[127/906] Imported GstGLShader from cvs branch. Added a demo laplacian convolution filter to demonstrate how this can be integrated with minimum effort.

gst-libs/gst/gl/Makefile.am

@@ -4,13 +4,15 @@ lib_LTLIBRARIES = libgstgl-@GST_MAJORMINOR@.la
 libgstgl_@GST_MAJORMINOR@_la_SOURCES = \
 	gstgldisplay.c \
 	gstglbuffer.c \
-	gstglfilter.c
+	gstglfilter.c \
+	gstglshader.c
 
 libgstgl_@GST_MAJORMINOR@includedir = $(includedir)/gstreamer-@GST_MAJORMINOR@/gst/gl
 libgstgl_@GST_MAJORMINOR@include_HEADERS = \
 	gstgldisplay.h \
 	gstglbuffer.h \
-	gstglfilter.h
+	gstglfilter.h \
+	gstglshader.h
 
 libgstgl_@GST_MAJORMINOR@_la_LIBADD = \
 	$(GST_PLUGINS_BASE_LIBS) -lgstvideo-$(GST_MAJORMINOR) \

gst-libs/gst/gl/gstglshader.c

@@ -0,0 +1,497 @@
+/* 
+ * GStreamer
+ * Copyright (C) 2008 Filippo Argiolas <filippo.argiolas@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstglshader.h"
+
+#define GST_GL_SHADER_GET_PRIVATE(o)					\
+  (G_TYPE_INSTANCE_GET_PRIVATE((o), GST_GL_TYPE_SHADER, GstGLShaderPrivate))
+
+enum
+{
+  PROP_0,
+  PROP_VERTEX_SRC,
+  PROP_FRAGMENT_SRC,
+  PROP_COMPILED,
+  PROP_ACTIVE                   //unused
+};
+
+struct _GstGLShaderPrivate
+{
+  gchar *vertex_src;
+  gchar *fragment_src;
+
+  GLhandleARB vertex_handle;
+  GLhandleARB fragment_handle;
+  GLhandleARB program_handle;
+
+  gboolean compiled;
+  gboolean active;
+};
+
+G_DEFINE_TYPE (GstGLShader, gst_gl_shader, G_TYPE_OBJECT);
+
+static void
+gst_gl_shader_finalize (GObject * object)
+{
+  GstGLShader *shader;
+  GstGLShaderPrivate *priv;
+/*  GLint status = GL_FALSE; */
+
+  shader = GST_GL_SHADER (object);
+  priv = shader->priv;
+
+  g_free (priv->vertex_src);
+  g_free (priv->fragment_src);
+
+  /* release shader objects */
+  gst_gl_shader_release (shader);
+
+  /* delete program */
+  if (priv->program_handle) {
+    glDeleteObjectARB (priv->program_handle);
+    glGetError ();
+    /* g_debug ("error: 0x%x", err);  */
+    /* glGetObjectParameterivARB(priv->program_handle, GL_OBJECT_DELETE_STATUS_ARB, &status); */
+    /* g_debug ("program deletion status:%s", status == GL_TRUE ? "true" : "false" ); */
+  }
+
+  priv->fragment_handle = 0;
+  priv->vertex_handle = 0;
+  priv->program_handle = 0;
+
+  G_OBJECT_CLASS (gst_gl_shader_parent_class)->finalize (object);
+}
+
+static void
+gst_gl_shader_set_property (GObject * object,
+    guint prop_id, const GValue * value, GParamSpec * pspec)
+{
+  GstGLShader *shader = GST_GL_SHADER (object);
+
+  switch (prop_id) {
+    case PROP_VERTEX_SRC:
+      gst_gl_shader_set_vertex_source (shader, g_value_get_string (value));
+      break;
+    case PROP_FRAGMENT_SRC:
+      gst_gl_shader_set_fragment_source (shader, g_value_get_string (value));
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_gl_shader_get_property (GObject * object,
+    guint prop_id, GValue * value, GParamSpec * pspec)
+{
+  GstGLShader *shader = GST_GL_SHADER (object);
+  GstGLShaderPrivate *priv = shader->priv;
+
+  switch (prop_id) {
+    case PROP_VERTEX_SRC:
+      g_value_set_string (value, priv->vertex_src);
+      break;
+    case PROP_FRAGMENT_SRC:
+      g_value_set_string (value, priv->fragment_src);
+      break;
+    case PROP_COMPILED:
+      g_value_set_boolean (value, priv->compiled);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+
+}
