ext/gl/gstgltransformation.c - mtk-gst-plugins-bad-debian - Git at Google

 /*
  * GStreamer
  * Copyright (C) 2014 Lubosz Sarnecki <lubosz@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-gltransformation
  *
  * Transforms video on the GPU.
  *
  * <refsect2>
  * <title>Examples</title>
  * |[
  * gst-launch gltestsrc ! gltransformation rotation-z=45 ! glimagesink
  * ]| A pipeline to rotate by 45 degrees
  * |[
  * gst-launch gltestsrc ! gltransformation translation-x=0.5 ! glimagesink
  * ]| Translate the video by 0.5
  * |[
  * gst-launch gltestsrc ! gltransformation scale-y=0.5 scale-x=0.5 ! glimagesink
  * ]| Resize the video by 0.5
  * |[
  * gst-launch gltestsrc ! gltransformation rotation-x=-45 ortho=True ! glimagesink
  * ]| Rotate the video around the X-Axis by -45° with an orthographic projection
  * </refsect2>
  */

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

 #include <gst/gl/gstglapi.h>
 #include "gstgltransformation.h"

 #define GST_CAT_DEFAULT gst_gl_transformation_debug
 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);

 enum
 {
   PROP_0,
   PROP_FOVY,
   PROP_ORTHO,
   PROP_TRANSLATION_X,
   PROP_TRANSLATION_Y,
   PROP_TRANSLATION_Z,
   PROP_ROTATION_X,
   PROP_ROTATION_Y,
   PROP_ROTATION_Z,
   PROP_SCALE_X,
   PROP_SCALE_Y
 };

 #define DEBUG_INIT \
     GST_DEBUG_CATEGORY_INIT (gst_gl_transformation_debug, "gltransformation", 0, "gltransformation element");

 G_DEFINE_TYPE_WITH_CODE (GstGLTransformation, gst_gl_transformation,
     GST_TYPE_GL_FILTER, DEBUG_INIT);

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

 static gboolean gst_gl_transformation_set_caps (GstGLFilter * filter,
     GstCaps * incaps, GstCaps * outcaps);

 static void gst_gl_transformation_reset (GstGLFilter * filter);
 static gboolean gst_gl_transformation_init_shader (GstGLFilter * filter);
 static void gst_gl_transformation_callback (gpointer stuff);
 static void gst_gl_transformation_build_mvp (GstGLTransformation *
     transformation);

 static gboolean gst_gl_transformation_filter_texture (GstGLFilter * filter,
     guint in_tex, guint out_tex);

 /* vertex source */
 static const gchar *cube_v_src =
     "attribute vec4 position;                     \n"
     "attribute vec2 uv;                           \n"
     "uniform mat4 mvp;                            \n"
     "varying vec2 out_uv;                         \n"
     "void main()                                  \n"
     "{                                            \n"
     "   gl_Position = mvp * position;             \n"
     "   out_uv = uv;                              \n"
     "}                                            \n";

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

 static void
 gst_gl_transformation_class_init (GstGLTransformationClass * klass)
 {
   GObjectClass *gobject_class;
   GstElementClass *element_class;

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

   gobject_class->set_property = gst_gl_transformation_set_property;
   gobject_class->get_property = gst_gl_transformation_get_property;

   GST_GL_FILTER_CLASS (klass)->onInitFBO = gst_gl_transformation_init_shader;
   GST_GL_FILTER_CLASS (klass)->onReset = gst_gl_transformation_reset;
   GST_GL_FILTER_CLASS (klass)->set_caps = gst_gl_transformation_set_caps;
   GST_GL_FILTER_CLASS (klass)->filter_texture =
       gst_gl_transformation_filter_texture;

