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Totally Random

Well, it has been a long time since I have blogged here (a year?? really?), but I have been working on a couple of things. I have just quit my job to spend more time with my kids and family, and to spend some time on projects that I have been working on.

The first thing is a company that I have formed with a couple of friends. We are all web developers and are interested in creating interesting things for the internet. One of those projects is a budgeting tool for individuals and business.

So all further news about those two projects will be on the redredred website, and this will continue to be for personal things.

Each animal in EvolveJs is written in a specialised assembly code. This assembly language was designed with some inspiration from Tierra. Each thread is essentially a stack machine and each operation operates on that stack.
An assembly operation is a pair of [operation, operand].

One of the key concepts is in markers used for jumping. To make the animal’s code more robust to modification, all jump targets (such as for loops and branches) are marked as a series of nops, and the jump command specifies the jump target as the number of nops to search for.

So as a concrete example I will show a simple process that can reproduce itself.

This is the 5 label. The nop function does not require an argument, so is by convention set to 0.

["nop",0],["nop",0],["nop",0],["nop",0],["nop",0], //label 5

Now we initialise the read pointer to point to the start of the parent, and the write pointer to point to the end of the parent. The jmp*PtrB functions jump the pointer to the start of the nop template, and the jmp*PtrF functions jump to the end of the nop template. In this code all templates are unique, but it is not necessarily so. The jmp*PtrF functions search forward and wrap around, and the jmp*PtrB functions search backward and wrap around.

["jmpReadPtrB",5], //jmp to start of template 5
["jmpWritePtrF",2], //jmp to end of template 2

Get the parents memory size, allocate memory at the end of the parent, and move the write pointer to the start of the new memory.

["incWritePtr",0], //inc write pointer to start of new animal

The copy loop. Copy from the read pointer to the write pointer, and increment both pointers.

["nop",0], //start copy loop

Push the value for the write pointer and the animals total memory size (including the new child memory) to the stack and compare them using the lt operator.

["pushMemSize",0], //if writeptr < memSize

Then, if write pointer is less than memory size, jump back to start of template 1.
If write pointer is not less than memory size, then the execution pointer gets incremented by 1 + operand (in this case 1), which means that the copying process has finished.

["jmpB",1], //if not finished copying

This is the division loop. When a parent divides, the parent attempts to put the child in the square immediately in front of them. If this position is already occupied, then division fails, and the parent gets to try again.

["nop",0],["nop",0],["nop",0],["nop",0],["nop",0],["nop",0], //template 6

Divide attempts division and pushes a boolean result onto the stack indicating success. If division succeeds, then jump all the way back to template 5, and start making a new baby.

["jmpB",5], //if division successful

Here, we are using one of those nop templates to store data.
The memory pointer jumps to the first memory address in the 6template. The data that is stored in the operand is pushed onto the stack, incremented, stored back in the memory slot and compared to 4 (number of cardinal directions)

["jmpMemPtrB",6],// jump the mem pointer to a location to store some data

If it has already tried this 4 times, then this animal is surrounded and can't reproduce at the moment. So it sleeps, and we reset the counter. Otherwise, the ifdo,3 increments the execution pointer by an extra 3.


The divide didn't work, try again facing in a new direction.

["turnR",0], //turn around and try again

The end tag


This application is a “proof of concept” evolution simulator. Each animal (process) has the following properties

  • Memory: This is both readable and writable memory addresses starting from address 0 for each animal.
  • Threads: Each animal can have multiple threads that communicate via it’s memory.
  • CpuTime: Each animal is granted cputime by it’s parent when it is born, and after that is given cputime by the environment (like sunshine) each cycle.
  • Position: Each animal has a current position in the grid
  • Direction: Each animal is pointing in a certain direction (this is not currently shown in the display.

Each thread in each animal has the following properties:

  • Stack: this is essentially current memory. Operations can put information on the stack, manipulate the top item on the stack, or pop information off the stack.
  • Execution Pointer: Each thread is executing the same program, but potentially at a different address (different function) in memory.
  • Read Pointer and Write Pointer: These are used for copying operations.
  • Memory Pointer: This is used for writing operands only.
  • Speed: An animal can choose to operate faster, multiple operations per second. This is expensive for the animal.
  • SleepCycles: The thread can sleep for a set number of cycles. It will be woken when this counter reaches 0.