+
+static void
+gst_gl_shader_class_init (GstGLShaderClass * klass)
+{
+  /* bind class methods .. */
+  GObjectClass *obj_class = G_OBJECT_CLASS (klass);
+
+  g_type_class_add_private (klass, sizeof (GstGLShaderPrivate));
+
+  obj_class->finalize = gst_gl_shader_finalize;
+  obj_class->set_property = gst_gl_shader_set_property;
+  obj_class->get_property = gst_gl_shader_get_property;
+
+  /* .. and install properties */
+
+  g_object_class_install_property (obj_class,
+      PROP_VERTEX_SRC,
+      g_param_spec_string ("vertex-src",
+          "Vertex Source",
+          "GLSL Vertex Shader source code", NULL, G_PARAM_READWRITE));
+  g_object_class_install_property (obj_class,
+      PROP_FRAGMENT_SRC,
+      g_param_spec_string ("fragment-src",
+          "Fragment Source",
+          "GLSL Fragment Shader source code", NULL, G_PARAM_READWRITE));
+  g_object_class_install_property (obj_class,
+      PROP_ACTIVE,
+      g_param_spec_string ("active",
+          "Active", "Enable/Disable the shader", NULL, G_PARAM_READWRITE));
+  g_object_class_install_property (obj_class,
+      PROP_COMPILED,
+      g_param_spec_boolean ("compiled",
+          "Compiled",
+          "Shader compile and link status", FALSE, G_PARAM_READABLE));
+}
+
+void
+gst_gl_shader_set_vertex_source (GstGLShader * shader, const gchar * src)
+{
+  GstGLShaderPrivate *priv;
+
+  g_return_if_fail (GST_GL_IS_SHADER (shader));
+  g_return_if_fail (src != NULL);
+
+  priv = shader->priv;
+
+  if (gst_gl_shader_is_compiled (shader))
+    gst_gl_shader_release (shader);
+
+  g_free (priv->vertex_src);
+
+  priv->vertex_src = g_strdup (src);
+}
+
+void
+gst_gl_shader_set_fragment_source (GstGLShader * shader, const gchar * src)
+{
+  GstGLShaderPrivate *priv;
+
+  g_return_if_fail (GST_GL_IS_SHADER (shader));
+  g_return_if_fail (src != NULL);
+
+  priv = shader->priv;
+
+  if (gst_gl_shader_is_compiled (shader))
+    gst_gl_shader_release (shader);
+
+  g_free (priv->fragment_src);
+
+  priv->fragment_src = g_strdup (src);
+}
+
+G_CONST_RETURN gchar *
+gst_gl_shader_get_vertex_source (GstGLShader * shader)
+{
+  g_return_val_if_fail (GST_GL_IS_SHADER (shader), NULL);
+  return shader->priv->vertex_src;
+}
+
+G_CONST_RETURN gchar *
+gst_gl_shader_get_fragment_source (GstGLShader * shader)
+{
+  g_return_val_if_fail (GST_GL_IS_SHADER (shader), NULL);
+  return shader->priv->fragment_src;
+}
+
+static void
+gst_gl_shader_init (GstGLShader * self)
+{
+  /* initialize sources and create program object */
+  GstGLShaderPrivate *priv;
+
+  priv = self->priv = GST_GL_SHADER_GET_PRIVATE (self);
+
+  priv->vertex_src = NULL;
+  priv->fragment_src = NULL;
+
+  priv->fragment_handle = 0;
+  priv->vertex_handle = 0;
+  priv->program_handle = glCreateProgramObjectARB ();
+
+  g_assert (priv->program_handle);
+
+  priv->compiled = FALSE;
+  priv->active = FALSE;         // unused at the moment
+}
+
+GstGLShader *
+gst_gl_shader_new (void)
+{
+  return g_object_new (GST_GL_TYPE_SHADER, NULL);
+}
+
+gboolean
+gst_gl_shader_is_compiled (GstGLShader * shader)
+{
+  g_return_val_if_fail (GST_GL_IS_SHADER (shader), FALSE);
+
+  return shader->priv->compiled;
+}
+
+gboolean
+gst_gl_shader_compile (GstGLShader * shader, GError ** error)
+{
+  GstGLShaderPrivate *priv;
+
+  gchar info_buffer[2048];
+  GLsizei len = 0;