   g_object_class_install_property (gobject_class, PROP_FOVY,
       g_param_spec_float ("fovy", "Fovy", "Field of view angle in degrees",
           0.0, G_MAXFLOAT, 90.0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_ORTHO,
       g_param_spec_boolean ("ortho", "Orthographic",
           "Use orthographic projection", FALSE,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   /* Rotation */
   g_object_class_install_property (gobject_class, PROP_ROTATION_X,
       g_param_spec_float ("rotation-x", "X Rotation",
           "Rotates the video around the X-Axis in degrees.",
           -G_MAXFLOAT, G_MAXFLOAT, 0.0,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_ROTATION_Y,
       g_param_spec_float ("rotation-y", "Y Rotation",
           "Rotates the video around the Y-Axis in degrees.",
           -G_MAXFLOAT, G_MAXFLOAT, 0.0,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_ROTATION_Z,
       g_param_spec_float ("rotation-z", "Z Rotation",
           "Rotates the video around the Z-Axis in degrees.",
           -G_MAXFLOAT, G_MAXFLOAT, 0.0,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   /* Translation */
   g_object_class_install_property (gobject_class, PROP_TRANSLATION_X,
       g_param_spec_float ("translation-x", "X Translation",
           "Translates the video at the X-Axis.",
           -G_MAXFLOAT, G_MAXFLOAT, 0.0,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_TRANSLATION_Y,
       g_param_spec_float ("translation-y", "Y Translation",
           "Translates the video at the Y-Axis.",
           -G_MAXFLOAT, G_MAXFLOAT, 0.0,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_TRANSLATION_Z,
       g_param_spec_float ("translation-z", "Z Translation",
           "Translates the video at the Z-Axis.",
           -G_MAXFLOAT, G_MAXFLOAT, 0.0,
           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   /* Scale */
   g_object_class_install_property (gobject_class, PROP_SCALE_X,
       g_param_spec_float ("scale-x", "X Scale",
           "Scale multiplierer for the X-Axis.",
           0.0, G_MAXFLOAT, 1.0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   g_object_class_install_property (gobject_class, PROP_SCALE_Y,
       g_param_spec_float ("scale-y", "Y Scale",
           "Scale multiplierer for the Y-Axis.",
           0.0, G_MAXFLOAT, 1.0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

   gst_element_class_set_metadata (element_class, "OpenGL transformation filter",
       "Filter/Effect/Video", "Transform video on the GPU",
       "Lubosz Sarnecki <lubosz@gmail.com>");
 }

 static void
 gst_gl_transformation_init (GstGLTransformation * filter)
 {
   filter->shader = NULL;
   filter->fovy = 90;
   filter->aspect = 0;
   filter->znear = 0.1;
   filter->zfar = 100;

   filter->xscale = 1.0;
   filter->yscale = 1.0;

   filter->in_tex = 0;

   gst_gl_transformation_build_mvp (filter);
 }

 static void
 gst_gl_transformation_build_mvp (GstGLTransformation * transformation)
 {
   graphene_point3d_t translation_vector =
       GRAPHENE_POINT3D_INIT (transformation->xtranslation,
       transformation->ytranslation,
       transformation->ztranslation);

   graphene_matrix_t model_matrix;
   graphene_matrix_t projection_matrix;
   graphene_matrix_t view_matrix;
   graphene_matrix_t vp_matrix;

   graphene_vec3_t eye;
   graphene_vec3_t center;
   graphene_vec3_t up;

   graphene_vec3_init (&eye, 0.f, 0.f, 1.f);
   graphene_vec3_init (&center, 0.f, 0.f, 0.f);
   graphene_vec3_init (&up, 0.f, 1.f, 0.f);

   graphene_matrix_init_rotate (&model_matrix,
       transformation->xrotation, graphene_vec3_x_axis ());
   graphene_matrix_rotate (&model_matrix,
       transformation->yrotation, graphene_vec3_y_axis ());
   graphene_matrix_rotate (&model_matrix,
       transformation->zrotation, graphene_vec3_z_axis ());
   graphene_matrix_scale (&model_matrix,
       transformation->xscale, transformation->yscale, 1.0f);
   graphene_matrix_translate (&model_matrix, &translation_vector);

