/* JSGoL - Game of Death in Javascript 2007 - Mohit Muthanna How to embed this game into your page:

*/ // The Grid object. This is basically a wrapper around a 2D Canvas object. function Grid(tag, grid_width, grid_height) { this.canvas = document.getElementById(tag); this.ctx = this.canvas.getContext("2d"); this.grid_height = grid_height; this.grid_width = grid_width; } Grid.prototype.BlockHeight = function () { return this.canvas.height / this.grid_height; } Grid.prototype.BlockWidth = function () { return this.canvas.width / this.grid_width; } Grid.prototype.SetFillStyle = function (style) { this.ctx.fillStyle = style; } Grid.prototype.Plot = function (x, y) { this.ctx.fillRect(x * this.BlockWidth(), y * this.BlockHeight(), this.BlockWidth(), this.BlockHeight()); this.Stroke(x, y); } Grid.prototype.UnPlot = function (x, y) { this.ctx.clearRect(x * this.BlockWidth(), y * this.BlockHeight(), this.BlockWidth(), this.BlockHeight()); this.Stroke(x, y); } Grid.prototype.Stroke = function (x, y) { this.ctx.strokeRect(x * this.BlockWidth(), y * this.BlockHeight(), this.BlockWidth(), this.BlockHeight()); } Grid.prototype.GetCellX = function (x) { return Math.floor((x - this.canvas.offsetLeft) / this.BlockWidth()); } Grid.prototype.GetCellY = function (y) { return Math.floor((y - this.canvas.offsetTop) / this.BlockHeight()); } // CellMap: A representaion of the board using multidimensional arrays. function CellMap(width, height) { this.width = width; this.height = height; // Empty the Map this.Clear() } CellMap.prototype.Width = function () { return this.width; } CellMap.prototype.Height = function () { return this.height; } CellMap.prototype.Clear = function () { this.cells = new Array(this.width); for (w = 0; w < this.width; w++) { this.cells[w] = new Array(this.height); for (h = 0; h < this.height; h++) { this.cells[w][h] = false; } } } CellMap.prototype.ValidateCoordinates = function (x, y) { if (x >= this.width || x < 0) return false; if (y >= this.height || y < 0) return false; return true; } CellMap.prototype.Set = function (x, y, value) { if (!this.ValidateCoordinates(x, y)) throw new Error("Coordinates out of range."); this.cells[x][y] = value; } CellMap.prototype.Get = function (x, y) { if (this.ValidateCoordinates(x, y) == false) return false; else return this.cells[x][y]; } // GoL: The Game of Death. Business Logic (really). function GoL(grid) { this.grid = grid; this.grid.canvas.gol = this; this.grid.canvas.onmousedown = this.MouseDown; this.grid.canvas.onmouseup = this.MouseUp; this.grid.canvas.onmousemove = this.MouseMove; this.width = this.grid.grid_width; this.height = this.grid.grid_height; this.cellmap = new CellMap(this.width, this.height); this.cellmap.Clear(); this.dragging = false; this.running = false; } GoL.prototype.GiveBirth = function (x, y) { this.cellmap.Set(x, y, true); } GoL.prototype.Die = function (x, y) { this.cellmap.Set(x, y, false); } GoL.prototype.Occupied = function (x, y) { return this.cellmap.Get(x, y); } GoL.prototype.Draw = function () { for (x = 0; x < this.cellmap.Width(); x++) { for (y = 0; y < this.cellmap.Height(); y++) { if (this.cellmap.Get(x, y)) { this.grid.Plot(x, y); } else { this.grid.UnPlot(x, y); } } } } // Return the number of live neighbours, given a // cell. GoL.prototype.NeighbourCount = function (x, y) { count = 0; // Get top left to top right, and bottom left // to bottom right. for (w = -1; w < 2; w++) { if (this.cellmap.Get(x + w, y - 1)) count++; if (this.cellmap.Get(x + w, y + 1)) count++; } // Get left and right cells if (this.cellmap.Get(x - 1, y)) count++; if (this.cellmap.Get(x + 1, y)) count++; return count; } GoL.prototype.NextGeneration = function () { for (x = 0; x < this.width; x++) { for (y = 0; y < this.height; y++) { // Get number of neighbours neighbours = this.NeighbourCount(x, y); // If the cell is occupied if (this.Occupied(x, y)) { // Die of overcrowding if (neighbours >= 4 && neighbours <= 8) this.Die(x, y); // Die of loneliness if (neighbours == 0 || neighbours == 1) this.Die(x, y); } else { // Be born if (neighbours == 3) { this.GiveBirth(x, y, true); } } } } } GoL.prototype.Clicked = function (e) { x = this.grid.GetCellX(e.clientX); y = this.grid.GetCellY(e.clientY); this.GiveBirth(x, y); this.grid.Plot(x, y); } GoL.prototype.MouseDown = function (e) { this.gol.dragging = true; this.gol.Clicked(e); } GoL.prototype.MouseUp = function (e) { this.gol.dragging = false; } GoL.prototype.MouseMove = function (e) { if (this.gol.dragging) this.gol.Clicked(e); } GoL.prototype.StartGame = function () { this.running = true; this.Run(this); } GoL.prototype.ClearGame = function () { this.cellmap.Clear(); this.Draw(); } GoL.prototype.StopGame = function () { this.running = false; } GoL.prototype.Run = function (a_gol) { a_gol.Draw(); if (a_gol.running) setTimeout (function () {a_gol.Run(a_gol)}, 1000); a_gol.NextGeneration(); }