Can I look after a goldfish?

The short answer is no. Good bye!

Still here? Oh, well, you see I would love to look after a living creature, but unfortunately I would be a bad parent. I would forget to feed it, or neglect its little tank and turn its environment into a dank, poisonous and murky abyss even worse than Darlington. With this self-realisation comes wisdom though, for now I seek my animal companionship through virtual pets.

My current favourite is iQuarium by Infinite Dreams for Android.

My pet fish, John.
This is a really beautiful app. The fish looks very lifelike and the developers have clearly spent a lot of time making the fish move like a real animal. Unlike in many virtual pet apps, there are no gimmicks. You simply have to remember to feed your fish each day and that's it. There are no daft games to play to increase its 'happyness', and no muck to clear out. Each day you just get to watch your fish swimming around its virtual world. It is very relaxing.

The way you treat your fish will affect its personality, apparently. I do not know if this is true, or not, because so far I have been treating my fish very well. John is a seemingly happy and well-adjusted four-week old fish.

You can interact with your pet. If you press on your screen he will follow your finger. If you tap him he will turn and stare at you. Other than that, your fish is its own person and will do its own thing.

The longer you keep your fish, the more points you score. Various new artifacts, plants and backgrounds are available the longer you play.

Here you can see John hard at work coming up with ideas for his own blog.
If you are looking for a realistic fish simulator with no gimmicks then to look at iQuarium for Android. It is a shame that there is no Windows 10 version though.

+1 Geek experience point awarded to Infinite Dreams.

If you are still here, then you might like to read all about that time I was the god of my own planet, or have a look at my other virtual pet posts.


DesignEvo

Candy from PearlMountain got in touch recently and asked me to do a review of DesignEvo. I don't often get asked to review software. I prefer to showcase stuff I find interesting as and when I find it myself, but Candy asked nicely, so here we go.

DesignEvo is a very easy to use tool for creating vector logos. After a brief tutorial you are deposited on a blank 500 x 500 canvas with three tabs one the left hand side. Candy promises me professional looking logos in seconds and she doesn't disappoint.

A very intuitive interface with over one million icons available through search.

There are three main elements to your design: Icons, text and shapes. These can then be freely arranged on your canvas. I had a go at creating a new logo for HaveSpellWillTravel. I started my stop watch at the end of the tutorial and I had produced the following design after 48 seconds.

Let's check those credentials again. "Professional-looking logo" - CHECK. Created in seconds - YOU BET! 48 seconds in fact.
Some really nice features include:

  • Dotty green guidelines on the canvas to help you position your stuff.
  • The ability to download your logo - for FREE in JPEG, PNG and transparent format, although they do ask that you credit the source back to DesignEvo, which I guess is only fair. A link along the lines of: Logo made with DesignEvo is required.
  • The preview feature allows you to see how your logo as it would appear on your headed notepaper or tee-shirt.

See how your logo would look on your employees' chests, or in the foyer of your HQ in Silicon Valley. 
Our review summary: This is a really easy to use tool that would be perfect for school projects.

Our rating: 5/5 and +1 Geek Experience Point for PearlMountain.

If you came here looking for logos, then you might like our reviews of other logo software. If you just parachuted in looking for something fun, then you might like this stuff or that stuff. Either way, I'll see you soon for more geeky stuff.

My most pointless IFTTT applets

IFTTT is a service for linking various services together. Literally, if this happens, then that will happen. If you are reading this article from a link on Twitter, G+, Tumbler, Pinterest or elsewhere, it is likely that an IFTTT applet put it there. I've been using IFTTT for years and I have several hundred applets automating my digital life.

This post is about some of the most pointless applets, some of which I still use.

Used in conjunction with with the 'mute your phone at bedtime' applet. I quickly stopped using this one because it would always set the volume to 'very high'. I certainly miss the 'quiet times' feature of my Lumia 950.

This one is cool, but pointless. You get to store all of your tweets in a text file for, you know, reasons.

