ext/gl/gstglfiltercube.c - imx-gst-plugins-bad - Git at Google

 /*
  * GStreamer
  * Copyright (C) 2008 Julien Isorce <julien.isorce@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., 51 Franklin St, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */

 /**
  * SECTION:element-glfiltercube
  *
  * The resize and redraw callbacks can be set from a client code.
  *
  * <refsect2>
  * <title>Examples</title>
  * |[
  * gst-launch-1.0 -v videotestsrc ! glfiltercube ! glimagesink
  * ]| A pipeline to mpa textures on the 6 cube faces..
  * FBO is required.
  * |[
  * gst-launch-1.0 -v videotestsrc ! glfiltercube ! video/x-raw, width=640, height=480 ! glimagesink
  * ]| Resize scene after drawing the cube.
  * The scene size is greater than the input video size.
   |[
  * gst-launch-1.0 -v videotestsrc ! video/x-raw, width=640, height=480  ! glfiltercube ! glimagesink
  * ]| Resize scene before drawing the cube.
  * The scene size is greater than the input video size.
  * </refsect2>
  */

 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif

 #include <gst/gl/gstglapi.h>
 #include "gstglfiltercube.h"
 #include "gstglutils.h"

 #define GST_CAT_DEFAULT gst_gl_filter_cube_debug
 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);

 enum
 {
   PROP_0,
   PROP_RED,
   PROP_GREEN,
   PROP_BLUE,
   PROP_FOVY,
   PROP_ASPECT,
   PROP_ZNEAR,
   PROP_ZFAR
 };

 #define DEBUG_INIT \
     GST_DEBUG_CATEGORY_INIT (gst_gl_filter_cube_debug, "glfiltercube", 0, "glfiltercube element");
 #define gst_gl_filter_cube_parent_class parent_class
 G_DEFINE_TYPE_WITH_CODE (GstGLFilterCube, gst_gl_filter_cube,
     GST_TYPE_GL_FILTER, DEBUG_INIT);

 static void gst_gl_filter_cube_set_property (GObject * object, guint prop_id,
     const GValue * value, GParamSpec * pspec);
 static void gst_gl_filter_cube_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec);

 static gboolean gst_gl_filter_cube_set_caps (GstGLFilter * filter,
     GstCaps * incaps, GstCaps * outcaps);
 static gboolean gst_gl_filter_cube_gl_start (GstGLBaseFilter * 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);

 /* vertex source */
 static const gchar *cube_v_src =
     "attribute vec4 a_position;                                   \n"
     "attribute vec2 a_texcoord;                                   \n"
     "uniform mat4 u_matrix;                                       \n"
     "uniform float xrot_degree, yrot_degree, zrot_degree;         \n"
     "varying vec2 v_texcoord;                                     \n"
     "void main()                                                  \n"
     "{                                                            \n"
     "   float PI = 3.14159265;                                    \n"
     "   float xrot = xrot_degree*2.0*PI/360.0;                    \n"
     "   float yrot = yrot_degree*2.0*PI/360.0;                    \n"
     "   float zrot = zrot_degree*2.0*PI/360.0;                    \n"
     "   mat4 matX = mat4 (                                        \n"
     "            1.0,        0.0,        0.0, 0.0,                \n"
     "            0.0,  cos(xrot),  sin(xrot), 0.0,                \n"
     "            0.0, -sin(xrot),  cos(xrot), 0.0,                \n"
     "            0.0,        0.0,        0.0, 1.0 );              \n"
     "   mat4 matY = mat4 (                                        \n"
     "      cos(yrot),        0.0, -sin(yrot), 0.0,                \n"
     "            0.0,        1.0,        0.0, 0.0,                \n"
     "      sin(yrot),        0.0,  cos(yrot), 0.0,                \n"
     "            0.0,        0.0,       0.0,  1.0 );              \n"
     "   mat4 matZ = mat4 (                                        \n"
     "      cos(zrot),  sin(zrot),        0.0, 0.0,                \n"
     "     -sin(zrot),  cos(zrot),        0.0, 0.0,                \n"
     "            0.0,        0.0,        1.0, 0.0,                \n"
     "            0.0,        0.0,        0.0, 1.0 );              \n"
     "   gl_Position = u_matrix * matZ * matY * matX * a_position; \n"
     "   v_texcoord = a_texcoord;                                  \n"
     "}                                                            \n";