   if (transformation->ortho) {
     graphene_matrix_init_ortho (&projection_matrix,
         -transformation->aspect, transformation->aspect,
         -1, 1, transformation->znear, transformation->zfar);
   } else {
     graphene_matrix_init_perspective (&projection_matrix,
         transformation->fovy,
         transformation->aspect, transformation->znear, transformation->zfar);
   }

   graphene_matrix_init_look_at (&view_matrix, &eye, &center, &up);

   graphene_matrix_multiply (&view_matrix, &projection_matrix, &vp_matrix);
   graphene_matrix_multiply (&model_matrix, &vp_matrix,
       &transformation->mvp_matrix);
 }

 static void
 gst_gl_transformation_set_property (GObject * object, guint prop_id,
     const GValue * value, GParamSpec * pspec)
 {
   GstGLTransformation *filter = GST_GL_TRANSFORMATION (object);

   switch (prop_id) {
     case PROP_FOVY:
       filter->fovy = g_value_get_float (value);
       break;
     case PROP_ORTHO:
       filter->ortho = g_value_get_boolean (value);
       break;
     case PROP_TRANSLATION_X:
       filter->xtranslation = g_value_get_float (value);
       break;
     case PROP_TRANSLATION_Y:
       filter->ytranslation = g_value_get_float (value);
       break;
     case PROP_TRANSLATION_Z:
       filter->ztranslation = g_value_get_float (value);
       break;
     case PROP_ROTATION_X:
       filter->xrotation = g_value_get_float (value);
       break;
     case PROP_ROTATION_Y:
       filter->yrotation = g_value_get_float (value);
       break;
     case PROP_ROTATION_Z:
       filter->zrotation = g_value_get_float (value);
       break;
     case PROP_SCALE_X:
       filter->xscale = g_value_get_float (value);
       break;
     case PROP_SCALE_Y:
       filter->yscale = g_value_get_float (value);
       break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
   }
   gst_gl_transformation_build_mvp (filter);
 }

 static void
 gst_gl_transformation_get_property (GObject * object, guint prop_id,
     GValue * value, GParamSpec * pspec)
 {
   GstGLTransformation *filter = GST_GL_TRANSFORMATION (object);

   switch (prop_id) {
     case PROP_FOVY:
       g_value_set_float (value, filter->fovy);
       break;
     case PROP_ORTHO:
       g_value_set_boolean (value, filter->ortho);
       break;
     case PROP_TRANSLATION_X:
       g_value_set_float (value, filter->xtranslation);
       break;
     case PROP_TRANSLATION_Y:
       g_value_set_float (value, filter->ytranslation);
       break;
     case PROP_TRANSLATION_Z:
       g_value_set_float (value, filter->ztranslation);
       break;
     case PROP_ROTATION_X:
       g_value_set_float (value, filter->xrotation);
       break;
     case PROP_ROTATION_Y:
       g_value_set_float (value, filter->yrotation);
       break;
     case PROP_ROTATION_Z:
       g_value_set_float (value, filter->zrotation);
       break;
     case PROP_SCALE_X:
       g_value_set_float (value, filter->xscale);
       break;
     case PROP_SCALE_Y:
       g_value_set_float (value, filter->yscale);
       break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
   }
 }

 static gboolean
 gst_gl_transformation_set_caps (GstGLFilter * filter, GstCaps * incaps,
     GstCaps * outcaps)
 {
   GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);

   transformation->aspect =
       (gdouble) GST_VIDEO_INFO_WIDTH (&filter->out_info) /
       (gdouble) GST_VIDEO_INFO_HEIGHT (&filter->out_info);

   gst_gl_transformation_build_mvp (transformation);

   return TRUE;
 }

 static void
 gst_gl_transformation_reset (GstGLFilter * filter)
 {
   GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);