Daily pictures from NASA on your homescreen. I stopped using this one because I much prefer a simple solid colour background to my phone whereas the NASA pictures can make your phone look cluttered. Again, I miss my Lumia 950 for its live tiles and transparent icrons. The Microsoft launcher is a good replacement for Android, and you also get the Bing daily pictures on your homescreen if that's a thing you like.

Ok, so when an email arrived in my inbox, the LaMetric stopwatch would start time. Presumably I did this so I could time how long it took me to delete, I mean respond to import work messages. I soon found this an annoying distraction and turned it on. I can see how this might be a useful feature someday, again, you know, because of reasons.

Pocket is great. Here I can save the links people tweet directly into Pocket. I'm still using this one, the only problem is I don't actually think I every follow up on many of the links. My pocket is hundreds of articles deep and growing. A cull is needed soon.

This one is totally not a pointless applet at all. If an email arrives then the attachments are safely stored away. I don't need to trawl through days and days of junk in my inbox, the files are waiting for me on all my devices whenever I need them (along with a large proportion of junk).

It sounded good at first. Every new item on your Alexa shopping list automatically gets a new page in OneNote. What's the problem? I delete things from my shopping list when I have bought them, but not from OneNote. My OneNote now has eighteen pages called 'onions'.

This one is switched on, but I don't actually use the Alexa 'To-Do'. I use Wunderlist instead.
So, there's eight pointless applets but there are so many potential good ones waiting to be made. That's all from me, I've got a gutter to clear. If you want to stay and read more vaguely amusing tech stuff, then you might like to read about some clock programs, or fun stuff Cortana can do.

Amazon Echo and LaMetric Time



The Amazon Echo is a smart speaker system with digital assistant. She responds to the wake-up word 'Alexa' and her features include music streaming from Spotify, internet radio, shopping lists, alarms, timers, reminders, weather and news updates, as well as one-sided conversations. The sound quality is really very good, and I do love watching the glowing light spin as Alexa broods over my last response. It almost makes me forget that she is always listening to me.



Alexa also provides voice command access to other internet-enabled devices. Today I shall deal with  Echo and the LaMetric Time. LaMetric Time is a smart clock with internet radio. It features various apps including clock, radio, weather, sunrise/set times, moon phase, timers, stopwatch, message board, news update, etc. I dealt with all of the features of LaMetric in a previous post. Amazon echo can now be used as voice-control for LaMetric.


Once you are connected you can use your voice to tell Alexa to perform actions with the LaMetric time. For example:

"Alexa, tell LaMetric to start fifteen minute timer"

"Alexa, tell LaMetric to show clock"

"Alexa, tell LaMetric to wake me up at 7am"



Alexa, LaMetric and If This Then That

Both Alexa and LaMetric get even more interesting when you use the IFTTT app. IFTTT allows you to connect services together using 'applets', for example, if 'this' happens in one service, then 'that' happens in another. I use this service to pass notifications from my Android phone to the LaMetric device. In fact, at the last count I have several hundred IFTTT applets running various jobs in the background (including copying this blog post to Twitter, for example).

With these two applets running you can switch your internet radio off by simply leaving your house, place of work or hovel. When you come back again, the internet radio is ready for you. 

These applets provide you with buttons on your smart phone's home screen allowing you to control various parts of the LaMetric device at the touch of a button.

One of many applets for Alexa.
The Alexa App
Both the Alexa and LaMetric devices have apps for your Android device (sadly not Windows phone). These are required for access to various settings, such as clearing your shopping list, or cancelling alarms, but they also give you access to your device history.



The LaMetric app


Part of the LaMetric Time app showing just six of the apps you can get for it.

Quite apart from all of the awesome time apps that LaMetric Time can do for you, I mainly use my LaMetric for the internet radio. This app boasts over 3000 stations. Oh, and if you would prefer, you can use the LaMetric as a Bluetooth speaker for your phone.