There have so far been two Ancestors created:

  1. A simple non-mobile vegetable. This has a single thread that is devoted to reproduction.
    Once all 8 slots around the animal are full, it sleeps for a period and then checks again.
  2. A simple mobile vegetable. This has two threads: one is devoted to reproduction, the other moves in a straight line forever.
    When it reproduces, it turns right.

Animals reproduce by allocating memory at the end of their memory, then copying their code into the new memory, and then dividing the new memory.
This creates a new process.
The copying process has a non-0 random chance of failing to accurately copy the data requested.
This results in the child not always being the same as the parent, and the chance for evolution is created.
Successful species (when a species has had enough animals with the same code, occurs at powers of 10) are sent to the server.
When the application starts it requests the 10 best animals from the server.
Things you can do:

  • Click on an individual to see information about it on the “Process Details” tab
  • View code of species on server to see what has evolved from the “Progenitors”

Future features:

  • Ability to examine the code of any individual.
  • Allow the user to insert new processes (with new code) into the environment.

Liam turned two recently and he had a birthday party. Some of his friends from childcare came and we all had lots of fun. I was a bit worried about what it would be like having 10-15 2 year olds at our house, but nothing major was broken and we had lots of time to play and to talk with the adults too!

Liam is fully into sentences now. His first sentence (about August last year) was on one of my Fridays off, I was lying in bed and he came in and asked "Chase pigeons in park today?" (still one of his favourite hobbies). How could I say no? He has five very good friends that he has met at childcarre. His first girlfriend (Molly) moved away to Brighton, but she was able to come to his party and they instantly fell into their old play and trashed the back yard and their clothes. Isabella and Hamish are high-energy twins, Lola is Liams new girlfriend at childcare and Mac is his big friend (he weighs about 50% more than Liam…)

It isn't long until we have a new baby and we have been trying to prepare Liam for it. He knows that "mummy has a baby in there", but he doesn't really grasp that it is going to come out and wreck his life. I feel sorry for him, not realising the huge changes that are coming. It has been a great 2 years though.

Here are some photos from when we were in japan recently and from his birthday party on the weekend.


IMG 6255IMG 6254IMG 6250IMG 6249IMG 6248IMG 6247IMG 6243 2

I have been playing with javascript a bit lately, testing out techniques that I might use for doing a full web 2.0 business application (if any clients would agree…). The application that I have written is a game along the same sort of lines as RoboCode. 

It allows users to implement "animals" in custom written assembly code ("genomes"), which compete for resources and can move around and eat each other. I have currently written two simple genome, a vegetable (it doesn't move) and a predator (it does move). They are both using almost the simplest algorithms for each of these tasks as possible.

The animals run virtual cpu's and also implement virtual threading. The predator animal has a reproductive thread and a movement thread. The vegetable has only a reproductive thread. And as the last real feature, the animals also have a non-zero chance of their mem-copy commands (part of the requirement of reproduction) failing to copy correctly. This introduces mutations and hopefully mutation.

The javascript application is backed on the server by a ruby on rails application that stores successful animals (animals that survive to reproduce).

I have a few problems with the current implementation that limits it's usefulness.

  1. First, the application is pretty slow. It runs at about 600hz on my computer in firefox 3b2. (This means that it executes 500 virtual cpu instructions per second.) Compare this to my actual machine running at 2 billion instructions per second, and there is a factor of 4 million difference. Some of this can be explained by the fact that each virtual instruction is implemented as a block of javascript code that does stuff to memory in the cpu. Some more is probably explained by me not using javascript to its full potential. The rest must be explained by javascript being s l o w. I have used firebug to do some profiling of the code to find hotspots and have been able to find some issues. To make the evolution part of the application do anything useful it would need to be 10x faster at least. But I think that to make it a factor of 10 faster i would need to radically change the architecture.
  2. Another issue is that the application occasionally just freezes. I imagine it is doing some sort of garbage collection in the background. I would love to be able to get more control over this, so that I could see what was happening, or at least predict when it might happen.

These are the same issues that I would face implementing a large javascript client in a web 2.0 application, so I am glad to have found them now rather than later.