 /* fragment source */
 static const gchar *cube_f_src =
     "#ifdef GL_ES\n"
     "precision mediump float;\n"
     "#endif\n"
     "varying vec2 v_texcoord;                            \n"
     "uniform sampler2D s_texture;                        \n"
     "void main()                                         \n"
     "{                                                   \n"
     "  gl_FragColor = texture2D( s_texture, v_texcoord );\n"
     "}                                                   \n";

 static void
 gst_gl_filter_cube_class_init (GstGLFilterCubeClass * klass)
 {
   GObjectClass *gobject_class;
   GstElementClass *element_class;

   gobject_class = (GObjectClass *) klass;
   element_class = GST_ELEMENT_CLASS (klass);

   gobject_class->set_property = gst_gl_filter_cube_set_property;
   gobject_class->get_property = gst_gl_filter_cube_get_property;

   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)->set_caps = gst_gl_filter_cube_set_caps;
   GST_GL_FILTER_CLASS (klass)->filter_texture =
       gst_gl_filter_cube_filter_texture;

   g_object_class_install_property (gobject_class, PROP_RED,
       g_param_spec_float ("red", "Red", "Background red color",
           0.0f, 1.0f, 0.0f, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_GREEN,
       g_param_spec_float ("green", "Green", "Background green color",
           0.0f, 1.0f, 0.0f, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_BLUE,
       g_param_spec_float ("blue", "Blue", "Background blue color",
           0.0f, 1.0f, 0.0f, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_FOVY,
       g_param_spec_double ("fovy", "Fovy", "Field of view angle in degrees",
           0.0, 180.0, 45.0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_ASPECT,
       g_param_spec_double ("aspect", "Aspect",
           "Field of view in the x direction", 0.0, 100, 0.0,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_ZNEAR,
       g_param_spec_double ("znear", "Znear",
           "Specifies the distance from the viewer to the near clipping plane",
           0.0, 100.0, 0.1, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_ZFAR,
       g_param_spec_double ("zfar", "Zfar",
           "Specifies the distance from the viewer to the far clipping plane",
           0.0, 1000.0, 100.0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   gst_element_class_set_metadata (element_class, "OpenGL cube filter",
       "Filter/Effect/Video", "Map input texture on the 6 cube faces",
       "Julien Isorce <julien.isorce@gmail.com>");

   GST_GL_BASE_FILTER_CLASS (klass)->supported_gl_api =
       GST_GL_API_OPENGL | GST_GL_API_GLES2 | GST_GL_API_OPENGL3;
 }

 static void
 gst_gl_filter_cube_init (GstGLFilterCube * filter)
 {
   filter->shader = NULL;
   filter->fovy = 45;
   filter->aspect = 0;
   filter->znear = 0.1;
   filter->zfar = 100;
 }

 static void
 gst_gl_filter_cube_set_property (GObject * object, guint prop_id,
     const GValue * value, GParamSpec * pspec)
 {
   GstGLFilterCube *filter = GST_GL_FILTER_CUBE (object);

   switch (prop_id) {
     case PROP_RED:
       filter->red = g_value_get_float (value);
       break;
     case PROP_GREEN:
       filter->green = g_value_get_float (value);
       break;
     case PROP_BLUE:
       filter->blue = g_value_get_float (value);
       break;
     case PROP_FOVY:
       filter->fovy = g_value_get_double (value);
       break;
     case PROP_ASPECT:
       filter->aspect = g_value_get_double (value);
       break;
     case PROP_ZNEAR:
       filter->znear = g_value_get_double (value);
       break;
     case PROP_ZFAR:
       filter->zfar = g_value_get_double (value);
       break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
   }
 }

 static void
 gst_gl_filter_cube_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec)
 {
   GstGLFilterCube *filter = GST_GL_FILTER_CUBE (object);

   switch (prop_id) {
     case PROP_RED:
       g_value_set_float (value, filter->red);
       break;
     case PROP_GREEN:
       g_value_set_float (value, filter->green);
       break;
     case PROP_BLUE:
       g_value_set_float (value, filter->blue);
       break;
     case PROP_FOVY:
       g_value_set_double (value, filter->fovy);
       break;
     case PROP_ASPECT:
       g_value_set_double (value, filter->aspect);
       break;
     case PROP_ZNEAR:
       g_value_set_double (value, filter->znear);
       break;
     case PROP_ZFAR:
       g_value_set_double (value, filter->zfar);
       break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
   }
 }