Well that's it for now. More geeky tech stuff coming soon, or you may enjoy reading about that time I tried to use my BBC micro as my main computer, or when I had a virtual pet called Phil.

Analogue clock for python turtle

Today I discovered the turtle library for python.

If you are old enough to remember the educational programming language Logo, then you might remember spending hours in your school's BBC microcomputer lab playing with this electronic turtle.

Logo provides a way of drawing line graphics and patterns using simple commands such as 'forward' and 'right'. Logo is a good way of teaching and learning 'Computational Thinking' or the basics of programming. Today you can experience the same fun on your Raspberry Pi or Python interpreter on your PC, as the turtle library is included in the standard distribution.

After playing with a few random walks (which I may post at a later date), I had a go at creating a working analogue clock, and I am rather pleased with the results. Thanks to Sonny for his enthusiasm and suggested improvements.

Python 3 analogue clock using the turtle graphics library.



You can download the code, or copy it from below.

#Turtle Analogue Clock
#Tim Street
#version 1.6
#2017-06-23
#SHOWS GMT NOT BST

import turtle
import time

print("Python Turtle Analogue Clock")
print("By T Street")


#Deal with different time zones
ok = False
while not(ok):
print("\nFor example, for British summer time enter 1")
offset = int(input("Enter offset from GMT (-11 to 11) :"))
if offset >= -11 and offset <= 11:
ok = True

wn = turtle.Screen()
wn.title("TURTLE CLOCK")

SCALE = 1.7 # size of clock scale factor (try 2.0 to 0.5)

#create dial
mark = turtle.Turtle()
mark.speed(200)
mark.shape("circle")
for i in range(60):
      if i % 5 == 0:
            mark.pensize(10)
            mark.penup()
            mark.forward(200*SCALE)
            mark.pendown()
            mark.forward(10*SCALE)
            mark.penup()
            mark.backward(210*SCALE)
      else:
            mark.pensize(5)
            mark.penup()
            mark.forward(200*SCALE)
            mark.pendown()
            mark.forward(5*SCALE)
            mark.penup()
            mark.backward(205*SCALE)      
      mark.right(6)


update = True #controls whether minute and hour hand should update (once per minute)
updateSecond = True # controls whether the second hanbd should update
while True: 
      b = time.gmtime(time.time()) # current GMT
      m = b.tm_min # remember the current minute
      s = b.tm_sec # rember the current second
      if update:
            #hour hand
            hour = turtle.Turtle()
            hour.left(90)
            hour.speed(100*SCALE)
            hour.pensize(10)
            hour.shape("blank")
            hour.right(((b.tm_hour + offset) % 12) * 30 + b.tm_min * 0.5 )
            hour.backward(30*SCALE)
            hour.forward(160*SCALE)

            #minute hand
            minute = turtle.Turtle()
            minute.speed(100)
            minute.shape("blank")
            minute.left(90)
            minute.pensize(6)
            minute.right((b.tm_min) * 6)
            minute.backward(30*SCALE)
            minute.forward(180*SCALE)

            update = False
            
      if updateSecond:
            #second hand
            second = turtle.Turtle()
            second.speed(100)
            second.shape("blank")
            second.color("red")
            second.left(90)
            second.pensize(3)
            second.right((b.tm_sec) * 6)
            second.backward(30*SCALE)
            second.forward(190*SCALE)
            updateSecond = False

      time.sleep(0.3)
      b = time.gmtime(time.time())
      new_min = b.tm_min
      new_sec = b.tm_sec

      if new_min != m:
            update = True
            hour.clear() # Clear out the drawing (if any)
            hour.reset()
            minute.clear()
            minute.reset()
      if new_sec != s:
            updateSecond = True
            second.clear()
            second.reset()


Seasonal change for the day clock

Today was a lovely summery day in old Blighty.  It was good to generate some vitamin D, but I guess that was our summer over for another year.  If you blink then you miss it.

It reminded me that my day clock needed updating. The old autumnal leaves I posted originally back in December no longer seem appropriate. So today I added a rolling background image that changes with the seasons. There is a different image for each time of year: Spring, Summer, Autumn and Winter.

