RogueLife/src/enemies.c

#include "enemies.h"

#include <stdlib.h>

static enemy_t const slime = {
    .name = "Slime",
    .hitbox = (frect_t){ -fix(3)/16, fix(4)/16, -fix(2)/16, fix(3)/16 },
    .sprite = (frect_t){ -fix(5)/16, fix(5)/16, -fix(4)/16, fix(3)/16 },
    .anim_idle = { anim_slime_idle_left, anim_slime_idle_right },
    .anim_death = { anim_slime_death_left, anim_slime_death_right },
    .anim_damage = { anim_slime_damage_left, anim_slime_damage_right },
    .movement_params = {
        .max_speed = fix(1),
        .propulsion = fix(12),
    },
    .HP = {
        .base = fix(10),
        .growth = fix(5),
        .affinity = fix(3),
    },
    .ATK = {
        .base = fix(5),
        .growth = fix(2),
        .affinity = fix(1),
    },
    .DEF = {
        .base = fix(2),
        .growth = fix(1),
        .affinity = fix(0.5),
    },
};

static enemy_t const bat = {
    .name = "Bat",
    .hitbox = (frect_t){ -fix(3)/16, fix(4)/16, -fix(2)/16, fix(3)/16 },
    .sprite = (frect_t){ -fix(5)/16, fix(5)/16, -fix(4)/16, fix(3)/16 },
    .anim_idle = { anim_bat_idle_left, anim_bat_idle_right },
    .anim_death = { anim_bat_death_left, anim_bat_death_right },
    .anim_damage = { anim_bat_damage_left, anim_bat_damage_right },
    .movement_params = {
        .max_speed = fix(1.8),
        .propulsion = fix(8),
    },
    .HP = {
        .base = fix(8),
        .growth = fix(4),
        .affinity = fix(2),
    },
    .ATK = {
        .base = fix(8),
        .growth = fix(2),
        .affinity = fix(2),
    },
    .DEF = {
        .base = fix(2),
        .growth = fix(2),
        .affinity = fix(1),
    },
};

enemy_t const * const enemies[] = {
    [ENEMY_SLIME] = &slime,
    [ENEMY_BAT] = &bat,
};

int instantiate_stat(enemy_stat_t const *stat, int level)
{
    fixed_t value = stat->base + stat->growth * (level - 1) +
        stat->affinity * (level * (level - 1) / 2);

    fixed_t variation = value / 8;
    value = (value - variation) + (rand() % (2 * variation));

    return ffloor(value);
}

entity_t *enemy_spawn(int enemy_id, int level)
{
    if(enemy_id < 0 || (size_t)enemy_id >= sizeof enemies / sizeof *enemies)
        return NULL;

    entity_t *e = malloc(sizeof *e);
    if(!e) return NULL;

    enemy_t const *data = enemies[enemy_id];

    /* These will probably be overridden by the caller */
    e->movement.x = 0;
    e->movement.y = 0;
    e->movement.vx = 0;
    e->movement.vy = 0;
    e->movement.facing = LEFT;
    e->movement.dash = 0;
    e->movement.dash_facing = LEFT;

    e->movement_params = &data->movement_params;
    e->anim_priority = 0;
    entity_set_anim(e, data->anim_idle[0], 1);

    e->hitbox = data->hitbox;
    e->sprite = data->sprite;

    e->current_attack = NULL;
    e->attack_follows_movement = false;

    e->identity = enemy_id;

    e->HP_max = instantiate_stat(&data->HP, level);
    e->ATK    = instantiate_stat(&data->ATK, level);
    e->DEF    = instantiate_stat(&data->DEF, level);

    e->HP = e->HP_max;

    return e;
}