   /* blocking call, wait until the opengl thread has destroyed the shader */
   if (transformation->shader)
     gst_gl_context_del_shader (filter->context, transformation->shader);
   transformation->shader = NULL;
 }

 static gboolean
 gst_gl_transformation_init_shader (GstGLFilter * filter)
 {
   GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);

   if (gst_gl_context_get_gl_api (filter->context)) {
     /* blocking call, wait until the opengl thread has compiled the shader */
     return gst_gl_context_gen_shader (filter->context, cube_v_src, cube_f_src,
         &transformation->shader);
   }
   return TRUE;
 }

 static gboolean
 gst_gl_transformation_filter_texture (GstGLFilter * filter, guint in_tex,
     guint out_tex)
 {
   GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);

   transformation->in_tex = in_tex;

   /* blocking call, use a FBO */
   gst_gl_context_use_fbo_v2 (filter->context,
       GST_VIDEO_INFO_WIDTH (&filter->out_info),
       GST_VIDEO_INFO_HEIGHT (&filter->out_info),
       filter->fbo, filter->depthbuffer,
       out_tex, gst_gl_transformation_callback, (gpointer) transformation);

   return TRUE;
 }

 static void
 gst_gl_transformation_callback (gpointer stuff)
 {
   GstGLFilter *filter = GST_GL_FILTER (stuff);
   GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);
   GstGLFuncs *gl = filter->context->gl_vtable;

 /* *INDENT-OFF* */

   const GLfloat positions[] = {
      -transformation->aspect,  1.0,  0.0, 1.0,
       transformation->aspect,  1.0,  0.0, 1.0,
       transformation->aspect, -1.0,  0.0, 1.0,
      -transformation->aspect, -1.0,  0.0, 1.0,
   };

   const GLfloat texture_coordinates[] = {
      0.0,  1.0,
      1.0,  1.0,
      1.0,  0.0,
      0.0,  0.0,
   };

 /* *INDENT-ON* */

   GLushort indices[] = { 0, 1, 2, 3, 0 };

   GLfloat temp_matrix[16];

   GLint attr_position_loc = 0;
   GLint attr_texture_loc = 0;

   gst_gl_context_clear_shader (filter->context);
   gl->BindTexture (GL_TEXTURE_2D, 0);

   gl->ClearColor (0.f, 0.f, 0.f, 0.f);
   gl->Clear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

   gst_gl_shader_use (transformation->shader);

   attr_position_loc =
       gst_gl_shader_get_attribute_location (transformation->shader, "position");

   attr_texture_loc =
       gst_gl_shader_get_attribute_location (transformation->shader, "uv");

   /* Load the vertex position */
   gl->VertexAttribPointer (attr_position_loc, 4, GL_FLOAT,
       GL_FALSE, 0, positions);

   /* Load the texture coordinate */
   gl->VertexAttribPointer (attr_texture_loc, 2, GL_FLOAT,
       GL_FALSE, 0, texture_coordinates);

   gl->EnableVertexAttribArray (attr_position_loc);
   gl->EnableVertexAttribArray (attr_texture_loc);

   gl->ActiveTexture (GL_TEXTURE0);
   gl->BindTexture (GL_TEXTURE_2D, transformation->in_tex);
   gst_gl_shader_set_uniform_1i (transformation->shader, "texture", 0);

   graphene_matrix_to_float (&transformation->mvp_matrix, temp_matrix);
   gst_gl_shader_set_uniform_matrix_4fv (transformation->shader, "mvp",
       1, GL_FALSE, temp_matrix);

   gl->DrawElements (GL_TRIANGLE_STRIP, 5, GL_UNSIGNED_SHORT, indices);

   gl->DisableVertexAttribArray (attr_position_loc);
   gl->DisableVertexAttribArray (attr_texture_loc);

