Block Breaker

I’ve been following a course on Udemy on game development with Unity.

Block Breaker is an Arkanoid/Breakout clone.

I changed the script to move the paddle with the arrow keys.

You start the game by clicking on the screen or pressing the spacebar key.

Click here to play.

Tilemaps Day 2

This evening I continued experimenting with designing pixelated tiles at a 32X32 resolution.

My “Hothead” font is available for sale on Creative Fabrica here.


Lately I’ve been following some Udemy courses, particularly the one on 2D game Design with Unity.

In the course I started learning about tilemaps and so I started drawing some of my own today.

For prototyping the tilemap I made a sample scene, which I found out was useful as an illustration photo for one of my new fonts: Hothead.

It’s fun when the different skills come together and supplement each other.

My new font is available on DaFont here.

EAN Barcodes and GEPIR

A simple search application for searching through the Product Open Database can be found here.

I’ve been working more on Code128 by writing programs that both create Code128 from strings directly and making my own Code128 font based on the Wikipedia entry.

Then I became curious about the EAN13 symbology and thought I’d have a go at making an EAN SVG program that takes the first twelve digits of an EAN and creates a barcode in SVG format.

The Java code can be found on github here.

Here’s some of the more interesting functions.

public class EAN {

	HashMap<String, String[]> table = new HashMap<String, String[]>();
	String lgr;
	String number;
	String binaryString;
	int checksum;

	public static String binToDecSeq(String seq) {
		String s = "";
		int sum = 1;
		for(int i = 1; i < seq.length(); i++) {
			if(seq.charAt(i) != seq.charAt(i - 1)) {
				s = s + sum;
				sum = 1;
			} else {
			if(i == seq.length() - 1) {
				s = s + sum;
		return s;

	public static String createBinaryString(String number, String lgr, HashMap<String, String[]> table) {
		String binaryString = "";
		lgr = lgr + "RRRRRR";
		number = number.substring(1);
		binaryString += "101";
		for(int i = 0; i < number.length(); i++) {
			binaryString += table.get("" + lgr.charAt(i))[Character.getNumericValue(number.charAt(i))];
			if(i == 5)
				binaryString += "01010";
		binaryString += "101";
		return binaryString;
	public static HashMap<String, String[]> makeTable() {
		HashMap<String, String[]> table = new HashMap<String, String[]>();
		table.put("L", new String[] { "0001101", "0011001", "0010011", "0111101", "0100011", "0110001",
				"0101111", "0111011", "0110111", "0001011" });
		table.put("R", new String[] { "1110010", "1100110", "1101100", "1000010", "1011100", "1001110",
				"1010000", "1000100", "1001000", "1110100" });
		table.put("G", new String[] { "0100111", "0110011", "0011011", "0100001", "0011101", "0111001",
				"0000101", "0010001", "0001001", "0010111" });
		return table;
	public static int calculateChecksum(String twelveDigits) {
		int checksum = 0;
		for(int i = 0; i < twelveDigits.length() && i < 12; i++) {
			String s = "" + twelveDigits.charAt(i);
			if(i % 2 == 0) {
				checksum += Integer.parseInt(s) * 1;
			} else {
				checksum += Integer.parseInt(s) * 3;
		checksum = 10 - (checksum % 10);
		return checksum;


Web-Drafter update: Color Picker

My very tiny vector graphics application is improving at a snail pace.

I managed to make a colour picker using jQuery and the HTML range input element.

The code isn’t exactly succinct, but it gets the job done.

Because the program is growing larger, I’m trying to use the OOP facets of JavaScript and put the functions in their respective objects as much as possible, the loose functions in the posfunc.js file creates the dialog:

function color_selector_form(color) {
    frgb = color.get_fill_rgb();
    srgb = color.get_stroke_rgb();

    var red_slider = "<input class='fill_slider' id='red_slider' value="+frgb[0]+" type=\"range\" min=\"0\" max=\"255\"> <br> <div id='rfval' >"+frgb[0]+"</div><br> ";
    var green_slider = "<input class='fill_slider' id='green_slider' value="+frgb[1]+" type=\"range\" min=\"0\" max=\"255\"> <br> <div id='gfval' >"+frgb[1]+"</div><br>";
    var blue_slider = "<input class='fill_slider' id='blue_slider' value="+frgb[2]+" type=\"range\" min=\"0\" max=\"255\"> <br> <div id='bfval' >"+frgb[2]+"</div><br>";
    var fcbox = "<span id=\"fillbox\" style=\"background-color: "+color.fill+"; display: block; height: 50px; width: 50px;\">&nbsp</span>";