 static gboolean
 gst_gl_filter_cube_set_caps (GstGLFilter * filter, GstCaps * incaps,
     GstCaps * outcaps)
 {
   GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (filter);

   if (cube_filter->aspect == 0)
     cube_filter->aspect = (gdouble) GST_VIDEO_INFO_WIDTH (&filter->out_info) /
         (gdouble) GST_VIDEO_INFO_HEIGHT (&filter->out_info);

   return TRUE;
 }

 static void
 gst_gl_filter_cube_gl_stop (GstGLBaseFilter * base_filter)
 {
   GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (base_filter);
   const GstGLFuncs *gl = base_filter->context->gl_vtable;

   if (cube_filter->vao) {
     gl->DeleteVertexArrays (1, &cube_filter->vao);
     cube_filter->vao = 0;
   }

   if (cube_filter->vertex_buffer) {
     gl->DeleteBuffers (1, &cube_filter->vertex_buffer);
     cube_filter->vertex_buffer = 0;
   }

   if (cube_filter->vbo_indices) {
     gl->DeleteBuffers (1, &cube_filter->vbo_indices);
     cube_filter->vbo_indices = 0;
   }

   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);
 }

 static gboolean
 gst_gl_filter_cube_filter_texture (GstGLFilter * filter, GstGLMemory * in_tex,
     GstGLMemory * out_tex)
 {
   GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (filter);

   cube_filter->in_tex = in_tex;

   return gst_gl_framebuffer_draw_to_texture (filter->fbo, out_tex, _callback,
       cube_filter);
 }

 /* *INDENT-OFF* */
 static const GLfloat vertices[] = {
  /*|     Vertex     | TexCoord |*/
     /* front face */
      1.0,  1.0, -1.0, 1.0, 0.0,
      1.0, -1.0, -1.0, 1.0, 1.0,
     -1.0, -1.0, -1.0, 0.0, 1.0,
     -1.0,  1.0, -1.0, 0.0, 0.0,
     /* back face */
      1.0,  1.0,  1.0, 1.0, 0.0,
     -1.0,  1.0,  1.0, 0.0, 0.0,
     -1.0, -1.0,  1.0, 0.0, 1.0,
      1.0, -1.0,  1.0, 1.0, 1.0,
     /* right face */
      1.0,  1.0,  1.0, 1.0, 0.0,
      1.0, -1.0,  1.0, 0.0, 0.0,
      1.0, -1.0, -1.0, 0.0, 1.0,
      1.0,  1.0, -1.0, 1.0, 1.0,
     /* left face */
     -1.0,  1.0,  1.0, 1.0, 0.0,
     -1.0,  1.0, -1.0, 1.0, 1.0,
     -1.0, -1.0, -1.0, 0.0, 1.0,
     -1.0, -1.0,  1.0, 0.0, 0.0,
     /* top face */
      1.0, -1.0,  1.0, 1.0, 0.0,
     -1.0, -1.0,  1.0, 0.0, 0.0,
     -1.0, -1.0, -1.0, 0.0, 1.0,
      1.0, -1.0, -1.0, 1.0, 1.0,
     /* bottom face */
      1.0,  1.0,  1.0, 1.0, 0.0,
      1.0,  1.0, -1.0, 1.0, 1.0,
     -1.0,  1.0, -1.0, 0.0, 1.0,
     -1.0,  1.0,  1.0, 0.0, 0.0
 };

 static const GLushort indices[] = {
     0, 1, 2,
     0, 2, 3,
     4, 5, 6,
     4, 6, 7,
     8, 9, 10,
     8, 10, 11,
     12, 13, 14,
     12, 14, 15,
     16, 17, 18,
     16, 18, 19,
     20, 21, 22,
     20, 22, 23
 };
 /* *INDENT-ON* */

 static void
 _bind_buffer (GstGLFilterCube * cube_filter)
 {
   const GstGLFuncs *gl = GST_GL_BASE_FILTER (cube_filter)->context->gl_vtable;

   gl->BindBuffer (GL_ELEMENT_ARRAY_BUFFER, cube_filter->vbo_indices);
   gl->BindBuffer (GL_ARRAY_BUFFER, cube_filter->vertex_buffer);

   cube_filter->attr_position =
       gst_gl_shader_get_attribute_location (cube_filter->shader, "a_position");

   cube_filter->attr_texture =
       gst_gl_shader_get_attribute_location (cube_filter->shader, "a_texcoord");

   /* Load the vertex position */
   gl->VertexAttribPointer (cube_filter->attr_position, 3, GL_FLOAT, GL_FALSE,
       5 * sizeof (GLfloat), (void *) 0);