   gst_gl_context_clear_shader (filter->context);
 }
	/*
	* GStreamer
	* Copyright (C) 2014 Lubosz Sarnecki <lubosz@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-gltransformation
	*
	* Transforms video on the GPU.
	*
	* <refsect2>
	* <title>Examples</title>
	* \|[
	* gst-launch gltestsrc ! gltransformation rotation-z=45 ! glimagesink
	* ]\| A pipeline to rotate by 45 degrees
	* \|[
	* gst-launch gltestsrc ! gltransformation translation-x=0.5 ! glimagesink
	* ]\| Translate the video by 0.5
	* \|[
	* gst-launch gltestsrc ! gltransformation scale-y=0.5 scale-x=0.5 ! glimagesink
	* ]\| Resize the video by 0.5
	* \|[
	* gst-launch gltestsrc ! gltransformation rotation-x=-45 ortho=True ! glimagesink
	* ]\| Rotate the video around the X-Axis by -45° with an orthographic projection
	* </refsect2>
	*/

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

	#include <gst/gl/gstglapi.h>
	#include "gstgltransformation.h"

	#define GST_CAT_DEFAULT gst_gl_transformation_debug
	GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);

	enum
	{
	PROP_0,
	PROP_FOVY,
	PROP_ORTHO,
	PROP_TRANSLATION_X,
	PROP_TRANSLATION_Y,
	PROP_TRANSLATION_Z,
	PROP_ROTATION_X,
	PROP_ROTATION_Y,
	PROP_ROTATION_Z,
	PROP_SCALE_X,
	PROP_SCALE_Y
	};

	#define DEBUG_INIT \
	GST_DEBUG_CATEGORY_INIT (gst_gl_transformation_debug, "gltransformation", 0, "gltransformation element");

	G_DEFINE_TYPE_WITH_CODE (GstGLTransformation, gst_gl_transformation,
	GST_TYPE_GL_FILTER, DEBUG_INIT);

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

	static gboolean gst_gl_transformation_set_caps (GstGLFilter * filter,
	GstCaps * incaps, GstCaps * outcaps);

	static void gst_gl_transformation_reset (GstGLFilter * filter);
	static gboolean gst_gl_transformation_init_shader (GstGLFilter * filter);
	static void gst_gl_transformation_callback (gpointer stuff);
	static void gst_gl_transformation_build_mvp (GstGLTransformation *
	transformation);

	static gboolean gst_gl_transformation_filter_texture (GstGLFilter * filter,
	guint in_tex, guint out_tex);

	/* vertex source */
	static const gchar *cube_v_src =
	"attribute vec4 position; \n"
	"attribute vec2 uv; \n"
	"uniform mat4 mvp; \n"
	"varying vec2 out_uv; \n"
	"void main() \n"
	"{ \n"
	" gl_Position = mvp * position; \n"
	" out_uv = uv; \n"
	"} \n";

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

	static void
	gst_gl_transformation_class_init (GstGLTransformationClass * klass)
	{
	GObjectClass *gobject_class;
	GstElementClass *element_class;

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

	gobject_class->set_property = gst_gl_transformation_set_property;
	gobject_class->get_property = gst_gl_transformation_get_property;

	GST_GL_FILTER_CLASS (klass)->onInitFBO = gst_gl_transformation_init_shader;
	GST_GL_FILTER_CLASS (klass)->onReset = gst_gl_transformation_reset;
	GST_GL_FILTER_CLASS (klass)->set_caps = gst_gl_transformation_set_caps;
	GST_GL_FILTER_CLASS (klass)->filter_texture =
	gst_gl_transformation_filter_texture;

