/**
 * Example illustrating usage of fog effect.
 *
 * @verbatim
 * gcc -o evas-3d-fog evas-3d-fog.c `pkg-config --libs --cflags efl evas ecore ecore-evas eo`-lm
 * @endverbatim
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#else
#define EFL_BETA_API_SUPPORT
#define EFL_EO_API_SUPPORT
#endif

#include <math.h>
#include <Eo.h>
#include <Evas.h>
#include <Ecore.h>
#include <Ecore_Evas.h>

#define  WIDTH          1024
#define  HEIGHT         1024
#define  FOG_COLOR      0.5, 0.5, 0.5
#define  FOG_FACTOR     0.2

typedef struct _Scene_Data
{
   Eo     *scene;
   Eo     *root_node;
   Eo     *camera_node;
   Eo     *light_node;
   Eo     *mesh_node;
   Eo     *mesh_node1;
   Eo     *animation_node;
   Eo     *sphere;

   Eo     *camera;
   Eo     *light;
   Eo     *mesh;
   Eo     *mesh1;
   Eo     *material;
} Scene_Data;

Ecore_Evas       *ecore_evas  = NULL;
Evas             *evas        = NULL;
Eo               *background  = NULL;
Eo               *image       = NULL;

static void
_on_delete(Ecore_Evas *ee EINA_UNUSED)
{
   ecore_main_loop_quit();
}

static void
_on_canvas_resize(Ecore_Evas *ee)
{
   int w, h;

   ecore_evas_geometry_get(ee, NULL, NULL, &w, &h);

   evas_object_resize(background, w, h);
   efl_gfx_size_set(background, w, h);
   efl_gfx_size_set(image, w, h);
}

static Eina_Bool
_animate_scene(void *data)
{
   static float angle = 0.0f;
   Scene_Data *scene = (Scene_Data *)data;

   angle += 0.5;

   evas_canvas3d_node_orientation_angle_axis_set(scene->animation_node, angle, 0.0, 1.0, 0.0);

   if (angle > 360.0) angle -= 360.0f;

   return EINA_TRUE;
}

static void
_camera_setup(Scene_Data *data)
{
   data->camera = eo_add(EVAS_CANVAS3D_CAMERA_CLASS, evas);

   evas_canvas3d_camera_projection_perspective_set(data->camera, 60.0, 1.0, 2.0, 50.0);

  data->camera_node =
      eo_add(EVAS_CANVAS3D_NODE_CLASS, evas, evas_canvas3d_node_constructor(eo_self, EVAS_CANVAS3D_NODE_TYPE_CAMERA));

  evas_canvas3d_node_camera_set(data->camera_node, data->camera);
  evas_canvas3d_node_position_set(data->camera_node, 0.0, 0.0, 7.0);
  evas_canvas3d_node_look_at_set(data->camera_node, EVAS_CANVAS3D_SPACE_PARENT, 0.0, 0.0, 0.0, EVAS_CANVAS3D_SPACE_PARENT, 0.0, 1.0, 0.0);

  evas_canvas3d_node_member_add(data->root_node, data->camera_node);
}

static void
_light_setup(Scene_Data *data)
{
   data->light = eo_add(EVAS_CANVAS3D_LIGHT_CLASS, evas);
   evas_canvas3d_light_ambient_set(data->light, 0.2, 0.2, 0.2, 1.0);
   evas_canvas3d_light_diffuse_set(data->light, 1.0, 1.0, 1.0, 1.0);
   evas_canvas3d_light_specular_set(data->light, 1.0, 1.0, 1.0, 1.0);

   data->light_node =
      eo_add(EVAS_CANVAS3D_NODE_CLASS, evas, evas_canvas3d_node_constructor(eo_self, EVAS_CANVAS3D_NODE_TYPE_LIGHT));
   evas_canvas3d_node_light_set(data->light_node, data->light);
   evas_canvas3d_node_position_set(data->light_node, 0.0, 0.0, 10.0);
   evas_canvas3d_node_look_at_set(data->light_node, EVAS_CANVAS3D_SPACE_PARENT, 0.0, 0.0, 0.0, EVAS_CANVAS3D_SPACE_PARENT, 0.0, 1.0, 0.0);
   evas_canvas3d_node_member_add(data->root_node, data->light_node);
}

static void
_set_ball(Eo *mesh, Eo *sphere, Evas_Canvas3D_Material *material)
{
   evas_canvas3d_mesh_from_primitive_set(mesh, 0, sphere);
   evas_canvas3d_mesh_shader_mode_set(mesh, EVAS_CANVAS3D_SHADER_MODE_PHONG);
   evas_canvas3d_mesh_frame_material_set(mesh, 0, material);
}


static void
_mesh_setup(Scene_Data *data)
{
   data->material = eo_add(EVAS_CANVAS3D_MATERIAL_CLASS, evas);

   evas_canvas3d_material_enable_set(data->material, EVAS_CANVAS3D_MATERIAL_ATTRIB_AMBIENT, EINA_TRUE);
   evas_canvas3d_material_enable_set(data->material, EVAS_CANVAS3D_MATERIAL_ATTRIB_DIFFUSE, EINA_TRUE);
   evas_canvas3d_material_enable_set(data->material, EVAS_CANVAS3D_MATERIAL_ATTRIB_SPECULAR, EINA_TRUE);
   evas_canvas3d_material_color_set(data->material, EVAS_CANVAS3D_MATERIAL_ATTRIB_AMBIENT, 0.2, 0.2, 0.2, 1.0);
   evas_canvas3d_material_color_set(data->material, EVAS_CANVAS3D_MATERIAL_ATTRIB_DIFFUSE, 0.8, 0.8, 0.8, 1.0);
   evas_canvas3d_material_color_set(data->material, EVAS_CANVAS3D_MATERIAL_ATTRIB_SPECULAR, 1.0, 1.0, 1.0, 1.0);
   evas_canvas3d_material_shininess_set(data->material, 100.0);

