/*
* Copyright (c) 2017 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr.h>
#include <sys/printk.h>
#include <board.h>
#include <drivers/gpio.h>
#include <device.h>
#include <string.h>
#include <drivers/pwm.h>
#include <debug/stack.h>
#include <display/mb_display.h>
#include <bluetooth/bluetooth.h>
#include "pong.h"
/* The micro:bit has a 5x5 LED display, using (x, y) notation the top-left
* corner has coordinates (0, 0) and the bottom-right has (4, 4). To make
* the game dynamics more natural, the uses a virtual 50x50 coordinate
* system where top-left is (0, 0) and bottom-right is (49, 49).
*/
#define SCROLL_SPEED K_MSEC(400) /* Text scrolling speed */
#define PIXEL_SIZE 10 /* Virtual coordinates per real pixel */
#define GAME_REFRESH K_MSEC(100) /* Animation refresh rate of the game */
#define PADDLE_ROW 4 /* Real Y coordinate of the paddle */
#define PADDLE_MIN 0 /* Minimum paddle real X coordinate */
#define PADDLE_MAX 3 /* Maximum paddle real X coordinate */
#define BALL_VEL_Y_START -4 /* Default ball vertical speed */
#define BALL_POS_X_MIN 0 /* Maximum ball X coordinate */
#define BALL_POS_X_MAX 49 /* Maximum ball X coordinate */
#define BALL_POS_Y_MIN 0 /* Maximum ball Y coordinate */
#define BALL_POS_Y_MAX 39 /* Maximum ball Y coordinate */
#define START_THRESHOLD K_MSEC(100) /* Max time between A & B press */
#define RESTART_THRESHOLD K_SECONDS(2) /* Time before restart is allowed */
#define REAL_TO_VIRT(r) ((r) * 10)
#define VIRT_TO_REAL(v) ((v) / 10)
/* Ball starting position (just to the left of the paddle mid-point) */
#define BALL_START (struct x_y){ 4, BALL_POS_Y_MAX }
struct x_y {
int x;
int y;
};
enum pong_state {
INIT,
MULTI,
SINGLE,
CONNECTED,
};
static enum pong_state state = INIT;
struct pong_choice {
int val;
const char *str;
};
struct pong_selection {
const struct pong_choice *choice;
size_t choice_count;
void (*complete)(int val);
};
static int select_idx;
static const struct pong_selection *select;
static const struct pong_choice mode_choice[] = {
{ SINGLE, "Single" },
{ MULTI, "Multi" },
};
static bool remote_lost;
static bool started;
static s64_t ended;
static struct k_delayed_work refresh;
/* Semaphore to indicate that there was an update to the display */
static K_SEM_DEFINE(disp_update, 0, 1);
/* X coordinate of the left corner of the paddle */
static volatile int paddle_x = PADDLE_MIN;
/* Ball position */
static struct x_y ball_pos = BALL_START;
/* Ball velocity */
static struct x_y ball_vel = { 0, 0 };
static s64_t a_timestamp;
static s64_t b_timestamp;
#define SOUND_PIN EXT_P0_GPIO_PIN
#define SOUND_PERIOD_PADDLE 200
#define SOUND_PERIOD_WALL 1000
static struct device *pwm;
static enum sound_state {
SOUND_IDLE, /* No sound */
SOUND_PADDLE, /* Ball has hit the paddle */
SOUND_WALL, /* Ball has hit a wall */
} sound_state;
static inline void beep(int period)
{
pwm_pin_set_usec(pwm, SOUND_PIN, period, period / 2, 0);
}
static void sound_set(enum sound_state state)
{
switch (state) {
case SOUND_IDLE:
beep(0);
break;
case SOUND_PADDLE:
beep(SOUND_PERIOD_PADDLE);
break;
case SOUND_WALL:
beep(SOUND_PERIOD_WALL);
break;
}
sound_state = state;
}
static void pong_select(const struct pong_selection *sel)
{
struct mb_display *disp = mb_display_get();
if (select) {
printk("Other selection still busy\n");
return;
}
select = sel;
select_idx = 0;
mb_display_print(disp, MB_DISPLAY_MODE_DEFAULT | MB_DISPLAY_FLAG_LOOP,
SCROLL_SPEED, "%s", select->choice[select_idx].str);
}
static void pong_select_change(void)
{
struct mb_display *disp = mb_display_get();