An early alpha version (where it isn't possible to inject new animals into the application, except by editing the source directly, and the server communication isn't working properly) is available. The source is all on the page in easily read code, if anyone is interested.

Firefox is a much better browser than MS Internet Explorer. It has lots of little benefits for me:

  • Tabbed browsing
  • More standards compliant
  • Easier to develop in
  • Better bookmark management

and there are plenty more. But the main benefit is the extensions. The things that you can do with them are amazing. Literally changing your browser into whatever you want it to be. Optimising your web browsing experience for whatever you think is easiest.

Here is a list of the extensions that I have installed:

Challenge Manager is now ready for public use. It is currently being used on selfPortraitChallenge and Whipup.

If you are happy with using this plugin, please link back to me on your blog, and put your address in the comments. I'll add a blog entry soon listing all the people that are using it.

Please put all feedback into the comments. I will try to be prompt with replies.


Well, it turned out to be remarkably simple to switch my not very technically adept parents from Windows XP to Ubuntu (Breezy Badger). We did this on the basis that it was getting increasingly difficult to manage their computer difficulties from Melbourne, and their Windows XP installation was incredibly spamware and adware ridden.

So at the moment I have put Ubuntu on as a second boot option, just in case they ABSOLUTELY NEED TO use windows. But they tell me that they are only using Ubuntu.  In Linux, I have given their user accounts the standard (low) level of access, and I have made sure that I can get ssh access externally. Now I just need to set up VNC and dynamic domain registration so that I don't have to keep getting dad to lookup his modems external IP address.

Mark that one up as another successful switch to Linux. It was a lot easier than I thought. Their main applications that they used are Firefox, Outlook and some Microsoft Word. 

Liam spent some time with Grandma in Canberra at Easter


We love being parents to Liam more and more each day. He continues to surprise and delight us with his ever emerging personality. Gone is the redness of his newborn skin; his skin is now a pale chickeny colour, so I have started to call him chicken chop.Overall, I still think he's pretty laid back, and is happy most of the time. In the past couple of weeks, his development seems to have surged: all of a sudden he has become quite a talker, starting out cooing, and now actively gurgling with me every day. In the evening he talks earnestly of his big day, his back resting on Jon's legs and looking into Jon's face. I have attached a toy, which contains a mirror, among other things, to one side of his cot. Encouraged by the smiling face staring back at him, he sometimes wakes me in the mornings by talking to himself in the cot until I get up. And another recent observation is during 'tummy time' on the rug (to build his neck and back muscles). He now manages easily to hold his head up in the prone position, and can, just, commando crawl toward my voice and a toy. By the end of 5 minutes, though, he's pretty exhausted and a frustrated grizzle tells me that he's had enough. Recently, Liam's helped us to realise just how much he enjoys his evening bath. Observing him beforehand as we undress him on the change table, he gives us wide, eager eyes; sticks his tongue out, and waves his arms and legs madly as if splashing in the bath. And he has also discovered the thrill of new textures in his mouth. His fist is frequently in his mouth, making loud sucking noises, and he'll try to suck on my hand when I hold him upright to burp after a feed. But he hasn't quite got the hang of holding on to toys and bringing them up to his mouth. The saga of managing his food intolerances continues. I've been keeping a food diary with the aim of identifying – and then avoiding – foods to which he is sensitive. I'm pretty sure one of the culprits is one or more of the additives in chocolate, so regrettably have had to eliminate chocolate from my diet for the foreseeable future. At its worst, he's had a couple of bouts of bright red blood specks in his poo, which we suspect may be caused by anal fissures (tears) as he strains, due to a severely irritated gut. Poor love – I have planned to return to the paediatrician, who I think might refer me to a paediatric allergist. At 6 months of age, if it hasn't resolved, it may require some skin prick tests to identify the food/s he is allergic to. IMG_2860 (Large) IMG_2451 IMG_2518 IMG_2535 IMG_2543 IMG_2563 IMG_2577 IMG_2583 IMG_2707 IMG_2732 IMG_2735 IMG_2762 IMG_2781 IMG_2786 IMG_2801 IMG_2808 We are all very well. At this stage, we plan to drive to Canberra for Easter; not quite sure where we'll stay yet, but will let you know. Finally, here are some photos. There are so many I want to include – I might do it over two emails. Lots of love Jon, Tam and Liam xxx

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