Do please check it out.

The old Autumnal version. Do click it to see what's new.

More groovy patterns for Raspberry Pi

Following on from the last post about groovy patterns for Raspberry Pi, I present my latest program, another random walk.

It is a random walk similar to last time, however with this one there are three degrees of freedom (rather than horizontal and vertical) and rather than a line, the object displayed in a coloured 3D box.
This code is for BASIC V running under RISCOS on the Raspberry Pi. Copy the code, or download directly.

The code:

   10 REM Blocks
   20 REM T Street
   30 REM 2017-05-21
   40 :
   50 MODE 19
   52 delay = 0
   55 colcyc = 0
   60 angle1 = RAD(45): angle2 = RAD(20)
   70 size = 16
   72 LIMIT = 50
   73 DENSITY = 40
   80 xo=500:yo=500
   90 x = xo: y=yo
  100 dir = RND(5)
  110 PROCsetdir
  112 lc = 0
  114 dc = 0
  120 REPEAT
  140   PROCbox(x,y,size,angle1,angle2)
  141   t=TIME:REPEAT UNTIL TIME>t+delay
  150   x = x + dx: y = y + dy
  151   lc = lc + 1
  160   IF RND(6) = 1 THEN PROCchangeDir
  170   IF x<0 OR x>1000 OR y<0 OR y>1000 OR lc>LIMIT THEN
  180     x=xo:y=yo
  181     colcyc = colcyc+2: IF colcyc > 127 colcyc = 0
  182     lc = 0
  183     dc = dc + 1
  190   ENDIF
  191   IF dc>DENSITY THEN
  192     dc = 0:CLS:x=xo:y=yo:lc = 0
  193   ENDIF
  200 UNTIL FALSE
  210 END
  220 :
  230 DEFPROCbox(x,y,s,ar,au)
  240 REM draws a box at coords x,y
  250 REM where the coords are the lower left corner
  260 REM and s is the size of box
  270 REM and ar and au are angles
  280 MOVE x,y
  290 LOCAL up, right
  300 up = s*SIN(au)
  310 right = s*COS(ar)
  320 REM front side
  330 GCOL 2+colcyc
  340 MOVE x,y+s
  350 PLOT 85,x+s,y
  360 MOVE x+s, y:MOVE x, y+s
  370 PLOT 85, x+s, y+s
  380 REM right hand side
  390 GCOL 1+colcyc
  400 MOVE x+s+right, y+up: MOVE x+s, y+s
  410 PLOT 85, x+s, y
  420 MOVE x+s+right, y+up: MOVE x+s, y+s
  430 PLOT 85, x+s+right, y+s+up
  440 REM top
  450 GCOL 1+colcyc
  460 MOVE x+right, y+s+up: MOVE x+s, y+s
  470 PLOT 85, x, y+s
  480 MOVE x+right, y+s+up: MOVE x+s, y+s
  490 PLOT 85, x+s+right, y+s+up
  491 GCOL 0
  492 MOVEx,y:DRAW x+s,y:DRAW x+s,y+s:DRAWx,y+s:DRAW x,y
  500 ENDPROC
  510 :
  520 DEFPROCsetdir
  530 CASE dir OF
  540   WHEN 1
  550   dx = 0: dy = size
  560   WHEN 2
  570   dx = size: dy = 0
  580   WHEN 3
  590   dx = 0: dy = -size
  600   WHEN 4
  610   dx = -size: dy = 0
  620   WHEN 5
  630   dx = -(size*COS(angle2)): dy = -(size*SIN(angle2))
  635   WHEN6
  636   dx = (size*COS(angle2)): dy = (size*SIN(angle2))
  640 ENDCASE
  650 ENDPROC
  660 :
  670 DEFPROCchangeDir
  680 dir=RND(6)
  690 PROCsetdir
  700 ENDPROC
  710 :


Weird things spotted in Whitby today

I went to Whitby today.