   /* Load the texture coordinate */
   gl->VertexAttribPointer (cube_filter->attr_texture, 2, GL_FLOAT, GL_FALSE,
       5 * sizeof (GLfloat), (void *) (3 * sizeof (GLfloat)));

   gl->EnableVertexAttribArray (cube_filter->attr_position);
   gl->EnableVertexAttribArray (cube_filter->attr_texture);
 }

 static void
 _unbind_buffer (GstGLFilterCube * cube_filter)
 {
   const GstGLFuncs *gl = GST_GL_BASE_FILTER (cube_filter)->context->gl_vtable;

   gl->BindBuffer (GL_ELEMENT_ARRAY_BUFFER, 0);
   gl->BindBuffer (GL_ARRAY_BUFFER, 0);

   gl->DisableVertexAttribArray (cube_filter->attr_position);
   gl->DisableVertexAttribArray (cube_filter->attr_texture);
 }

 static gboolean
 _callback (gpointer stuff)
 {
   GstGLFilter *filter = GST_GL_FILTER (stuff);
   GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (filter);
   GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;

   static GLfloat xrot = 0;
   static GLfloat yrot = 0;
   static GLfloat zrot = 0;

   const GLfloat matrix[] = {
     0.5f, 0.0f, 0.0f, 0.0f,
     0.0f, 0.5f, 0.0f, 0.0f,
     0.0f, 0.0f, 0.5f, 0.0f,
     0.0f, 0.0f, 0.0f, 1.0f
   };

   gl->Enable (GL_DEPTH_TEST);

   gl->ClearColor (cube_filter->red, cube_filter->green, cube_filter->blue, 0.0);
   gl->Clear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

   gst_gl_shader_use (cube_filter->shader);

   gl->ActiveTexture (GL_TEXTURE0);
   gl->BindTexture (GL_TEXTURE_2D, cube_filter->in_tex->tex_id);
   gst_gl_shader_set_uniform_1i (cube_filter->shader, "s_texture", 0);
   gst_gl_shader_set_uniform_1f (cube_filter->shader, "xrot_degree", xrot);
   gst_gl_shader_set_uniform_1f (cube_filter->shader, "yrot_degree", yrot);
   gst_gl_shader_set_uniform_1f (cube_filter->shader, "zrot_degree", zrot);
   gst_gl_shader_set_uniform_matrix_4fv (cube_filter->shader, "u_matrix", 1,
       GL_FALSE, matrix);

   if (!cube_filter->vertex_buffer) {
     if (gl->GenVertexArrays) {
       gl->GenVertexArrays (1, &cube_filter->vao);
       gl->BindVertexArray (cube_filter->vao);
     }

     gl->GenBuffers (1, &cube_filter->vertex_buffer);
     gl->BindBuffer (GL_ARRAY_BUFFER, cube_filter->vertex_buffer);
     gl->BufferData (GL_ARRAY_BUFFER, 6 * 4 * 5 * sizeof (GLfloat), vertices,
         GL_STATIC_DRAW);

     gl->GenBuffers (1, &cube_filter->vbo_indices);
     gl->BindBuffer (GL_ELEMENT_ARRAY_BUFFER, cube_filter->vbo_indices);
     gl->BufferData (GL_ELEMENT_ARRAY_BUFFER, sizeof (indices), indices,
         GL_STATIC_DRAW);

     if (gl->GenVertexArrays) {
       _bind_buffer (cube_filter);
       gl->BindVertexArray (0);
     }

     gl->BindBuffer (GL_ELEMENT_ARRAY_BUFFER, 0);
     gl->BindBuffer (GL_ARRAY_BUFFER, 0);
   }

   if (gl->GenVertexArrays)
     gl->BindVertexArray (cube_filter->vao);
   _bind_buffer (cube_filter);

   gl->DrawElements (GL_TRIANGLES, 36, GL_UNSIGNED_SHORT, 0);

   if (gl->GenVertexArrays)
     gl->BindVertexArray (0);
   _unbind_buffer (cube_filter);

   gl->Disable (GL_DEPTH_TEST);

   xrot += 0.3f;
   yrot += 0.2f;
   zrot += 0.4f;

   return TRUE;
 }
	/*
	* GStreamer
	* Copyright (C) 2008 Julien Isorce <julien.isorce@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., 51 Franklin St, Fifth Floor,
	* Boston, MA 02110-1301, USA.
	*/

