Initial import

1 files changed, 251 insertions, 0 deletions

diff --git a/js/game.js b/js/game.js
new file mode 100644
index 0000000..85b0f91
--- /dev/null
+++ b/js/game.js
@@ -0,0 +1,251 @@
+class Game {
+    constructor(canvas) {
+        this.canvas = canvas;
+        this.ctx = canvas.getContext("2d");
+
+        // override this for a differnt size
+        this.width = 320;
+        this.height = 240;
+
+        // override this with your data to be loaded:
+        //
+        // { id: "file.png" }
+        //
+        // Supports .png, .ogg and .json files.
+        //
+        // and also override dataSize with:
+        //
+        // this.dataSize = Object.keys(this.data).length
+        //
+        this.data = {};
+        this.dataSize = 0;
+
+        // override to change keys
+        this.controls = {
+            80: "pause",
+            83: "start",
+            37: "left",
+            38: "up",
+            39: "right",
+            40: "down",
+            90: "a",
+            88: "b"
+        };
+
+        this.scale = 1;
+
+        // will store the resouces indexed by id
+        this.res = {};
+        this.resSize = 0;
+
+        // override if you want to change the limit
+        // defaults to 8 "channels"
+        this.playLimit = 8;
+        this.playCount = 0;
+
+        // test to see if a key is down or not
+        this.keys = {
+            pause: false,
+            start: false,
+            left: false,
+            up: false,
+            right: false,
+            down: false,
+            a: false,
+            b: false
+        };
+
+        this.minFps = 60;
+        this.then = -1 / 60;
+
+        this.loadingError = undefined;
+    }
+
+    start() {
+        this.canvas.style.background = "rgb(21, 21, 21)";
+        this.resize();
+
+        window.onresize = (ev) => {
+            this.resize();
+        };
+
+        this.loader();
+    }
+
+    // override this
+    init() {}
+    // override this
+    update(dt) {}
+    // override this
+    draw() {}
+
+    _update(dt) {}
+    _draw() {}
+
+    resize() {
+        this.scale = Math.floor(window.innerHeight / this.height);
+        this.canvas.width = this.width * this.scale;
+        this.canvas.height = this.height * this.scale;
+
+        if (this.ctx != undefined) {
+            this.ctx.imageSmoothingEnabled = false;
+        }
+    }
+
+    loop(now) {
+        let dt = Math.min(1 / this.minFps, now - this.then);
+        this._update(dt);
+
+        this._draw();
+
+        this.then = now;
+        requestAnimationFrame((now) => {
+            this.loop(now)
+        });
+    }
+
+    loader() {
+        this._draw = this.drawLoading;
+        this.loop(0);
+
+        const onError = (ev) => {
+            console.log(ev);
+            this.loadingError = true;
+        };
+
+        for (const id in this.data) {
+            if (this.data[id].indexOf(".png") != -1) {
+                this.res[id] = new Image();
+                this.res[id].src = this.data[id];
+                this.res[id].onerror = onError
+                this.res[id].onload = (ev) => {
+                    this.res[id].onload = null;
+                    ev.currentTarget.removeEventListener("error", onError);
+                    this.resSize += 1;
+                };
+                continue;
+            }
+            if (this.data[id].indexOf(".ogg") != -1) {
+                this.res[id] = new Audio();
+                this.res[id].src = this.data[id];
+                this.res[id].autoplay = false;
+                this.res[id].addEventListener("error", onError);
+                this.res[id].oncanplaythrough = (ev) => {
+                    this.res[id].oncanplaythrough = null;
+                    ev.currentTarget.removeEventListener("error", onError);
+                    this.resSize += 1;
+                };
+                continue;
+            }
+            if (this.data[id].indexOf(".json") != -1) {
+                let xhr = new window.XMLHttpRequest();
+                xhr.open("GET", this.data[id]);
+                xhr.responseType = "json";
+                xhr.addEventListener("error", onError);
+                xhr.onload = (ev) => {
+                    ev.currentTarget.removeEventListener("error", onError);
+                    xhr.onload = null;
+                    if (xhr.status == 200) {
+                        this.res[id] = xhr.response;
+                        this.resSize += 1;
+                    } else {
+                        console.log(ev);
+                        this.loadingError = true;
+                    }
+                };
+                xhr.send();
+                continue;
+            }
+        }
+    }
+
+    // erases the canvas and sets the scaling
+    drawStart() {
+        this.ctx.clearRect(0, 0, this.ctx.canvas.width, this.ctx.canvas.height);
+        this.ctx.save();
+        this.ctx.scale(this.scale, this.scale);
+    }
+
+    // restores the context
+    drawEnd() {
+        this.ctx.restore();
+    }
+
+    // won't use drawStart/drawEnd because may render regular fonts
+    drawLoading() {
+        this.ctx.clearRect(0, 0, this.ctx.canvas.width, this.ctx.canvas.height);
+        this.ctx.save();
+
+        // height of the loading bar
+        const h = 6;
+
+        if (this.loadingError == true) {
+            this.ctx.fillStyle = "rgb(255, 255, 255)";
+            this.ctx.font = "caption";
+            this.ctx.fillText(
+                "ERROR Loading Resources",
+                Math.floor(this.width * 0.1 * this.scale),
+                Math.floor((this.height / 2 - h - 2) * this.scale)
+            );
+        }
+
+        this.ctx.scale(this.scale, this.scale);
+
+        this.ctx.fillStyle = "rgb(128, 128, 128)";
+        this.ctx.fillRect(Math.floor(this.width * 0.1), Math.floor(this.height / 2) - h, this.width - Math.floor(this.width * 0.2), h);
+        this.ctx.fillStyle = "rgb(255, 255, 255)";
+        this.ctx.fillRect(Math.floor(this.width * 0.1), Math.floor(this.height / 2) - h, (
+            Math.floor(this.resSize * (this.width - Math.floor(this.width * 0.2)) / this.dataSize)
+        ), h);
+
+        this.ctx.restore();
+
+        // we don't do this on update because we want
+        // the progress bar to finish drawing
+        if (this.resSize == this.dataSize) {
+            console.log("Loader done");
+
+            document.addEventListener("keydown", (ev) => {
+                this.keyDown(ev)
+            }, false);
+            document.addEventListener("keyup", (ev) => {
+                this.keyUp(ev)
+            }, false);
+
+            this.init();
+            this._update = this.update;
+            this._draw = this.draw;
+        }
+    }
+
+    playSnd(playable, loop, clone) {
+        if (this.playCount < this.playLimit) {
+            this.playCount += 1;
+
+            if (clone || false) {
+                playable = playable.cloneNode(true)
+            }
+            playable.onended = (ev) => {
+                playable.onended = null;
+                this.playCount -= 1;
+            };
+            playable.loop = loop || false;
+            playable.play();
+        }
+    }
+
+    keyDown(ev) {
+        let key = this.controls[ev.keyCode];
+        if (key != undefined) {
+            this.keys[key] = true;
+            ev.preventDefault();
+        }
+    }
+
+    keyUp(ev) {
+        let key = this.controls[ev.keyCode];
+        if (key != undefined) {
+            this.keys[key] = false;
+        }
+    }
+}