+  GLint status = GL_FALSE;
+
+  g_return_val_if_fail (GST_GL_IS_SHADER (shader), FALSE);
+
+  priv = shader->priv;
+
+  if (priv->compiled)
+    return priv->compiled;
+
+  g_assert (priv->program_handle);
+
+  if (priv->vertex_src) {
+    /* create vertex object */
+    const gchar *vertex_source = priv->vertex_src;
+    priv->vertex_handle = glCreateShaderObjectARB (GL_VERTEX_SHADER);
+    glShaderSourceARB (priv->vertex_handle, 1, &vertex_source, NULL);
+    /* compile */
+    glCompileShaderARB (priv->vertex_handle);
+    /* check everything is ok */
+    glGetObjectParameterivARB (priv->vertex_handle,
+        GL_OBJECT_COMPILE_STATUS_ARB, &status);
+
+    glGetInfoLogARB (priv->vertex_handle,
+        sizeof (info_buffer) - 1, &len, info_buffer);
+    info_buffer[len] = '\0';
+
+    if (status != GL_TRUE) {
+      g_set_error (error, GST_GL_SHADER_ERROR,
+          GST_GL_SHADER_ERROR_COMPILE,
+          "Vertex Shader compilation failed:\n%s", info_buffer);
+
+      glDeleteObjectARB (priv->vertex_handle);
+      priv->compiled = FALSE;
+      return priv->compiled;
+    } else if (len > 1) {
+      g_debug ("\n%s\n", info_buffer);
+    }
+    glAttachObjectARB (priv->program_handle, priv->vertex_handle);
+  }
+
+  if (priv->fragment_src) {
+    /* create fragment object */
+    const gchar *fragment_source = priv->fragment_src;
+    priv->fragment_handle = glCreateShaderObjectARB (GL_FRAGMENT_SHADER_ARB);
+    glShaderSourceARB (priv->fragment_handle, 1, &fragment_source, NULL);
+    /* compile */
+    glCompileShaderARB (priv->fragment_handle);
+    /* check everything is ok */
+    glGetObjectParameterivARB (priv->fragment_handle,
+        GL_OBJECT_COMPILE_STATUS_ARB, &status);
+
+    glGetInfoLogARB (priv->fragment_handle,
+        sizeof (info_buffer) - 1, &len, info_buffer);
+    info_buffer[len] = '\0';
+    if (status != GL_TRUE) {
+      g_set_error (error, GST_GL_SHADER_ERROR,
+          GST_GL_SHADER_ERROR_COMPILE,
+          "Fragment Shader compilation failed:\n%s", info_buffer);
+
+      glDeleteObjectARB (priv->fragment_handle);
+      priv->compiled = FALSE;
+      return priv->compiled;
+    } else if (len > 1) {
+      g_debug ("\n%s\n", info_buffer);
+    }
+    glAttachObjectARB (priv->program_handle, priv->fragment_handle);
+  }
+
+  /* if nothing failed link shaders */
+  glLinkProgramARB (priv->program_handle);
+
+  glGetObjectParameterivARB (priv->program_handle, GL_LINK_STATUS, &status);
+
+  glGetInfoLogARB (priv->program_handle,
+      sizeof (info_buffer) - 1, &len, info_buffer);
+  info_buffer[len] = '\0';
+
+  if (status != GL_TRUE) {
+    g_set_error (error, GST_GL_SHADER_ERROR,
+        GST_GL_SHADER_ERROR_LINK, "Shader Linking failed:\n%s", info_buffer);
+    priv->compiled = FALSE;
+    return priv->compiled;
+  } else if (len > 1) {
+    g_debug ("\n%s\n", info_buffer);
+  }
+  /* success! */
+  priv->compiled = TRUE;
+  g_object_notify (G_OBJECT (shader), "compiled");
+
+  return priv->compiled;
+}
+
+void
+gst_gl_shader_release (GstGLShader * shader)
+{
+  GstGLShaderPrivate *priv;
+  /* GLint status; */
+  /* GLenum err = 0; */
+
+  g_return_if_fail (GST_GL_IS_SHADER (shader));
+
+  priv = shader->priv;
+
+  g_assert (priv->program_handle);
+
+  if (!priv->compiled)
+    return;
+