	g_object_class_install_property (gobject_class, PROP_FOVY,
	g_param_spec_float ("fovy", "Fovy", "Field of view angle in degrees",
	0.0, G_MAXFLOAT, 90.0, G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_ORTHO,
	g_param_spec_boolean ("ortho", "Orthographic",
	"Use orthographic projection", FALSE,
	G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	/* Rotation */
	g_object_class_install_property (gobject_class, PROP_ROTATION_X,
	g_param_spec_float ("rotation-x", "X Rotation",
	"Rotates the video around the X-Axis in degrees.",
	-G_MAXFLOAT, G_MAXFLOAT, 0.0,
	G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_ROTATION_Y,
	g_param_spec_float ("rotation-y", "Y Rotation",
	"Rotates the video around the Y-Axis in degrees.",
	-G_MAXFLOAT, G_MAXFLOAT, 0.0,
	G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_ROTATION_Z,
	g_param_spec_float ("rotation-z", "Z Rotation",
	"Rotates the video around the Z-Axis in degrees.",
	-G_MAXFLOAT, G_MAXFLOAT, 0.0,
	G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	/* Translation */
	g_object_class_install_property (gobject_class, PROP_TRANSLATION_X,
	g_param_spec_float ("translation-x", "X Translation",
	"Translates the video at the X-Axis.",
	-G_MAXFLOAT, G_MAXFLOAT, 0.0,
	G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_TRANSLATION_Y,
	g_param_spec_float ("translation-y", "Y Translation",
	"Translates the video at the Y-Axis.",
	-G_MAXFLOAT, G_MAXFLOAT, 0.0,
	G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_TRANSLATION_Z,
	g_param_spec_float ("translation-z", "Z Translation",
	"Translates the video at the Z-Axis.",
	-G_MAXFLOAT, G_MAXFLOAT, 0.0,
	G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	/* Scale */
	g_object_class_install_property (gobject_class, PROP_SCALE_X,
	g_param_spec_float ("scale-x", "X Scale",
	"Scale multiplierer for the X-Axis.",
	0.0, G_MAXFLOAT, 1.0, G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	g_object_class_install_property (gobject_class, PROP_SCALE_Y,
	g_param_spec_float ("scale-y", "Y Scale",
	"Scale multiplierer for the Y-Axis.",
	0.0, G_MAXFLOAT, 1.0, G_PARAM_READWRITE \| G_PARAM_STATIC_STRINGS));

	gst_element_class_set_metadata (element_class, "OpenGL transformation filter",
	"Filter/Effect/Video", "Transform video on the GPU",
	"Lubosz Sarnecki <lubosz@gmail.com>");
	}

	static void
	gst_gl_transformation_init (GstGLTransformation * filter)
	{
	filter->shader = NULL;
	filter->fovy = 90;
	filter->aspect = 0;
	filter->znear = 0.1;
	filter->zfar = 100;

	filter->xscale = 1.0;
	filter->yscale = 1.0;

	filter->in_tex = 0;

	gst_gl_transformation_build_mvp (filter);
	}

	static void
	gst_gl_transformation_build_mvp (GstGLTransformation * transformation)
	{
	graphene_point3d_t translation_vector =
	GRAPHENE_POINT3D_INIT (transformation->xtranslation,
	transformation->ytranslation,
	transformation->ztranslation);

	graphene_matrix_t model_matrix;
	graphene_matrix_t projection_matrix;
	graphene_matrix_t view_matrix;
	graphene_matrix_t vp_matrix;

	graphene_vec3_t eye;
	graphene_vec3_t center;
	graphene_vec3_t up;

	graphene_vec3_init (&eye, 0.f, 0.f, 1.f);
	graphene_vec3_init (&center, 0.f, 0.f, 0.f);
	graphene_vec3_init (&up, 0.f, 1.f, 0.f);

	graphene_matrix_init_rotate (&model_matrix,
	transformation->xrotation, graphene_vec3_x_axis ());
	graphene_matrix_rotate (&model_matrix,
	transformation->yrotation, graphene_vec3_y_axis ());
	graphene_matrix_rotate (&model_matrix,
	transformation->zrotation, graphene_vec3_z_axis ());
	graphene_matrix_scale (&model_matrix,
	transformation->xscale, transformation->yscale, 1.0f);
	graphene_matrix_translate (&model_matrix, &translation_vector);

