/* *****************************************************************************
 * libwindmill.h -- 3D rendering engine.
 * Copyright (C) 2017 Olivier "Ninestars" Lanneau
 * Copyright (C) 2017 Thomas "Cakeisalie5" Touhey <thomas@touhey.fr>
 *
 * This file is part of libwindmill.
 * libwindmill is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 3.0 of the License,
 * or (at your option) any later version.
 *
 * libwindmill 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with libwindmill; if not, see <http://www.gnu.org/licenses/>.
 * ************************************************************************** */
#ifndef LIBWINDMILL_H
# define LIBWINDMILL_H
# include <stdlib.h>
# include <string.h>
# include <math.h>
# define N  0
# define X  1
# define Y  2
# define Z  3
# define XC 4
# define YC 5
# define ZC 6

/* ************************************************************************** */
/*  Types                                                                     */
/* ************************************************************************** */
/* a vertex */
typedef struct Vertex {
	int x, y, z;
	char tx, ty;
	int z_normalized;
} wml_vertex_t;

/* a texture */
typedef struct Texture {
	const unsigned char *sprite;
	char width, height, offset;
} wml_texture_t;

/* a triangle */
typedef struct Triangle {
	/* coordinates */
	short x0, y0, z0;
	short x1, y1, z1;
	short x2, y2, z2;

	/* textures */
	struct Texture *texture_front;
	struct Texture *texture_back;
} wml_triangle_t;

/* a rectangle */
typedef struct Rectangle {
	/* coordinates */
	short x0, y0, z0;
	short x1, y1, z1;
	short x2, y2, z2;

	/* textures */
	struct Texture *texture_front;
	struct Texture *texture_back;
} wml_rectangle_t;

/* an object */
typedef struct Object {
	/* coordinates */
	int x, y, z;
	char axe; float angle;

	/* rectangles */
	wml_rectangle_t *list_rect;
	int list_rect_size;

	/* triangles */
	wml_triangle_t *list_tri;
	int list_tri_size;
} wml_object_t;

/* a map */
typedef struct Map {
	int id;

	/* objects */
	struct Object **list_object;
	int list_object_size;
} wml_map_t;

/* a scene */
typedef struct Scene {
	/* flow control */
	int stop_execution;

	/* camera */
	float camera_x, camera_y, camera_z;
	float camera_yaw, camera_pitch;
	int scale_coef, near, far;
	float near_coef;
	int far_coef;
	float div_coef;
	int viewport_x1, viewport_y1, viewport_x2, viewport_y2;
	int shift_x, shift_y;
	unsigned short *z_buffer;
	int z_buffer_size, z_buffer_offset, z_buffer_width;

	/* texture, map, background */
	struct Texture *hidden, *black, *white;
	struct Map map;
	const unsigned char *background;

	/* i don't know what this is, yet */
	int a1, a2, a3, a4, a5, a6, a7, a8, a9;
} wml_scene_t;

/* ************************************************************************** */
/*  Functions                                                                 */
/* ************************************************************************** */
/* update things */
void wml_update_camera(wml_scene_t *scene);
void wml_update_viewport(wml_scene_t *scene);

/* render */
void wml_render_draw(wml_scene_t *scene);

void wml_dynamic(wml_vertex_t *vertex,
	int axe, int x, int y, int z,
	float cosinus, float sinus);
void wml_transform(wml_scene_t *scene, wml_vertex_t *vertex);

void wml_render_triangle(wml_scene_t *scene,
	wml_vertex_t *vertex1, wml_vertex_t *vertex2, wml_vertex_t *vertex3,
	wml_texture_t *texture);
void wml_render_triangle_black(wml_scene_t *scene,
	wml_vertex_t *vertex1, wml_vertex_t *vertex2, wml_vertex_t *vertex3,
	wml_texture_t *texture);
void wml_render_triangle_white(wml_scene_t *scene,
	wml_vertex_t *vertex1, wml_vertex_t *vertex2, wml_vertex_t *vertex3,
	wml_texture_t *texture);

void wml_edge(wml_vertex_t *a, wml_vertex_t *b, wml_vertex_t *c);
void wml_edge_start(wml_vertex_t *a, wml_vertex_t *b, int px, int py);
void wml_edge_step_x(wml_vertex_t *a, wml_vertex_t *b);
void wml_edge_step_y(wml_vertex_t *a, wml_vertex_t *b);

void wml_move_camera_face(wml_scene_t *scene, float value);
void wml_move_camera_side(wml_scene_t *scene, float value);

#endif /* LIBWINDMILL_H */