+  if (priv->vertex_handle) {    // not needed but nvidia doesn't care to respect the spec
+    glDeleteObjectARB (priv->vertex_handle);
+
+    /* err = glGetError (); */
+    /* g_debug ("error: 0x%x", err); */
+    /* glGetObjectParameterivARB(priv->vertex_handle, GL_OBJECT_DELETE_STATUS_ARB, &status); */
+    /* g_debug ("vertex deletion status:%s", status == GL_TRUE ? "true" : "false" ); */
+  }
+
+  if (priv->fragment_handle) {
+    glDeleteObjectARB (priv->fragment_handle);
+
+    /* err = glGetError (); */
+    /* g_debug ("error: 0x%x", err); */
+    /* glGetObjectParameterivARB(priv->fragment_handle, GL_OBJECT_DELETE_STATUS_ARB, &status); */
+    /* g_debug ("fragment deletion status:%s", status == GL_TRUE ? "true" : "false" ); */
+  }
+
+  if (priv->vertex_handle)
+    glDetachObjectARB (priv->program_handle, priv->vertex_handle);
+  if (priv->fragment_handle)
+    glDetachObjectARB (priv->program_handle, priv->fragment_handle);
+
+  priv->compiled = FALSE;
+  g_object_notify (G_OBJECT (shader), "compiled");
+}
+
+void
+gst_gl_shader_use (GstGLShader * shader)
+{
+  GstGLShaderPrivate *priv;
+
+  if (!shader) {
+    glUseProgramObjectARB (0);
+    return;
+  }
+
+  priv = shader->priv;
+
+  g_assert (priv->program_handle);
+
+  glUseProgramObjectARB (priv->program_handle);
+
+  return;
+}
+
+gboolean
+gst_gl_shader_compile_and_check (GstGLShader * shader,
+    const gchar * source, GstGLShaderSourceType type)
+{
+  gboolean is_compiled = FALSE;
+
+  g_object_get (G_OBJECT (shader), "compiled", &is_compiled, NULL);
+
+  if (!is_compiled) {
+    GError *error = NULL;
+
+    switch (type) {
+      case GST_GL_SHADER_FRAGMENT_SOURCE:
+        gst_gl_shader_set_fragment_source (shader, source);
+        break;
+      case GST_GL_SHADER_VERTEX_SOURCE:
+        gst_gl_shader_set_vertex_source (shader, source);
+        break;
+      default:
+        g_assert_not_reached ();
+        break;
+    }
+
+    gst_gl_shader_compile (shader, &error);
+    if (error) {
+      g_warning ("%s", error->message);
+      g_error_free (error);
+      error = NULL;
+      gst_gl_shader_use (NULL);
+      return FALSE;
+    }
+  }
+  return TRUE;
+}
+
+void
+gst_gl_shader_set_uniform_1f (GstGLShader * shader, const gchar * name,
+    gfloat value)
+{
+  GstGLShaderPrivate *priv;
+  GLint location = -1;
+
+  priv = shader->priv;
+
+  g_return_if_fail (priv->program_handle != 0);
+
+  location = glGetUniformLocationARB (priv->program_handle, name);
+
+  glUniform1fARB (location, value);
+}
+
+void
+gst_gl_shader_set_uniform_1fv (GstGLShader * shader, const gchar * name,
+    guint count, gfloat * value)
+{
+  GstGLShaderPrivate *priv;
+  GLint location = -1;
+
+  priv = shader->priv;
+
+  g_return_if_fail (priv->program_handle != 0);
+
+  location = glGetUniformLocationARB (priv->program_handle, name);
+
+  glUniform1fvARB (location, count, value);
+}
+
+void
+gst_gl_shader_set_uniform_1i (GstGLShader * shader, const gchar * name,
+    gint value)
+{
+  GstGLShaderPrivate *priv;
+  GLint location = -1;
+
+  priv = shader->priv;
+
+  g_return_if_fail (priv->program_handle != 0);
+
+  location = glGetUniformLocationARB (priv->program_handle, name);
+
+  glUniform1iARB (location, value);
+}
+
+GQuark
+gst_gl_shader_error_quark (void)
+{
+  return g_quark_from_static_string ("gst-gl-shader-error");
+}