	if (transformation->ortho) {
	graphene_matrix_init_ortho (&projection_matrix,
	-transformation->aspect, transformation->aspect,
	-1, 1, transformation->znear, transformation->zfar);
	} else {
	graphene_matrix_init_perspective (&projection_matrix,
	transformation->fovy,
	transformation->aspect, transformation->znear, transformation->zfar);
	}

	graphene_matrix_init_look_at (&view_matrix, &eye, &center, &up);

	graphene_matrix_multiply (&view_matrix, &projection_matrix, &vp_matrix);
	graphene_matrix_multiply (&model_matrix, &vp_matrix,
	&transformation->mvp_matrix);
	}

	static void
	gst_gl_transformation_set_property (GObject * object, guint prop_id,
	const GValue * value, GParamSpec * pspec)
	{
	GstGLTransformation *filter = GST_GL_TRANSFORMATION (object);

	switch (prop_id) {
	case PROP_FOVY:
	filter->fovy = g_value_get_float (value);
	break;
	case PROP_ORTHO:
	filter->ortho = g_value_get_boolean (value);
	break;
	case PROP_TRANSLATION_X:
	filter->xtranslation = g_value_get_float (value);
	break;
	case PROP_TRANSLATION_Y:
	filter->ytranslation = g_value_get_float (value);
	break;
	case PROP_TRANSLATION_Z:
	filter->ztranslation = g_value_get_float (value);
	break;
	case PROP_ROTATION_X:
	filter->xrotation = g_value_get_float (value);
	break;
	case PROP_ROTATION_Y:
	filter->yrotation = g_value_get_float (value);
	break;
	case PROP_ROTATION_Z:
	filter->zrotation = g_value_get_float (value);
	break;
	case PROP_SCALE_X:
	filter->xscale = g_value_get_float (value);
	break;
	case PROP_SCALE_Y:
	filter->yscale = g_value_get_float (value);
	break;
	default:
	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
	break;
	}
	gst_gl_transformation_build_mvp (filter);
	}

	static void
	gst_gl_transformation_get_property (GObject * object, guint prop_id,
	GValue * value, GParamSpec * pspec)
	{
	GstGLTransformation *filter = GST_GL_TRANSFORMATION (object);

	switch (prop_id) {
	case PROP_FOVY:
	g_value_set_float (value, filter->fovy);
	break;
	case PROP_ORTHO:
	g_value_set_boolean (value, filter->ortho);
	break;
	case PROP_TRANSLATION_X:
	g_value_set_float (value, filter->xtranslation);
	break;
	case PROP_TRANSLATION_Y:
	g_value_set_float (value, filter->ytranslation);
	break;
	case PROP_TRANSLATION_Z:
	g_value_set_float (value, filter->ztranslation);
	break;
	case PROP_ROTATION_X:
	g_value_set_float (value, filter->xrotation);
	break;
	case PROP_ROTATION_Y:
	g_value_set_float (value, filter->yrotation);
	break;
	case PROP_ROTATION_Z:
	g_value_set_float (value, filter->zrotation);
	break;
	case PROP_SCALE_X:
	g_value_set_float (value, filter->xscale);
	break;
	case PROP_SCALE_Y:
	g_value_set_float (value, filter->yscale);
	break;
	default:
	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
	break;
	}
	}

	static gboolean
	gst_gl_transformation_set_caps (GstGLFilter * filter, GstCaps * incaps,
	GstCaps * outcaps)
	{
	GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);

	transformation->aspect =
	(gdouble) GST_VIDEO_INFO_WIDTH (&filter->out_info) /
	(gdouble) GST_VIDEO_INFO_HEIGHT (&filter->out_info);

	gst_gl_transformation_build_mvp (transformation);

	return TRUE;
	}

	static void
	gst_gl_transformation_reset (GstGLFilter * filter)
	{
	GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);

