//---
// visible: Component for visible entities with a sprite
//
// Visible entities (which must also be physical in order to have a position)
// mostly consist of 2D sprites that either lie flat on the ground or stand
// vertically. They also have a visual elevation (z) which only affects the
// display, and can drop shadows.
//
// Below is a schematic diagram of visible objects' geometry.
//
//            |-_
//            |  `-_                z
//            |     `.              |     y
//       ^--- :-_    | < Wall       |_.-`
//     z |    :  `-_ |   sprite      `-_
//       |    :     `:                   x
//       v--- :_.-``-:
//        _.-``-_    :`-_
//        `-_    `x_ :_.-` < Floor sprite
//           `-_ _.-``
//              `
//
// The "x" marks the entity's anchor, which is the point of the object tied to
// its position (which is used for depth ordering among other things). The
// anchor is aligned with the sprite's anchor, before optionally adding a z
// displacement for elevated visible entities.
//---

#pragma once

#include "comp/entity.h"
#include "geometry.h"
#include "anim.h"

typedef struct
{
    /* Display elevation; has no influence on mechanics */
    fixed_t z;
    /* Current sprite */
    anim_state_t anim;
    /* Priority of current sprite (used to avoid animation conflicts) */
    uint8_t anim_priority;
    /* Sprite plane (either VERTICAL or HORIZONTAL) */
    uint8_t sprite_plane;
    /* Size of shadow cast (0 for no shadow; not all values are valid) */
    uint8_t shadow_size;

} visible_t;

/* Set the entity's animation. If the priority is strictly lower than the
   current animation's priority, this operation is ignored. */
void visible_set_anim(entity_t *e, anim_t const *anim, int priority);

/* Regular update function */
void visible_update(entity_t *e, fixed_t dt);