gst-libs/gst/gl/gstglshader.h

@@ -0,0 +1,94 @@
+/* 
+ * GStreamer
+ * Copyright (C) 2008 Filippo Argiolas <filippo.argiolas@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef __GST_GL_SHADER_H__
+#define __GST_GL_SHADER_H__
+
+#include <GL/glew.h>
+#include <gst/gst.h>
+
+G_BEGIN_DECLS
+
+#define GST_GL_TYPE_SHADER         (gst_gl_shader_get_type())
+#define GST_GL_SHADER(o)           (G_TYPE_CHECK_INSTANCE_CAST((o), GST_GL_TYPE_SHADER, GstGLShader))
+#define GST_GL_SHADER_CLASS(k)     (G_TYPE_CHECK_CLASS((k), GST_GL_TYPE_SHADER, GstGLShaderClass))
+#define GST_GL_IS_SHADER(o)        (G_TYPE_CHECK_INSTANCE_TYPE((o), GST_GL_TYPE_SHADER))
+#define GST_GL_IS_SHADER_CLASS(k)  (G_TYPE_CHECK_CLASS_TYPE((k), GST_GL_TYPE_SHADER))
+#define GST_GL_SHADER_GET_CLASS(o) (G_TYPE_INSTANCE_GET_CLASS((o), GST_GL_TYPE_SHADER, GstGLShaderClass))
+
+#define GST_GL_SHADER_ERROR (gst_gl_shader_error_quark ())
+
+typedef enum {
+  GST_GL_SHADER_ERROR_COMPILE,
+  GST_GL_SHADER_ERROR_LINK,
+  GST_GL_SHADER_ERROR_PROGRAM
+} GstGLShaderError;
+
+typedef enum {
+  GST_GL_SHADER_FRAGMENT_SOURCE,
+  GST_GL_SHADER_VERTEX_SOURCE
+} GstGLShaderSourceType;
+
+typedef struct _GstGLShader        GstGLShader;
+typedef struct _GstGLShaderPrivate GstGLShaderPrivate;
+typedef struct _GstGLShaderClass   GstGLShaderClass;
+
+struct _GstGLShader {
+  /*< private >*/
+  GObject parent;
+  GstGLShaderPrivate *priv;
+};
+
+struct _GstGLShaderClass {
+  /*< private >*/
+  GObjectClass parent_class;
+};
+
+/* methods */
+
+GQuark gst_gl_shader_error_quark (void);
+GType gst_gl_shader_get_type (void);
+
+GstGLShader * gst_gl_shader_new (void);
+
+void gst_gl_shader_set_vertex_source   (GstGLShader *shader, 
+					const gchar *src);
+void gst_gl_shader_set_fragment_source (GstGLShader *shader, 
+					const gchar *src);
+G_CONST_RETURN gchar * gst_gl_shader_get_vertex_source (GstGLShader *shader);
+G_CONST_RETURN gchar * gst_gl_shader_get_fragment_source (GstGLShader *shader);
+
+void gst_gl_shader_set_active (GstGLShader *shader,
+			       gboolean active);
+
+gboolean gst_gl_shader_is_compiled (GstGLShader *shader);
+
+gboolean gst_gl_shader_compile (GstGLShader *shader, GError **error);
+gboolean gst_gl_shader_compile_and_check (GstGLShader *shader, const gchar *source, GstGLShaderSourceType type);
+void gst_gl_shader_release (GstGLShader *shader);
+void gst_gl_shader_use (GstGLShader *shader);
+
+void gst_gl_shader_set_uniform_1i (GstGLShader *shader, const gchar *name, gint value);
+void gst_gl_shader_set_uniform_1f (GstGLShader *shader, const gchar *name, gfloat value);
+void gst_gl_shader_set_uniform_1fv (GstGLShader *shader, const gchar *name, guint count, gfloat * value);
+
+G_END_DECLS
+
+#endif /* __GST_GL_SHADER_H__ */