Whitby is a lovely town on the North East coast of England. Whitby is a place where you can be who you want to be. Whitby is home to the famous Lucky Duck; was the place where Count Dracula first arrived in England; and is home to the superdecade games chatbot - Mac.

You will see many strange things in Whitby. Today I saw some, and managed to get a few on camera.

Kleptoparasitism is a thing. This is how gulls feed. Just because you bought the chips doesn't mean that the seagull respects your property. I saw this gull trying to break into someone's car. When it realised that it couldn't peck through the roof, it decided to try and eat the aerial instead. Then it saw my chips and wanted some. It didn't get any. I am not sure why this fellow looks like it has a mustache, it just does.
There are many junk shops in Whitby. This one is selling a sarcophagus. The shop was closed, but there was a phone number to ring if you wanted to enquire about anything. I want to ask how much this costs, because, you know, you need somewhere to sleep at night.
Errr, what? I don't know what the actual flip this is. Moving on....

This shop selling LPs from some of the worst vermin of society.
Sorrrrrrrry
Taken from a poster by the authorities, encouraging us not to feed the vermin of the sea - the rats with wings, the aerial-munchers, the chip thieves. Is it just me, or does it look like that photograph of Theresa May? You know the one....
....Do NOT feed (or vote for unless you can afford to sell your house to pay for your health care).

Groovy patterns for Raspberry Pi

In a spare moment whilst I was waiting for some food to cook, I decided to play with the BASIC on the Raspberry Pi. I'm using the brilliant RISCOS for the Pi which comes with BASIC V and about a gigabyte of RAM.

I decided to create a 'random walk' in an attempt to create something that would look like an abstract map of a city. I am quite pleased with the results.

Pictures first, and then the code.

It's supposed to look sort of 3D, sort of.

It really pelts along on my Raspberry Pi
When the line wanders off the screen it starts again in the middle of the pattern with a slight offset and a new colour. Lines sometimes quit and start again (controlled by the variable LIMIT%, and after a while the pattern will refresh (controlled by the DENSITY% variable).

Here is the source code for RISCOS BASIC V, which will require only minor modification to run in BBC BASIC for Windows, or on a BBC Master.

Copy the code below, or download the file directly.

   10 REM Draws a 'city scape'
   20 REM T Street
   30 REM 2017-05-10
   40 MODE 19
   50 ONERROR IF ERR=17 OSCLI("*DESKTOP")
   60 colCycle%= 0
   70 GCOLRND(4)+colCycle%
   80 REPEAT
   90   refresh%=FALSE
   99   REM Origin
  100   xo = 500 :yo = 500
  109   REM start at origin
  110   x = xo :y = yo
  119   REM distance moved each step
  120   dx=0:dy=0
  130   m = 16
  139   REM counts number of steps
  140   c = 0
  150   l=0
  160   LIMIT% = 400
  170   DENSITY% = 32
  180   MOVE x,y
  190   REPEAT
  200     c=c+1:l=l+1
  210     x=x+dx
  220     y=y+dy
  230     DRAW x,y
  240     r = RND(4)
  250     IF r=1 dx = 0:dy=m
  260     IF r=2 dx = m:dy=0
  270     IF r=3 dx = 0:dy=-m
  280     IF r=4 dx = -m:dy=0
  290     IF x<0 OR x>1000 OR y<0 OR y>1000 OR c>LIMIT%  THEN
  300       xo = xo+2:yo=yo+2
  310       x=xo
  320       y=yo
  330       c=0
  340       MOVE x,y
  350       GCOLRND(4)+colCycle%
  360     ENDIF
  370     IF l>LIMIT%*DENSITY% THEN
  380       refresh% = TRUE
  390     ENDIF
  400   UNTIL refresh%
  410   colCycle% = colCycle% + 4: IF colCycle% > 128: colCycle% = 0
  420   CLS
  430 UNTIL FALSE


Remote desktop for Raspberry Pi

Avid readers of this blog will know that I am a big fan of the RISCOS pi operating system for Raspberry Pi. I mainly use it for the nostalgia factor, however I also keep a set of note on it in addition to some programming.