    var red_stroke_slider = "<input class='stroke_slider' id='red_stroke_slider' value="+srgb[0]+" type=\"range\" min=\"0\" max=\"255\"> <br> <div id='rsval' >"+srgb[0]+"</div><br> ";
    var green_stroke_slider = "<input class='stroke_slider' id='green_stroke_slider' value="+srgb[1]+" type=\"range\" min=\"0\" max=\"255\"> <br> <div id='gsval' >"+srgb[1]+"</div><br>";
    var blue_stroke_slider = "<input class='stroke_slider' id='blue_stroke_slider' value="+srgb[2]+" type=\"range\" min=\"0\" max=\"255\"> <br> <div id='bsval' >"+srgb[2]+"</div><br>";
    var scbox = "<span id=\"strokebox\" style=\"background-color: "+color.stroke+"; display: block; height: 50px; width: 50px;\">&nbsp</span>";

    var retval = "<table><tr><td>Fill<br><br>";
    retval += "Red: <br>" + red_slider + "Green: <br>" + green_slider + "Blue: <br>" + blue_slider + "<br>" + fcbox;
    retval += "</td><td>&nbsp&nbsp&nbsp</td><td>Stroke<br><br>";
    retval += "Red: <br>" + red_stroke_slider + "Green: <br>" + green_stroke_slider + "Blue: <br>" + blue_stroke_slider + "<br>" + scbox;
    retval += "</td></tr></table>";
    return retval;

While the pos.js has the $(document).ready() functions for the dynamically created elements:

jQuery(document).on("change mousemove", ".fill_slider", function() {
   selected_color.update_fill(jQuery(this).val(), jQuery(this).attr("id"));
   var id = jQuery(this).attr("id");
   //console.log(id + " " +jQuery(this).val());
   if(id.substring(1, 2) == "r") {
       } else  if(id.substring(1, 2) == "g") {
       } else  if(id.substring(1, 2) == "b") {

Which in turn calls the appropriate methods in the MyColor object.

MyColor.prototype.update_fill = function(colorval, id) {
    var hexredval = parseInt(colorval).toString(16);
    if(hexredval.length < 2)
        hexredval = "0" + hexredval;
    var channel = id.substring(0,1);
    if(channel == "r")
        this.fill = (this.fill.substring(0, 1) + hexredval.substring(0, 2) + this.fill.substring(3)).toUpperCase();
    else if(channel == "g")
        this.fill = (this.fill.substring(0, 3) + hexredval.substring(0, 2) + this.fill.substring(5)).toUpperCase();
    else if(channel == "b")
        this.fill = (this.fill.substring(0, 5) + hexredval.substring(0, 2)).toUpperCase();
    jQuery("#" + channel + "fval").html(colorval);
    jQuery("#fillbox").css("background-color", this.fill);

As you can see, the code isn’t really DRY, but I find that making a clumsy solution is a great way to start a project and get anything done whatsoever, and then improve on it (or just keep it until it becomes cluttered).

Interactive jQuery Menu

A few days ago I was asked to update the layout of the website for a store I used to work at.

I thought this was a good chance to get to know jQuery animations, so I put together a bunch of stock images as background, edited pictures of frames and put some text in the frames for the icons.

I worked with artboards in Affinity Designer so I could export multiple images to different files, I also worked with groups and a transparent background so I could make .png files of the frames and put them on top of the background images.

That way I used the background-image css property, with display set to block and could superimpose a png with transparency over another image.

With jQuery I selected all images, where each image has a class “RT” and I used the reserved word this to select the particular instance for mouseover and mouseleave events.

With this I managed to make a fun little menu where the frame with the text grows and shrinks according to mouse-events.

The result can be seen here.


I noticed that my programming page was sadly empty.

So to have some actual content I started writing a bit about C so I can rehash and remind myself of what I’ve learned about the C programming language.

It’s some really basic stuff, and of course, I’ve made programs to do a lot more than just print to terminal and work on simple variables, but I have to start somewhere when I write about that stuff.

Let's start at the very beginning. 

A very good place to start.

When you read you begin with ABC.

When you code you compile with G C C