	/**
	* SECTION:element-glfiltercube
	*
	* The resize and redraw callbacks can be set from a client code.
	*
	* <refsect2>
	* <title>Examples</title>
	* \|[
	* gst-launch-1.0 -v videotestsrc ! glfiltercube ! glimagesink
	* ]\| A pipeline to mpa textures on the 6 cube faces..
	* FBO is required.
	* \|[
	* gst-launch-1.0 -v videotestsrc ! glfiltercube ! video/x-raw, width=640, height=480 ! glimagesink
	* ]\| Resize scene after drawing the cube.
	* The scene size is greater than the input video size.
	\|[
	* gst-launch-1.0 -v videotestsrc ! video/x-raw, width=640, height=480 ! glfiltercube ! glimagesink
	* ]\| Resize scene before drawing the cube.
	* The scene size is greater than the input video size.
	* </refsect2>
	*/

	#ifdef HAVE_CONFIG_H
	#include "config.h"
	#endif

	#include <gst/gl/gstglapi.h>
	#include "gstglfiltercube.h"
	#include "gstglutils.h"

	#define GST_CAT_DEFAULT gst_gl_filter_cube_debug
	GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);

	enum
	{
	PROP_0,
	PROP_RED,
	PROP_GREEN,
	PROP_BLUE,
	PROP_FOVY,
	PROP_ASPECT,
	PROP_ZNEAR,
	PROP_ZFAR
	};

	#define DEBUG_INIT \
	GST_DEBUG_CATEGORY_INIT (gst_gl_filter_cube_debug, "glfiltercube", 0, "glfiltercube element");
	#define gst_gl_filter_cube_parent_class parent_class
	G_DEFINE_TYPE_WITH_CODE (GstGLFilterCube, gst_gl_filter_cube,
	GST_TYPE_GL_FILTER, DEBUG_INIT);

	static void gst_gl_filter_cube_set_property (GObject * object, guint prop_id,
	const GValue * value, GParamSpec * pspec);
	static void gst_gl_filter_cube_get_property (GObject * object, guint prop_id,
	GValue * value, GParamSpec * pspec);

	static gboolean gst_gl_filter_cube_set_caps (GstGLFilter * filter,
	GstCaps * incaps, GstCaps * outcaps);
	static gboolean gst_gl_filter_cube_gl_start (GstGLBaseFilter * 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);

	/* vertex source */
	static const gchar *cube_v_src =
	"attribute vec4 a_position; \n"
	"attribute vec2 a_texcoord; \n"
	"uniform mat4 u_matrix; \n"
	"uniform float xrot_degree, yrot_degree, zrot_degree; \n"
	"varying vec2 v_texcoord; \n"
	"void main() \n"
	"{ \n"
	" float PI = 3.14159265; \n"
	" float xrot = xrot_degree2.0PI/360.0; \n"
	" float yrot = yrot_degree2.0PI/360.0; \n"
	" float zrot = zrot_degree2.0PI/360.0; \n"
	" mat4 matX = mat4 ( \n"
	" 1.0, 0.0, 0.0, 0.0, \n"
	" 0.0, cos(xrot), sin(xrot), 0.0, \n"
	" 0.0, -sin(xrot), cos(xrot), 0.0, \n"
	" 0.0, 0.0, 0.0, 1.0 ); \n"
	" mat4 matY = mat4 ( \n"
	" cos(yrot), 0.0, -sin(yrot), 0.0, \n"
	" 0.0, 1.0, 0.0, 0.0, \n"
	" sin(yrot), 0.0, cos(yrot), 0.0, \n"
	" 0.0, 0.0, 0.0, 1.0 ); \n"
	" mat4 matZ = mat4 ( \n"
	" cos(zrot), sin(zrot), 0.0, 0.0, \n"
	" -sin(zrot), cos(zrot), 0.0, 0.0, \n"
	" 0.0, 0.0, 1.0, 0.0, \n"
	" 0.0, 0.0, 0.0, 1.0 ); \n"
	" gl_Position = u_matrix * matZ * matY * matX * a_position; \n"
	" v_texcoord = a_texcoord; \n"
	"} \n";