	/* blocking call, wait until the opengl thread has destroyed the shader */
	if (transformation->shader)
	gst_gl_context_del_shader (filter->context, transformation->shader);
	transformation->shader = NULL;
	}

	static gboolean
	gst_gl_transformation_init_shader (GstGLFilter * filter)
	{
	GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);

	if (gst_gl_context_get_gl_api (filter->context)) {
	/* blocking call, wait until the opengl thread has compiled the shader */
	return gst_gl_context_gen_shader (filter->context, cube_v_src, cube_f_src,
	&transformation->shader);
	}
	return TRUE;
	}

	static gboolean
	gst_gl_transformation_filter_texture (GstGLFilter * filter, guint in_tex,
	guint out_tex)
	{
	GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);

	transformation->in_tex = in_tex;

	/* blocking call, use a FBO */
	gst_gl_context_use_fbo_v2 (filter->context,
	GST_VIDEO_INFO_WIDTH (&filter->out_info),
	GST_VIDEO_INFO_HEIGHT (&filter->out_info),
	filter->fbo, filter->depthbuffer,
	out_tex, gst_gl_transformation_callback, (gpointer) transformation);

	return TRUE;
	}

	static void
	gst_gl_transformation_callback (gpointer stuff)
	{
	GstGLFilter *filter = GST_GL_FILTER (stuff);
	GstGLTransformation *transformation = GST_GL_TRANSFORMATION (filter);
	GstGLFuncs *gl = filter->context->gl_vtable;

	/* INDENT-OFF */

	const GLfloat positions[] = {
	-transformation->aspect, 1.0, 0.0, 1.0,
	transformation->aspect, 1.0, 0.0, 1.0,
	transformation->aspect, -1.0, 0.0, 1.0,
	-transformation->aspect, -1.0, 0.0, 1.0,
	};

	const GLfloat texture_coordinates[] = {
	0.0, 1.0,
	1.0, 1.0,
	1.0, 0.0,
	0.0, 0.0,
	};

	/* INDENT-ON */

	GLushort indices[] = { 0, 1, 2, 3, 0 };

	GLfloat temp_matrix[16];

	GLint attr_position_loc = 0;
	GLint attr_texture_loc = 0;

	gst_gl_context_clear_shader (filter->context);
	gl->BindTexture (GL_TEXTURE_2D, 0);

	gl->ClearColor (0.f, 0.f, 0.f, 0.f);
	gl->Clear (GL_COLOR_BUFFER_BIT \| GL_DEPTH_BUFFER_BIT);

	gst_gl_shader_use (transformation->shader);

	attr_position_loc =
	gst_gl_shader_get_attribute_location (transformation->shader, "position");

	attr_texture_loc =
	gst_gl_shader_get_attribute_location (transformation->shader, "uv");

	/* Load the vertex position */
	gl->VertexAttribPointer (attr_position_loc, 4, GL_FLOAT,
	GL_FALSE, 0, positions);

	/* Load the texture coordinate */
	gl->VertexAttribPointer (attr_texture_loc, 2, GL_FLOAT,
	GL_FALSE, 0, texture_coordinates);

	gl->EnableVertexAttribArray (attr_position_loc);
	gl->EnableVertexAttribArray (attr_texture_loc);

	gl->ActiveTexture (GL_TEXTURE0);
	gl->BindTexture (GL_TEXTURE_2D, transformation->in_tex);
	gst_gl_shader_set_uniform_1i (transformation->shader, "texture", 0);

	graphene_matrix_to_float (&transformation->mvp_matrix, temp_matrix);
	gst_gl_shader_set_uniform_matrix_4fv (transformation->shader, "mvp",
	1, GL_FALSE, temp_matrix);

	gl->DrawElements (GL_TRIANGLE_STRIP, 5, GL_UNSIGNED_SHORT, indices);

	gl->DisableVertexAttribArray (attr_position_loc);
	gl->DisableVertexAttribArray (attr_texture_loc);

	gst_gl_context_clear_shader (filter->context);
	}