gst/gl/Makefile.am

@@ -16,6 +16,8 @@ libgstopengl_la_SOURCES = \
 	gstglfiltercube.h \
 	gstglfilteredge.c \
 	gstglfilteredge.h \
+	gstglfilterlaplacian.c \
+	gstglfilterlaplacian.h \
 	gstglfilterapp.c \
 	gstglfilterapp.h \
 	gstglcolorscale.c \

gst/gl/gstglfilterlaplacian.c

@@ -0,0 +1,212 @@
+/* 
+ * GStreamer
+ * Copyright (C) 2008 Filippo Argiolas <filippo.argiolas@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gstglfilterlaplacian.h"
+
+#define GST_CAT_DEFAULT gst_gl_filter_laplacian_debug
+GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
+
+static const GstElementDetails element_details = 
+  GST_ELEMENT_DETAILS ("OpenGL laplacian filter",
+		       "Filter/Effect",
+		       "Laplacian Convolution Demo Filter",
+		       "Filippo Argiolas <filippo.argiolas@gmail.com>");
+
+enum
+{
+  PROP_0
+};
+
+#define DEBUG_INIT(bla)							\
+  GST_DEBUG_CATEGORY_INIT (gst_gl_filter_laplacian_debug, "glfilterlaplacian", 0, "glfilterlaplacian element");
+
+GST_BOILERPLATE_FULL (GstGLFilterLaplacian, gst_gl_filter_laplacian, GstGLFilter,
+		      GST_TYPE_GL_FILTER, DEBUG_INIT);
+
+static void gst_gl_filter_laplacian_set_property (GObject * object, guint prop_id,
+						  const GValue * value, GParamSpec * pspec);
+static void gst_gl_filter_laplacian_get_property (GObject * object, guint prop_id,
+						  GValue * value, GParamSpec * pspec);
+
+static void gst_gl_filter_laplacian_reset (GstGLFilter* filter);
+static void gst_gl_filter_laplacian_init_shader (GstGLFilter* filter);
+static gboolean gst_gl_filter_laplacian_filter (GstGLFilter * filter,
+						GstGLBuffer * inbuf, GstGLBuffer * outbuf);
+static void gst_gl_filter_laplacian_callback (gint width, gint height, guint texture, gpointer stuff);
+
+static const gchar *convolution_fragment_source = 
+  "#extension GL_ARB_texture_rectangle : enable\n"
+  "uniform sampler2DRect tex;"
+  "uniform float norm_const;"
+  "uniform float norm_offset;"
+  "uniform float kernel[9];"
+  "void main () {"
+  "  vec2 offset[9];"
+  "  offset = vec2[] ( vec2(-1.0,-1.0), vec2( 0.0,-1.0), vec2( 1.0,-1.0),"
+  "                    vec2(-1.0, 0.0), vec2( 0.0, 0.0), vec2( 1.0, 0.0),"
+  "                    vec2(-1.0, 1.0), vec2( 0.0, 1.0), vec2( 1.0, 1.0) );"
+  "  vec2 texturecoord = gl_TexCoord[0].st;"
+  "  int i;"
+  "  vec4 sum = vec4 (0.0);"
+  "  for (i = 0; i < 9; i++) { "
+  "    if (kernel[i] != 0.0) {"
+  "      vec4 neighbor = texture2DRect(tex, texturecoord + vec2(offset[i])); "
+  "      sum += neighbor * kernel[i]/norm_const; "
+  "    }"
+  "  }"
+  "  gl_FragColor = sum + norm_offset;"
+  "}";
+
+static void
+gst_gl_filter_laplacian_base_init (gpointer klass)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
+
+  gst_element_class_set_details (element_class, &element_details);
+}
+
+static void
+gst_gl_filter_laplacian_class_init (GstGLFilterLaplacianClass* klass)
+{
+  GObjectClass* gobject_class;
+
+  gobject_class = (GObjectClass *) klass;
+  gobject_class->set_property = gst_gl_filter_laplacian_set_property;
+  gobject_class->get_property = gst_gl_filter_laplacian_get_property;
+
+  GST_GL_FILTER_CLASS (klass)->filter = gst_gl_filter_laplacian_filter;
+  GST_GL_FILTER_CLASS (klass)->onInitFBO = gst_gl_filter_laplacian_init_shader;
+  GST_GL_FILTER_CLASS (klass)->onReset = gst_gl_filter_laplacian_reset;
+}
+
+static void