	/* fragment source */
	static const gchar *cube_f_src =
	"#ifdef GL_ES\n"
	"precision mediump float;\n"
	"#endif\n"
	"varying vec2 v_texcoord; \n"
	"uniform sampler2D s_texture; \n"
	"void main() \n"
	"{ \n"
	" gl_FragColor = texture2D( s_texture, v_texcoord );\n"
	"} \n";

	static void
	gst_gl_filter_cube_class_init (GstGLFilterCubeClass * klass)
	{
	GObjectClass *gobject_class;
	GstElementClass *element_class;

	gobject_class = (GObjectClass *) klass;
	element_class = GST_ELEMENT_CLASS (klass);

	gobject_class->set_property = gst_gl_filter_cube_set_property;
	gobject_class->get_property = gst_gl_filter_cube_get_property;

	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)->set_caps = gst_gl_filter_cube_set_caps;
	GST_GL_FILTER_CLASS (klass)->filter_texture =
	gst_gl_filter_cube_filter_texture;

	g_object_class_install_property (gobject_class, PROP_RED,
	g_param_spec_float ("red", "Red", "Background red color",
	0.0f, 1.0f, 0.0f, G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_GREEN,
	g_param_spec_float ("green", "Green", "Background green color",
	0.0f, 1.0f, 0.0f, G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_BLUE,
	g_param_spec_float ("blue", "Blue", "Background blue color",
	0.0f, 1.0f, 0.0f, G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_FOVY,
	g_param_spec_double ("fovy", "Fovy", "Field of view angle in degrees",
	0.0, 180.0, 45.0, G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_ASPECT,
	g_param_spec_double ("aspect", "Aspect",
	"Field of view in the x direction", 0.0, 100, 0.0,
	G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_ZNEAR,
	g_param_spec_double ("znear", "Znear",
	"Specifies the distance from the viewer to the near clipping plane",
	0.0, 100.0, 0.1, G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_ZFAR,
	g_param_spec_double ("zfar", "Zfar",
	"Specifies the distance from the viewer to the far clipping plane",
	0.0, 1000.0, 100.0, G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	gst_element_class_set_metadata (element_class, "OpenGL cube filter",
	"Filter/Effect/Video", "Map input texture on the 6 cube faces",
	"Julien Isorce <julien.isorce@gmail.com>");

	GST_GL_BASE_FILTER_CLASS (klass)->supported_gl_api =
	GST_GL_API_OPENGL \| GST_GL_API_GLES2 \| GST_GL_API_OPENGL3;
	}

	static void
	gst_gl_filter_cube_init (GstGLFilterCube * filter)
	{
	filter->shader = NULL;
	filter->fovy = 45;
	filter->aspect = 0;
	filter->znear = 0.1;
	filter->zfar = 100;
	}

	static void
	gst_gl_filter_cube_set_property (GObject * object, guint prop_id,
	const GValue * value, GParamSpec * pspec)
	{
	GstGLFilterCube *filter = GST_GL_FILTER_CUBE (object);

	switch (prop_id) {
	case PROP_RED:
	filter->red = g_value_get_float (value);
	break;
	case PROP_GREEN:
	filter->green = g_value_get_float (value);
	break;
	case PROP_BLUE:
	filter->blue = g_value_get_float (value);
	break;
	case PROP_FOVY:
	filter->fovy = g_value_get_double (value);
	break;
	case PROP_ASPECT:
	filter->aspect = g_value_get_double (value);
	break;
	case PROP_ZNEAR:
	filter->znear = g_value_get_double (value);
	break;
	case PROP_ZFAR:
	filter->zfar = g_value_get_double (value);
	break;
	default:
	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
	break;
	}
	}

	static void
	gst_gl_filter_cube_get_property (GObject * object, guint prop_id,
	GValue * value, GParamSpec * pspec)
	{
	GstGLFilterCube *filter = GST_GL_FILTER_CUBE (object);

	switch (prop_id) {
	case PROP_RED:
	g_value_set_float (value, filter->red);
	break;
	case PROP_GREEN:
	g_value_set_float (value, filter->green);
	break;
	case PROP_BLUE:
	g_value_set_float (value, filter->blue);
	break;
	case PROP_FOVY:
	g_value_set_double (value, filter->fovy);
	break;
	case PROP_ASPECT:
	g_value_set_double (value, filter->aspect);
	break;
	case PROP_ZNEAR:
	g_value_set_double (value, filter->znear);
	break;
	case PROP_ZFAR:
	g_value_set_double (value, filter->zfar);
	break;
	default:
	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
	break;
	}
	}

	static gboolean
	gst_gl_filter_cube_set_caps (GstGLFilter * filter, GstCaps * incaps,
	GstCaps * outcaps)
	{
	GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (filter);