   data->sphere = eo_add(EVAS_CANVAS3D_PRIMITIVE_CLASS, evas);
   evas_canvas3d_primitive_form_set(data->sphere, EVAS_CANVAS3D_MESH_PRIMITIVE_SPHERE);
   evas_canvas3d_primitive_precision_set(data->sphere, 50);

   data->mesh = eo_add(EVAS_CANVAS3D_MESH_CLASS, evas);
   data->mesh1 = eo_add(EVAS_CANVAS3D_MESH_CLASS, evas);

   _set_ball(data->mesh, data->sphere, data->material);
   _set_ball(data->mesh1, data->sphere, data->material);

   data->animation_node =
      eo_add(EVAS_CANVAS3D_NODE_CLASS, evas, evas_canvas3d_node_constructor(eo_self, EVAS_CANVAS3D_NODE_TYPE_NODE));

   data->mesh_node =
      eo_add(EVAS_CANVAS3D_NODE_CLASS, evas, evas_canvas3d_node_constructor(eo_self, EVAS_CANVAS3D_NODE_TYPE_MESH));

   evas_canvas3d_node_member_add(data->animation_node, data->mesh_node);
   evas_canvas3d_node_member_add(data->root_node, data->animation_node);
   evas_canvas3d_node_mesh_add(data->mesh_node, data->mesh);
   evas_canvas3d_node_position_set(data->mesh_node, 0.0, 0.0, 3.0);

   data->mesh_node1 =
      eo_add(EVAS_CANVAS3D_NODE_CLASS, evas, evas_canvas3d_node_constructor(eo_self, EVAS_CANVAS3D_NODE_TYPE_MESH));

   evas_canvas3d_node_member_add(data->root_node, data->mesh_node1);
   evas_canvas3d_node_mesh_add(data->mesh_node1, data->mesh1);
   evas_canvas3d_node_scale_set(data->mesh_node1, 3, 3, 3);

   evas_canvas3d_mesh_fog_enable_set(data->mesh, EINA_TRUE);
   evas_canvas3d_mesh_fog_color_set(data->mesh, FOG_COLOR, FOG_FACTOR);
   evas_canvas3d_mesh_fog_enable_set(data->mesh1, EINA_TRUE);
   evas_canvas3d_mesh_fog_color_set(data->mesh1, FOG_COLOR, FOG_FACTOR);
}

static void
_scene_setup(Scene_Data *data)
{
   data->scene = eo_add(EVAS_CANVAS3D_SCENE_CLASS, evas);

   evas_canvas3d_scene_size_set(data->scene, WIDTH, HEIGHT);
   evas_canvas3d_scene_background_color_set(data->scene, FOG_COLOR, 1);

   data->root_node =
      eo_add(EVAS_CANVAS3D_NODE_CLASS, evas, evas_canvas3d_node_constructor(eo_self, EVAS_CANVAS3D_NODE_TYPE_NODE));

   _camera_setup(data);
   _light_setup(data);
   _mesh_setup(data);

   evas_canvas3d_scene_root_node_set(data->scene, data->root_node);
   evas_canvas3d_scene_camera_node_set(data->scene, data->camera_node);
}

int
main(void)
{
   //Unless Evas 3D supports Software renderer, we set gl backened forcely.
   setenv("ECORE_EVAS_ENGINE", "opengl_x11", 1);
   Scene_Data data;
   Ecore_Animator *anim;

   if (!ecore_evas_init()) return 0;

   ecore_evas = ecore_evas_new("opengl_x11", 10, 10, WIDTH, HEIGHT, NULL);

   if (!ecore_evas) return 0;

   ecore_evas_callback_delete_request_set(ecore_evas, _on_delete);
   ecore_evas_callback_resize_set(ecore_evas, _on_canvas_resize);
   ecore_evas_show(ecore_evas);

   evas = ecore_evas_get(ecore_evas);

   _scene_setup(&data);

   /* Add a background rectangle objects. */
   background = eo_add(EFL_CANVAS_RECTANGLE_CLASS, evas);
   efl_gfx_color_set(background, 0, 0, 0, 255);
   efl_gfx_size_set(background, WIDTH, HEIGHT);
   efl_gfx_visible_set(background, EINA_TRUE);

   /* Add an image object for 3D scene rendering. */
   image = eo_add(EFL_CANVAS_SCENE3D_CLASS, evas);

   efl_gfx_size_set(image, WIDTH, HEIGHT);
   efl_gfx_visible_set(image, EINA_TRUE);

   /* Set the image object as render target for 3D scene. */
   efl_canvas_scene3d_set(image, data.scene);

   /* Add animation timer callback. */
   ecore_animator_frametime_set(0.008);
   anim = ecore_animator_add(_animate_scene, &data);

   /* Enter main loop. */
   ecore_main_loop_begin();

   ecore_evas_free(ecore_evas);
   ecore_evas_shutdown();
   ecore_animator_del(anim);

   return 0;
}