB (location, 1);
-              location = cogl_program_get_uniform_location (priv->program,
-                                                            "utex");
-              priv->glUniform1iARB (location, 2);
-            }
-          cogl_program_use (COGL_INVALID_HANDLE);
-          
+          priv->renderer->init (CLUTTER_ACTOR (priv->texture), sink);
           g_signal_connect (priv->texture,
                             "paint",
-                            G_CALLBACK (clutter_gst_yv12_paint),
+                            G_CALLBACK (priv->renderer->paint),
                             sink);
           g_signal_connect_after (priv->texture,
                                   "paint",
-                                  G_CALLBACK (clutter_gst_yv12_post_paint),
+                                  G_CALLBACK (priv->renderer->post_paint),
                                   sink);
-#endif
         }
     }
 
@@ -506,6 +555,41 @@ clutter_gst_video_sink_idle_func (gpointer data)
   return FALSE;
 }
 
+static void
+clutter_gst_video_sink_base_init (gpointer g_class)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+  gst_element_class_add_pad_template
+                     (element_class,
+                      gst_static_pad_template_get (&sinktemplate_all));
+
+  gst_element_class_set_details (element_class,
+                                 &clutter_gst_video_sink_details);
+}
+
+static void
+clutter_gst_video_sink_init (ClutterGstVideoSink      *sink,
+                             ClutterGstVideoSinkClass *klass)
+{
+  ClutterGstVideoSinkPrivate *priv;
+
+  sink->priv = priv =
+    G_TYPE_INSTANCE_GET_PRIVATE (sink, CLUTTER_GST_TYPE_VIDEO_SINK,
+                                 ClutterGstVideoSinkPrivate);
+
+  priv->buffer_lock = g_mutex_new ();
+  priv->use_shaders = TRUE;
+
+#ifdef CLUTTER_COGL_HAS_GL
+  priv->glUniform1iARB = (GLUNIFORM1IPROC)
+    cogl_get_proc_address ("glUniform1iARB");
+
+  priv->glActiveTexture = (GLACTIVETEXTUREPROC)
+    cogl_get_proc_address ("glActiveTexture");
+#endif
+}
+
 static GstFlowReturn
 clutter_gst_video_sink_render (GstBaseSink *bsink,
                                GstBuffer   *buffer)
@@ -613,14 +697,17 @@ clutter_gst_video_sink_set_caps (GstBaseSink *bsink,
   else 
     priv->par_n = priv->par_d = 1;
 
+#if CLUTTER_COGL_HAS_GL
   ret = gst_structure_get_fourcc (structure, "format", &fourcc);
   if (ret && (fourcc == GST_RIFF_YV12))
     {
       priv->format = CLUTTER_GST_YV12;
+      priv->renderer = &yv12_glsl_renderer;
     }
   else if (ret && (fourcc == GST_MAKE_FOURCC ('I', '4', '2', '0')))
     {
       priv->format = CLUTTER_GST_I420;
+      priv->renderer = &i420_glsl_renderer;
     }
   else if (ret && (fourcc == GST_MAKE_FOURCC ('A', 'Y', 'U', 'V')))
     {
@@ -628,6 +715,7 @@ clutter_gst_video_sink_set_caps (GstBaseSink *bsink,
       priv->bgr = FALSE;
     }
   else
+#endif
     {
       guint32 width;
       gst_structure_get_int (structure, "red_mask", &red_mask);