	if (cube_filter->aspect == 0)
	cube_filter->aspect = (gdouble) GST_VIDEO_INFO_WIDTH (&filter->out_info) /
	(gdouble) GST_VIDEO_INFO_HEIGHT (&filter->out_info);

	return TRUE;
	}

	static void
	gst_gl_filter_cube_gl_stop (GstGLBaseFilter * base_filter)
	{
	GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (base_filter);
	const GstGLFuncs *gl = base_filter->context->gl_vtable;

	if (cube_filter->vao) {
	gl->DeleteVertexArrays (1, &cube_filter->vao);
	cube_filter->vao = 0;
	}

	if (cube_filter->vertex_buffer) {
	gl->DeleteBuffers (1, &cube_filter->vertex_buffer);
	cube_filter->vertex_buffer = 0;
	}

	if (cube_filter->vbo_indices) {
	gl->DeleteBuffers (1, &cube_filter->vbo_indices);
	cube_filter->vbo_indices = 0;
	}

	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);
	}

	static gboolean
	gst_gl_filter_cube_filter_texture (GstGLFilter * filter, GstGLMemory * in_tex,
	GstGLMemory * out_tex)
	{
	GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (filter);

	cube_filter->in_tex = in_tex;

	return gst_gl_framebuffer_draw_to_texture (filter->fbo, out_tex, _callback,
	cube_filter);
	}

	/* INDENT-OFF */
	static const GLfloat vertices[] = {
	/\| Vertex \| TexCoord \|/
	/* front face */
	1.0, 1.0, -1.0, 1.0, 0.0,
	1.0, -1.0, -1.0, 1.0, 1.0,
	-1.0, -1.0, -1.0, 0.0, 1.0,
	-1.0, 1.0, -1.0, 0.0, 0.0,
	/* back face */
	1.0, 1.0, 1.0, 1.0, 0.0,
	-1.0, 1.0, 1.0, 0.0, 0.0,
	-1.0, -1.0, 1.0, 0.0, 1.0,
	1.0, -1.0, 1.0, 1.0, 1.0,
	/* right face */
	1.0, 1.0, 1.0, 1.0, 0.0,
	1.0, -1.0, 1.0, 0.0, 0.0,
	1.0, -1.0, -1.0, 0.0, 1.0,
	1.0, 1.0, -1.0, 1.0, 1.0,
	/* left face */
	-1.0, 1.0, 1.0, 1.0, 0.0,
	-1.0, 1.0, -1.0, 1.0, 1.0,
	-1.0, -1.0, -1.0, 0.0, 1.0,
	-1.0, -1.0, 1.0, 0.0, 0.0,
	/* top face */
	1.0, -1.0, 1.0, 1.0, 0.0,
	-1.0, -1.0, 1.0, 0.0, 0.0,
	-1.0, -1.0, -1.0, 0.0, 1.0,
	1.0, -1.0, -1.0, 1.0, 1.0,
	/* bottom face */
	1.0, 1.0, 1.0, 1.0, 0.0,
	1.0, 1.0, -1.0, 1.0, 1.0,
	-1.0, 1.0, -1.0, 0.0, 1.0,
	-1.0, 1.0, 1.0, 0.0, 0.0
	};

	static const GLushort indices[] = {
	0, 1, 2,
	0, 2, 3,
	4, 5, 6,
	4, 6, 7,
	8, 9, 10,
	8, 10, 11,
	12, 13, 14,
	12, 14, 15,
	16, 17, 18,
	16, 18, 19,
	20, 21, 22,
	20, 22, 23
	};
	/* INDENT-ON */

	static void
	_bind_buffer (GstGLFilterCube * cube_filter)
	{
	const GstGLFuncs *gl = GST_GL_BASE_FILTER (cube_filter)->context->gl_vtable;

	gl->BindBuffer (GL_ELEMENT_ARRAY_BUFFER, cube_filter->vbo_indices);
	gl->BindBuffer (GL_ARRAY_BUFFER, cube_filter->vertex_buffer);

	cube_filter->attr_position =
	gst_gl_shader_get_attribute_location (cube_filter->shader, "a_position");

	cube_filter->attr_texture =
	gst_gl_shader_get_attribute_location (cube_filter->shader, "a_texcoord");

	/* Load the vertex position */
	gl->VertexAttribPointer (cube_filter->attr_position, 3, GL_FLOAT, GL_FALSE,
	5 * sizeof (GLfloat), (void *) 0);