select_idx = (select_idx + 1) % select->choice_count;
mb_display_print(disp, MB_DISPLAY_MODE_DEFAULT | MB_DISPLAY_FLAG_LOOP,
SCROLL_SPEED, "%s", select->choice[select_idx].str);
}
static void pong_select_complete(void)
{
struct mb_display *disp = mb_display_get();
void (*complete)(int val) = select->complete;
int val = select->choice[select_idx].val;
mb_display_stop(disp);
select = NULL;
complete(val);
}
static void game_init(bool initiator)
{
started = false;
ended = 0;
ball_pos = BALL_START;
if (!initiator) {
ball_pos.y = -1;
}
paddle_x = PADDLE_MIN;
a_timestamp = 0;
b_timestamp = 0;
}
static void mode_selected(int val)
{
struct mb_display *disp = mb_display_get();
state = val;
switch (state) {
case SINGLE:
game_init(true);
k_sem_give(&disp_update);
break;
case MULTI:
ble_connect();
mb_display_print(disp,
MB_DISPLAY_MODE_DEFAULT | MB_DISPLAY_FLAG_LOOP,
SCROLL_SPEED, "Connecting...");
break;
default:
printk("Unknown state %d\n", state);
return;
};
}
static const struct pong_selection mode_selection = {
.choice = mode_choice,
.choice_count = ARRAY_SIZE(mode_choice),
.complete = mode_selected,
};
static bool ball_visible(void)
{
return (ball_pos.y >= BALL_POS_Y_MIN);
}
static void check_start(void)
{
u32_t delta;
u8_t rnd;
if (!a_timestamp || !b_timestamp) {
return;
}
if (a_timestamp > b_timestamp) {
delta = a_timestamp - b_timestamp;
} else {
delta = b_timestamp - a_timestamp;
}
printk("delta %u ms\n", delta);
if (delta > START_THRESHOLD) {
return;
}
ball_vel.y = BALL_VEL_Y_START;
bt_rand(&rnd, sizeof(rnd));
rnd %= 8;
if (a_timestamp > b_timestamp) {
ball_vel.x = 2 + rnd;
} else {
ball_vel.x = -2 - rnd;
}
started = true;
remote_lost = false;
k_delayed_work_submit(&refresh, K_NO_WAIT);
}
static void game_ended(bool won)
{
struct mb_display *disp = mb_display_get();
if (sound_state != SOUND_IDLE) {
sound_set(SOUND_IDLE);
}
remote_lost = won;
ended = k_uptime_get();
started = false;
if (won) {
struct mb_image img = MB_IMAGE({ 0, 1, 0, 1, 0 },
{ 0, 1, 0, 1, 0 },
{ 0, 0, 0, 0, 0 },
{ 1, 0, 0, 0, 1 },
{ 0, 1, 1, 1, 0 });
mb_display_image(disp, MB_DISPLAY_MODE_SINGLE,
RESTART_THRESHOLD, &img, 1);
printk("You won!\n");
} else {
struct mb_image img = MB_IMAGE({ 0, 1, 0, 1, 0 },
{ 0, 1, 0, 1, 0 },
{ 0, 0, 0, 0, 0 },
{ 0, 1, 1, 1, 0 },
{ 1, 0, 0, 0, 1 });
mb_display_image(disp, MB_DISPLAY_MODE_SINGLE,
RESTART_THRESHOLD, &img, 1);
printk("You lost!\n");
}
k_delayed_work_submit(&refresh, RESTART_THRESHOLD);
}
static void game_stack_dump(const struct k_thread *thread, void *user_data)
{
#if defined(CONFIG_THREAD_STACK_INFO)
stack_analyze((char *)user_data, (char *)thread->stack_info.start,
thread->stack_info.size);
#endif
}
static void game_refresh(struct k_work *work)
{
if (sound_state != SOUND_IDLE) {
sound_set(SOUND_IDLE);
k_thread_foreach(game_stack_dump, "Test");
}
if (state == INIT) {
pong_select(&mode_selection);
return;
}
if (ended) {
game_init(state == SINGLE || remote_lost);
k_sem_give(&disp_update);
return;
}
ball_pos.x += ball_vel.x;
ball_pos.y += ball_vel.y;
/* Ball went over to the other side */
if (ball_vel.y < 0 && ball_pos.y < BALL_POS_Y_MIN) {
if (state == SINGLE) {
ball_pos.y = -ball_pos.y;
ball_vel.y = -ball_vel.y;
sound_set(SOUND_WALL);
} else {
ble_send_ball(BALL_POS_X_MAX - ball_pos.x, ball_pos.y,
-ball_vel.x, -ball_vel.y);
k_sem_give(&disp_update);
return;
}
}
/* Check for side-wall collision */
if (ball_pos.x < BALL_POS_X_MIN) {
ball_pos.x = -ball_pos.x;
ball_vel.x = -ball_vel.x;
sound_set(SOUND_WALL);
} else if (ball_pos.x > BALL_POS_X_MAX) {
