130 : Node 130
Balthazar:
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// Initialize the game state.
function init() {
init_game();
init_player1();
init_player2();
init_ball();
// Start game by showing the score.
update_scores(0, 0);
}
// Initialize general game state info.
function init_game() {
var canvas = document.getElementById("stage");
canvas.width = 550;
canvas.height = 400;
_game.width = canvas.width;
_game.height = canvas.height;
// The keymap keeps track of which keys are currently being pressed.
_game.keymap = {};
// How fast the player paddles move.
_game.paddle_speed = 3;
// How fast the ball moves (in x and y direction).
_game.ball_speed = 2;
// Current game state: 'score', 'playing', 'gameover'
_game.state = 'playing';
// Timer for tracking how long to display the score.
_game.score_timer = 0;
// How long to display score (in 60ths of a second).
_game.score_timer_reset = 120;
}
// Start game by showing the score.
update_scores(0, 0);
}
// Initialize general game state info.
function init_game() {
var canvas = document.getElementById("stage");
canvas.width = 550;
canvas.height = 400;
_game.width = canvas.width;
_game.height = canvas.height;
// The keymap keeps track of which keys are currently being pressed.
_game.keymap = {};
// How fast the player paddles move.
_game.paddle_speed = 3;
// How fast the ball moves (in x and y direction).
_game.ball_speed = 2;
// Current game state: 'score', 'playing', 'gameover'
_game.state = 'playing';
// Timer for tracking how long to display the score.
_game.score_timer = 0;
// How long to display score (in 60ths of a second).
_game.score_timer_reset = 120;
}
function update_scores(player1, player2) {
// Update the scores.
_player1.score += player1;
_player2.score += player2;
// Reset the ball.
init_ball();
// Which direction should the next ball be served?
// It should come from the player who just scored the point.
if (player2 > 0) {
_ball.velocity_x *= -1;
}
// Has either player won?
if (_player1.score >= 9 || _player2.score >= 9) {
_game.state = 'gameover';
} else {
_game.state = 'score';
_game.score_timer = _game.score_timer_reset;
}
}
// Has either player won?
if (_player1.score >= 9 || _player2.score >= 9) {
_game.state = 'gameover';
} else {
_game.state = 'score';
_game.score_timer = _game.score_timer_reset;
}
}
// Erase the canvas and draw all the objects.
function draw() {
var canvas = document.getElementById("stage");
var ctx = canvas.getContext("2d");
erase(ctx);
if (_game.state == 'playing') {
draw_player1(ctx);
draw_player2(ctx);
draw_ball(ctx);
} else if (_game.state == 'score') {
draw_player1(ctx);
draw_player2(ctx);
draw_score(ctx);
_game.score_timer--;
if (_game.score_timer <= 0) {
_game.state = 'playing';
}
} else {
draw_score(ctx);
}
}
if (_game.state == 'playing') {
draw_player1(ctx);
draw_player2(ctx);
draw_ball(ctx);
} else if (_game.state == 'score') {
draw_player1(ctx);
draw_player2(ctx);
draw_score(ctx);
_game.score_timer--;
if (_game.score_timer <= 0) {
_game.state = 'playing';
}
} else {
draw_score(ctx);
}
}
script.js: Create a placeholder for draw_score()
// Draw the ball.
function draw_ball(ctx) {
ctx.fillStyle = "white";
ctx.fillRect(_ball.x, _ball.y, _ball.width, _ball.height);
}
function draw_score(ctx) {
// TODO
}
function draw_score(ctx) {
// TODO
}
// This is called ~60 times per second to update the world.
function update_world() {
if (_game.state == 'playing') {
check_input();
update_player1();
update_player2();
update_ball();
}
draw();
requestAnimationFrame(update_world);
}
if (_game.state == 'playing') {
check_input();
update_player1();
update_player2();
update_ball();
}
draw();
requestAnimationFrame(update_world);
}