	/* Load the texture coordinate */
	gl->VertexAttribPointer (cube_filter->attr_texture, 2, GL_FLOAT, GL_FALSE,
	5 * sizeof (GLfloat), (void ) (3 sizeof (GLfloat)));

	gl->EnableVertexAttribArray (cube_filter->attr_position);
	gl->EnableVertexAttribArray (cube_filter->attr_texture);
	}

	static void
	_unbind_buffer (GstGLFilterCube * cube_filter)
	{
	const GstGLFuncs *gl = GST_GL_BASE_FILTER (cube_filter)->context->gl_vtable;

	gl->BindBuffer (GL_ELEMENT_ARRAY_BUFFER, 0);
	gl->BindBuffer (GL_ARRAY_BUFFER, 0);

	gl->DisableVertexAttribArray (cube_filter->attr_position);
	gl->DisableVertexAttribArray (cube_filter->attr_texture);
	}

	static gboolean
	_callback (gpointer stuff)
	{
	GstGLFilter *filter = GST_GL_FILTER (stuff);
	GstGLFilterCube *cube_filter = GST_GL_FILTER_CUBE (filter);
	GstGLFuncs *gl = GST_GL_BASE_FILTER (filter)->context->gl_vtable;

	static GLfloat xrot = 0;
	static GLfloat yrot = 0;
	static GLfloat zrot = 0;

	const GLfloat matrix[] = {
	0.5f, 0.0f, 0.0f, 0.0f,
	0.0f, 0.5f, 0.0f, 0.0f,
	0.0f, 0.0f, 0.5f, 0.0f,
	0.0f, 0.0f, 0.0f, 1.0f
	};

	gl->Enable (GL_DEPTH_TEST);

	gl->ClearColor (cube_filter->red, cube_filter->green, cube_filter->blue, 0.0);
	gl->Clear (GL_COLOR_BUFFER_BIT \| GL_DEPTH_BUFFER_BIT);

	gst_gl_shader_use (cube_filter->shader);

	gl->ActiveTexture (GL_TEXTURE0);
	gl->BindTexture (GL_TEXTURE_2D, cube_filter->in_tex->tex_id);
	gst_gl_shader_set_uniform_1i (cube_filter->shader, "s_texture", 0);
	gst_gl_shader_set_uniform_1f (cube_filter->shader, "xrot_degree", xrot);
	gst_gl_shader_set_uniform_1f (cube_filter->shader, "yrot_degree", yrot);
	gst_gl_shader_set_uniform_1f (cube_filter->shader, "zrot_degree", zrot);
	gst_gl_shader_set_uniform_matrix_4fv (cube_filter->shader, "u_matrix", 1,
	GL_FALSE, matrix);

	if (!cube_filter->vertex_buffer) {
	if (gl->GenVertexArrays) {
	gl->GenVertexArrays (1, &cube_filter->vao);
	gl->BindVertexArray (cube_filter->vao);
	}

	gl->GenBuffers (1, &cube_filter->vertex_buffer);
	gl->BindBuffer (GL_ARRAY_BUFFER, cube_filter->vertex_buffer);
	gl->BufferData (GL_ARRAY_BUFFER, 6 * 4 * 5 * sizeof (GLfloat), vertices,
	GL_STATIC_DRAW);

	gl->GenBuffers (1, &cube_filter->vbo_indices);
	gl->BindBuffer (GL_ELEMENT_ARRAY_BUFFER, cube_filter->vbo_indices);
	gl->BufferData (GL_ELEMENT_ARRAY_BUFFER, sizeof (indices), indices,
	GL_STATIC_DRAW);

	if (gl->GenVertexArrays) {
	_bind_buffer (cube_filter);
	gl->BindVertexArray (0);
	}

	gl->BindBuffer (GL_ELEMENT_ARRAY_BUFFER, 0);
	gl->BindBuffer (GL_ARRAY_BUFFER, 0);
	}

	if (gl->GenVertexArrays)
	gl->BindVertexArray (cube_filter->vao);
	_bind_buffer (cube_filter);

	gl->DrawElements (GL_TRIANGLES, 36, GL_UNSIGNED_SHORT, 0);

	if (gl->GenVertexArrays)
	gl->BindVertexArray (0);
	_unbind_buffer (cube_filter);

	gl->Disable (GL_DEPTH_TEST);

	xrot += 0.3f;
	yrot += 0.2f;
	zrot += 0.4f;

	return TRUE;
	}