ball_pos.x = (2 * BALL_POS_X_MAX) - ball_pos.x;
ball_vel.x = -ball_vel.x;
sound_set(SOUND_WALL);
}
/* Ball approaching paddle */
if (ball_vel.y > 0 && ball_pos.y > BALL_POS_Y_MAX) {
if (ball_pos.x < REAL_TO_VIRT(paddle_x) ||
ball_pos.x >= REAL_TO_VIRT(paddle_x + 2)) {
game_ended(false);
if (state == CONNECTED) {
ble_send_lost();
}
return;
}
ball_pos.y = (2 * BALL_POS_Y_MAX) - ball_pos.y;
/* Make the game play gradually harder */
if (ball_vel.y < PIXEL_SIZE) {
ball_vel.y++;
}
ball_vel.y = -ball_vel.y;
sound_set(SOUND_PADDLE);
}
k_delayed_work_submit(&refresh, GAME_REFRESH);
k_sem_give(&disp_update);
}
void pong_ball_received(s8_t x_pos, s8_t y_pos, s8_t x_vel, s8_t y_vel)
{
printk("ball_received(%d, %d, %d, %d)\n", x_pos, y_pos, x_vel, y_vel);
ball_pos.x = x_pos;
ball_pos.y = y_pos;
ball_vel.x = x_vel;
ball_vel.y = y_vel;
k_delayed_work_submit(&refresh, K_NO_WAIT);
}
static void button_pressed(struct device *dev, struct gpio_callback *cb,
u32_t pins)
{
/* Filter out spurious presses */
if (pins & BIT(DT_ALIAS_SW0_GPIOS_PIN)) {
printk("A pressed\n");
if (k_uptime_delta(&a_timestamp) < K_MSEC(100)) {
printk("Too quick A presses\n");
return;
}
} else {
printk("B pressed\n");
if (k_uptime_delta(&b_timestamp) < K_MSEC(100)) {
printk("Too quick B presses\n");
return;
}
}
if (ended && (k_uptime_get() - ended) > RESTART_THRESHOLD) {
k_delayed_work_cancel(&refresh);
game_init(state == SINGLE || remote_lost);
k_sem_give(&disp_update);
return;
}
if (state == MULTI) {
ble_cancel_connect();
state = INIT;
pong_select(&mode_selection);
return;
}
if (pins & BIT(DT_ALIAS_SW0_GPIOS_PIN)) {
if (select) {
pong_select_change();
return;
}
if (!started) {
check_start();
}
if (paddle_x > PADDLE_MIN) {
paddle_x--;
if (!started) {
ball_pos.x -= PIXEL_SIZE;
}
k_sem_give(&disp_update);
}
} else {
if (select) {
pong_select_complete();
return;
}
if (!started) {
check_start();
}
if (paddle_x < PADDLE_MAX) {
paddle_x++;
if (!started) {
ball_pos.x += PIXEL_SIZE;
}
k_sem_give(&disp_update);
}
}
}
void pong_conn_ready(bool initiator)
{
state = CONNECTED;
game_init(initiator);
k_sem_give(&disp_update);
}
void pong_remote_disconnected(void)
{
state = INIT;
k_delayed_work_submit(&refresh, K_SECONDS(1));
}
void pong_remote_lost(void)
{
printk("Remote lost!\n");
game_ended(true);
}
static void configure_buttons(void)
{
static struct gpio_callback button_cb_data;
struct device *gpio;
gpio = device_get_binding(DT_ALIAS_SW0_GPIOS_CONTROLLER);
gpio_pin_configure(gpio, DT_ALIAS_SW0_GPIOS_PIN,
DT_ALIAS_SW0_GPIOS_FLAGS | GPIO_INPUT);
gpio_pin_configure(gpio, DT_ALIAS_SW1_GPIOS_PIN,
DT_ALIAS_SW1_GPIOS_FLAGS | GPIO_INPUT);
gpio_pin_interrupt_configure(gpio, DT_ALIAS_SW0_GPIOS_PIN,
GPIO_INT_EDGE_TO_ACTIVE);
gpio_pin_interrupt_configure(gpio, DT_ALIAS_SW1_GPIOS_PIN,
GPIO_INT_EDGE_TO_ACTIVE);
gpio_init_callback(&button_cb_data, button_pressed,
BIT(DT_ALIAS_SW0_GPIOS_PIN) |
BIT(DT_ALIAS_SW1_GPIOS_PIN));
gpio_add_callback(gpio, &button_cb_data);
}
void main(void)
{
struct mb_display *disp = mb_display_get();
configure_buttons();
k_delayed_work_init(&refresh, game_refresh);
pwm = device_get_binding(DT_INST_0_NORDIC_NRF_SW_PWM_LABEL);
ble_init();
pong_select(&mode_selection);
printk("Started\n");
while (1) {
struct mb_image img = { };
k_sem_take(&disp_update, K_FOREVER);
if (ended) {
continue;
}
img.row[PADDLE_ROW] = (BIT(paddle_x) | BIT(paddle_x + 1));
if (ball_visible()) {
img.row[VIRT_TO_REAL(ball_pos.y)] =
BIT(VIRT_TO_REAL(ball_pos.x));
}
mb_display_image(disp, MB_DISPLAY_MODE_SINGLE,
K_FOREVER, &img, 1);
}
}