+gst_gl_filter_laplacian_init (GstGLFilterLaplacian* filter,
+    GstGLFilterLaplacianClass* klass)
+{
+}
+
+static void
+gst_gl_filter_laplacian_reset (GstGLFilter* filter)
+{
+  GstGLFilterLaplacian* laplacian_filter = GST_GL_FILTER_LAPLACIAN(filter);
+
+  //blocking call, wait the opengl thread has destroyed the shader program
+  g_object_unref (G_OBJECT (laplacian_filter->shader));
+}
+
+static void
+gst_gl_filter_laplacian_set_property (GObject* object, guint prop_id,
+				      const GValue* value, GParamSpec* pspec)
+{
+  //GstGLFilterLaplacian *filter = GST_GL_FILTER_LAPLACIAN (object);
+
+  switch (prop_id) 
+  {
+  default:
+    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    break;
+  }
+}
+
+static void
+gst_gl_filter_laplacian_get_property (GObject* object, guint prop_id,
+				      GValue* value, GParamSpec* pspec)
+{
+  //GstGLFilterLaplacian *filter = GST_GL_FILTER_LAPLACIAN (object);
+
+  switch (prop_id) 
+  {
+  default:
+    G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    break;
+  }
+}
+
+static void
+gst_gl_filter_laplacian_init_shader (GstGLFilter* filter)
+{
+//  GstGLFilterLaplacian* laplacian_filter = GST_GL_FILTER_LAPLACIAN (filter);
+    
+  // at the moment I do everything in the laplacian_callback
+}
+
+static gboolean
+gst_gl_filter_laplacian_filter (GstGLFilter* filter, GstGLBuffer* inbuf,
+				GstGLBuffer* outbuf)
+{
+  gpointer laplacian_filter = GST_GL_FILTER_LAPLACIAN (filter);
+    
+  //blocking call, generate a FBO
+  gst_gl_display_use_fbo (filter->display, filter->width, filter->height,
+			  filter->fbo, filter->depthbuffer, outbuf->texture, gst_gl_filter_laplacian_callback,
+			  inbuf->width, inbuf->height, inbuf->texture,
+			  0, filter->width, 0, filter->height,
+			  GST_GL_DISPLAY_PROJECTION_ORTHO2D, laplacian_filter);
+
+  return TRUE;
+}
+
+//opengl scene, params: input texture (not the output filter->texture)
+static void
+gst_gl_filter_laplacian_callback (gint width, gint height, guint texture, gpointer stuff)
+{
+  GstGLFilterLaplacian* laplacian_filter = GST_GL_FILTER_LAPLACIAN (stuff);
+
+  gfloat kernel[9] = {  0.0, -1.0,  0.0,
+		       -1.0,  4.0, -1.0,
+		        0.0, -1.0,  0.0  };
+    
+  glMatrixMode (GL_PROJECTION);
+  glLoadIdentity ();
+
+  /* compile and link the shader (if not done previously) */
+  if (!laplacian_filter->shader)
+    laplacian_filter->shader = gst_gl_shader_new ();
+  
+  g_return_if_fail (
+    gst_gl_shader_compile_and_check (laplacian_filter->shader, convolution_fragment_source,
+				     GST_GL_SHADER_FRAGMENT_SOURCE));
+  gst_gl_shader_use (laplacian_filter->shader);
+
+  glActiveTexture (GL_TEXTURE0);
+  glEnable (GL_TEXTURE_RECTANGLE_ARB);
+  glBindTexture (GL_TEXTURE_RECTANGLE_ARB, texture);
+
+  gst_gl_shader_set_uniform_1i  (laplacian_filter->shader, "tex", 0);
+  gst_gl_shader_set_uniform_1fv (laplacian_filter->shader, "kernel", 9, kernel);
+  gst_gl_shader_set_uniform_1f  (laplacian_filter->shader, "norm_const", 1.0);
+  gst_gl_shader_set_uniform_1f  (laplacian_filter->shader, "norm_offset", 0.0); //set to 0.5 to preserve overall greylevel
+  
+
+  glBegin (GL_QUADS);
+  glTexCoord2i (0, 0);
+  glVertex2f (-1.0f, -1.0f);
+  glTexCoord2i (width, 0);
+  glVertex2f (1.0f, -1.0f);
+  glTexCoord2i (width, height);
+  glVertex2f (1.0f, 1.0f);
+  glTexCoord2i (0, height);
+  glVertex2f (-1.0f, 1.0f);     
+  glEnd ();
+}