I also have a need for the Linux distribution as well.  I currently regularly use Raspbian flavour of Linux for the following tasks:

These are all jobs that I want to have running permanently, however it started to annoy me that I had to quit Raspbian in order for the device to boot into RISCOS.  The solution was to get a second Raspberry Pi 2 to use as a dedicated RISCOS Pi and leave the first device for uninterrupted Linux stuff! This caused it's own problems, of course, as I only have room for one monitor, one keyboard and one mouse. Swapping the devices over when I wanted to quickly check on something on the server was becoming irritating and so the obvious solution is to install a remote desktop.

If you were not aware, a remote desktop allows you to run one computer from another computer. You literally see the desktop of one computer in a window on a second machine. This is incredibly useful for doing things with Raspberry Pi wherever the use of keyboards, mice and monitors are a problem. For example, you might want to put the Raspberry Pi in a remote location in your house or garden to monitor temperature, or take photos as aliens pass over your roof. Maybe you want to set the machine up as a burglar detection and capture system. Maybe your Raspberry Pi is the central brain of your doomsday machine or robot butler and having a monitor and keyboard attached is just soooo nineteen nineties. Either way, controlling your Pi from another computer or tablet is really cool.

Your choice of software for performing a remote desktop depends on your current distribution of Raspbian: you could try xrdp, or VNC.

XRDP

I have used xrdp on a number of Pi devices at both work and at home. These instructions should work if your device was installed before 2017.


1. First install the xrdp software onto your Pi. Navigate to the terminal and type: sudo apt-get install xrdp
2. Follow any on-screen instructions.
3. Once completed restart your device with sudo restart
4. You will need the IP address of your device on your home network. If you don't know it you should be able to find it from either your home router's admin page, or type the command: ifconfig You are looking for a line that reads something like: inet addr:192.168.1.162

5. Once you are happy that xrdp is ready for your Raspberry Pi you should be able to connect from your second computer.  In Windows 10 select Cortana and type "Remote Desktop". This should launch a program called "Remote Desktop Connection".

Finding the Remote Desktop in Windows 10. For earlier versions of Windows, it will be found in your Start > All programs > Accessories folder.

6. Type in the IP address of your Raspberry Pi from part 4 (for example, mine is 192.168.1.162).
7. Enter your username and password. You should now find that you can now see your Raspberry Pi desktop.

Enter your username and password at the prompt. If you haven't changed them already, then your username should be 'pi' and the password is 'raspberry'

If you get connection problems, then you probably need to follow the steps for VNC below.

VNC

1. Navigate to your Terminal in Raspbian and type: sudo raspi-config
2. A menu should appear. Find “Interfacing Options” and make sure that VNC is enabled.
3. Reboot the Raspberry Pi.
4. Whilst your Pi is rebooting you can install the VNC Viewer client software on your second computer. I downloaded the portable version from the RealVNC website for Windows, however other versions are available for other machines.
5. Once you have this client running you should be able to enter your IP address and connect.

If everything has gone to plan then you should be seeing your Raspberry Pi desktop on your other computer. Very handy for controlling your computer from another room.

Another really good feature is that VNC will allow you to transfer files from your computer onto the Raspberry Pi. To do this, first click on the icon in the top left corner. Then select "File Transfer" from the menu. I use this to maintain various files on my home server. For example I have a set of notes written using Zim. These notes are written on my PC and keep track of various things that are useful for both RISCOS and Raspbian (such as all the instructions on this blog article). As soon as I learn something new about the Raspberry Pi, I make a note of how I did it and then upload it to the server. As they are kept on my server I can access them from any of the machines on my home network, including the RISCOS device. Very handy indeed!




Today we celebrate two years in space

On the first of May two years ago we launched Project Poxima the world's first internet based space mission.

