scufpong/src/game/SinglePlayer.c

#include "cglm/vec4.h"
#include "scufeng/Scene.h"

#include "SinglePlayer.h"
#include "screen.h"

SinglePlayer SinglePlayer_alloc(
    unsigned int screen_w,
    unsigned int screen_h,
    float paddles_w,
    float paddles_h,
    float paddle_l_x,
    float paddle_speed,
    float ball_w,
    vec2 ball_pos,
    float ball_speed
) {
    SinglePlayer sp = {
        .screen_w = screen_w,
        .screen_h = screen_h,
        .state = GameState_new(
            paddles_w,
            paddles_h,
            paddle_l_x,
            paddle_speed,
            ball_w,
            ball_pos,
            ball_speed
        ),
        .paddle_l = SEMesh_rect_color_alloc(GLM_VEC4_ONE),
        .paddle_r = SEMesh_rect_color_alloc(GLM_VEC4_ONE),
        .ball = SEMesh_rect_color_alloc(GLM_VEC4_ONE),
    };
    sp.paddle_l.transform.scale[0] = screen_w * paddles_w;
    sp.paddle_l.transform.scale[1] = screen_h * paddles_h;
    sp.paddle_l.transform.pos[0] = screen_w * paddle_l_x;
    sp.paddle_l.transform.pos[1] = screen_h / 2.0f;

    sp.paddle_r.transform.scale[0] = screen_w * paddles_w;
    sp.paddle_r.transform.scale[1] = screen_h * paddles_h;
    sp.paddle_r.transform.pos[0] = screen_w * (1.0f - paddle_l_x);
    sp.paddle_r.transform.pos[1] = screen_h / 2.0f;

    sp.ball.transform.scale[0] = screen_w * ball_w;
    sp.ball.transform.scale[1] = sp.ball.transform.scale[0];
    sp.ball.transform.pos[0] = screen_w * ball_pos[0];
    sp.ball.transform.pos[1] = screen_h * ball_pos[1];

    return sp;
}

void SinglePlayer_free(SinglePlayer *sp) {
    SEMesh_free(&sp->paddle_l);
    SEMesh_free(&sp->paddle_r);
    SEMesh_free(&sp->ball);
}

static void pos_convert(
    vec3 render_pos,
    const vec3 state_pos,
    const unsigned int screen_w,
    const unsigned int screen_h
) {
    render_pos[0] = state_pos[0] * screen_w;
    render_pos[1] = (1.0f - state_pos[1]) * screen_h;
}

static void update_shapes(
    const GameState *const state,
    SEMesh *const paddle_l,
    SEMesh *const paddle_r,
    SEMesh *const ball,
    const unsigned int screen_w,
    const unsigned int screen_h
) {

    // Paddles
    pos_convert(paddle_l->transform.pos, state->paddle_l.pos, screen_w, screen_h);
    pos_convert(paddle_r->transform.pos, state->paddle_r.pos, screen_w, screen_h);

    // Ball
    pos_convert(ball->transform.pos, state->ball.pos, screen_w, screen_h);
}

static bool key_input_handle(GameState *const state) {
    if (se_get_key(SE_KEY_W) == SE_KEY_ACTION_PRESS) {
        GameState_move_paddle_l(state, SE_UP);
    } else if (se_get_key(SE_KEY_S) == SE_KEY_ACTION_PRESS) {
        GameState_move_paddle_l(state, SE_DOWN);
    } else {
        GameState_move_paddle_l(state, SE_NONE);
    }

    if (se_get_key(SE_KEY_ESCAPE) == SE_KEY_ACTION_PRESS) {
        return true;
    }

    return false;
}

Screen SinglePlayer_tick(SinglePlayer *const sp, const double delta) {
    if (key_input_handle(&sp->state)) {
        return PONG_MAIN_MENU;
    }
    GameState_update(&sp->state, delta);
    update_shapes(
        &sp->state,
        &sp->paddle_l,
        &sp->paddle_r,
        &sp->ball,
        sp->screen_w,
        sp->screen_h
    );
    SEMesh *meshes[] = {
        &sp->paddle_l,
        &sp->paddle_r,
        &sp->ball
    };
    se_render_meshes_2d(meshes, sizeof(meshes) / sizeof(meshes[0]));

    return PONG_SINGLEPLAYER;
}