gst/gl/gstglfilterlaplacian.h

@@ -0,0 +1,54 @@
+/* 
+ * GStreamer
+ * Copyright (C) 2008 Filippo Argiolas <filippo.argiolas@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef _GST_GL_FILTERLAPLACIAN_H_
+#define _GST_GL_FILTERLAPLACIAN_H_
+
+#include <gstglfilter.h>
+#include <gstglshader.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_GL_FILTER_LAPLACIAN            (gst_gl_filter_laplacian_get_type())
+#define GST_GL_FILTER_LAPLACIAN(obj)            (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_GL_FILTER_LAPLACIAN,GstGLFilterLaplacian))
+#define GST_IS_GL_FILTER_LAPLACIAN(obj)         (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_GL_FILTER_LAPLACIAN))
+#define GST_GL_FILTER_LAPLACIAN_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST((klass) ,GST_TYPE_GL_FILTER_LAPLACIAN,GstGLFilterLaplacianClass))
+#define GST_IS_GL_FILTER_LAPLACIAN_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass) ,GST_TYPE_GL_FILTER_LAPLACIAN))
+#define GST_GL_FILTER_LAPLACIAN_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS((obj) ,GST_TYPE_GL_FILTER_LAPLACIAN,GstGLFilterLaplacianClass))
+
+typedef struct _GstGLFilterLaplacian GstGLFilterLaplacian;
+typedef struct _GstGLFilterLaplacianClass GstGLFilterLaplacianClass;
+
+struct _GstGLFilterLaplacian
+{
+  GstGLFilter filter;
+  GstGLShader *shader;
+};
+
+struct _GstGLFilterLaplacianClass
+{
+  GstGLFilterClass filter_class;
+};
+
+GType gst_gl_glfilterlaplacian_get_type (void);
+
+G_END_DECLS
+
+#endif /* _GST_GLFILTERLAPLACIAN_H_ */

gst/gl/gstopengl.c

@@ -26,6 +26,7 @@
 #include "gstglupload.h"
 #include "gstglfiltercube.h"
 #include "gstglfilteredge.h"
+#include "gstglfilterlaplacian.h"
 #include "gstglfilterapp.h"
 #include "gstgldownload.h"
 #include "gstglimagesink.h"
@@ -34,6 +35,7 @@
 GType gst_gl_filter_app_get_type (void);
 GType gst_gl_filter_cube_get_type (void);
 GType gst_gl_filter_edge_get_type (void);
+GType gst_gl_filter_laplacian_get_type (void);
 
 #define GST_CAT_DEFAULT gst_gl_gstgl_debug
 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
@@ -64,6 +66,11 @@ plugin_init (GstPlugin * plugin)
     return FALSE;
   }
 
+  if (!gst_element_register (plugin, "glfilterlaplacian",
+          GST_RANK_NONE, GST_TYPE_GL_FILTER_LAPLACIAN)) {
+    return FALSE;
+  }
+
   if (!gst_element_register (plugin, "glfilterapp",
           GST_RANK_NONE, GST_TYPE_GL_FILTER_APP)) {
     return FALSE;