island-ctory/src/player.c

#include "player.h"

#include <string.h>

#include "actor.h"
#include "game.h"
#include "sdk/assets.h"
#include "sdk/joypad.h"

#define PLAYER_SPEED 2
#define GRAVITY 0x002e              //!< 0.18
#define PLAYER_INIT_JUMP_VY 0x0399  //!< 3.6
#define PLAYER_INIT_FALL_VY 0xff1a  //!< -1.1015625
#define MAX_VY 0xf900               //!< -7.0

#define SWITCH_ANIM_STATE(state)         \
    do {                                 \
        PLAYER_ACTOR->anim = (state);    \
        PLAYER_ACTOR->frame_counter = 0; \
        PLAYER_ACTOR->frame_idx = 0;     \
    } while (0)

player_t PLAYER;

ASSET(player_tiles, "player.2bpp");
ASSET(player_map, "player.map");

void player_init(void) {
    PLAYER.state = PLAYER_STATE_STAND;
    memcpy(VRAM_TILE_PTR(TILE_INDEX_PLAYER), &player_tiles[0],
           player_tiles_end - player_tiles);
}

void player_update(void) {
    if ((joypad_pressed & PAD_UP) && PLAYER.state != PLAYER_STATE_JUMP) {
        SWITCH_ANIM_STATE(ANIM_JUMP);
        PLAYER.state = PLAYER_STATE_JUMP;
        PLAYER.vy = PLAYER_INIT_JUMP_VY;
    }

    if (PLAYER.state == PLAYER_STATE_JUMP) {
        PLAYER.vy -= GRAVITY;
        *((uint16_t*)&PLAYER.y_lo) -= PLAYER.vy;

        if (player_bg_collides()) {
            if (PLAYER.vy & (1 << 15)) {
                PLAYER.y_hi--;
                while (player_bg_collides()) {
                    PLAYER.y_hi--;
                }
                SWITCH_ANIM_STATE(ANIM_STAND);
                PLAYER.state = PLAYER_STATE_STAND;
            } else {
                PLAYER.y_hi++;
                while (player_bg_collides()) {
                    PLAYER.y_hi++;
                }
            }
            PLAYER.vy = 0;
        }
    }

    if ((joypad_state & PAD_RIGHT) && PLAYER.x + TILE_WIDTH * 2 < SCRN_X) {
        PLAYER.dir = DIR_RIGHT;
        PLAYER.x += PLAYER_SPEED;
        if (player_bg_collides()) {
            PLAYER.x -= PLAYER_SPEED;
        }
    } else if ((joypad_state & PAD_LEFT) && PLAYER.x > 0) {
        PLAYER.dir = DIR_LEFT;
        PLAYER.x -= PLAYER_SPEED;
        if (player_bg_collides()) {
            PLAYER.x += PLAYER_SPEED;
        }
    }

    if (player_in_air() && PLAYER.state != PLAYER_STATE_JUMP) {
        PLAYER.state = PLAYER_STATE_JUMP;
        PLAYER.vy = PLAYER_INIT_FALL_VY;
    }

    PLAYER_ACTOR->flip = PLAYER.dir == DIR_LEFT;
    PLAYER_ACTOR->x = PLAYER.x;
    PLAYER_ACTOR->y = PLAYER.y_hi;
}