Project Proxima is a hypothetical, light-speed space mission to the Proxima Centauri star system. The aim is to create a teaching tool that helps explain the vastness of interstellar space (it's big).

Today Proxima has traveled nearly 19 trillion km - that's about 47% of the today distance.


A lot has happened in the time since launch: perhaps most notably are the rise of Trump and the British referendum on Brexit. Most interestingly, however, that since launching the Project Proxima mission, scientists have discovered an earth-like planet in orbit around the Proxima Centauri system.

You can get involved in the mission by following on Twitter, or tracking the progress on the website.

You can also become an official supporter and sign up for email alerts.


Want to read more about Project Proxima?

Castle Defender is a brilliant new game for the BBC micro

Every now and then a new game is developed for vintage computers. Built by computing enthusiasts these games are often better than the original offerings from the time that the machines were first popular, or include titles and ideas that come from the modern age.

Castle Defender is the BBC micro's first ever tower defence game, and it is really very good. Programmed by Chris Bradburne with graphics by John Blythe, this game is superbly well written and designed. The graphics are stunning and the game play is addictive. I have been playing all morning, with admittedly, a pathetic high score of only 40% to show for my efforts.

A hoard of orcs and goblins storm my castle defences on the BeebEm emulator.
The aim of Castle Defender is to protect your castle from the waves of computer controlled 'nasties'. You build towers at strategic points along the way to shoot your enemies to death. There are three different types of weapons which can be upgraded as you earn more gold. Indeed, upgrading your weapons is the only way you will succeed at this game.

There is an initial steep learning curve in Castle Defender. At first the cursor key controls seem a little counter-intuitive, and you will possibly long for a touch screen. The best approach is to only use the left and right cursor keys to navigate the battle field. The second lesson you will need to learn is how to read the display at the bottom of the screen. Some enemies have shields which make them almost impossible to kill unless you have weapons that can deal with shields. Choosing the appropriate mix of weapons is essential to surviving each wave of nasties in Castle Defender.

Snakes! I hate snakes, Jock! I hate 'em! Come on! Show a little backbone, will ya!
There are four levels of superb high-resolution MODE 1 graphics, with each level getting progressively more 'evil'. You can skip levels by pressing the corresponding key 2,3 or 4 at the start of the game, although if you do the game wont track your high score. The animation is very smooth and the enemies make a satisfying 'pop' when they die.

It really is a joy to see developers creating new games for vintage machines, particularly when the results are such superb quality releases. One geek experience point is awarded each to Chris Bradburne and John Blythe.

You can download a copy of this game for your BBC micro or BBC master computer, or run it on your PC in an emulator such as BeebEm.

Zap that nasty! The loading screen of Castle Defender.
More modern games for vintage computers are available on the Homebrew Heroes Facebook page.

Well that's all from me today. I'm off to squish some 8-bit orcs...


Some weather apps

Yesterday's post started out about the Raspberry Pi Sense Hat, and ended up looking at the Barometer app for Lumia 950. Today, I'll look at a couple more useful weather apps for your Lumia 950.

Thermometer
I have been using GPS Thermometer Free from Jappi-Soft. This app uses your current location at matches it with publicly available weather station data to show the outside temperature for your location.

GPS Thermometer Free on Lumia 950
The paid version includes a live tile with adverts removed. Both versions include a choice of accent colours and displays. Bizarrely, several people in the comments section of the app were disappointed because the app doesn't display the inside temperature of their homes. These people have clearly misunderstood how this app works. I will reiterate: It finds the nearest weather station to you and displays the temperature as measured by that weather station on your screen.

Sun and Moon
I love this app. Sun & Moon by Ronca is a simple app that gives a representation of where the sun and moon are currently located in their daily cycles.

Sun and moon on Lumia 950 showing the current position of the sun as though you were facing South on a cloudless day.

It also shows the sun rise and sunset times and the expected hours of sunlight. Sadly, the app does not cope with the annoying habit we Brits have of setting our clocks forward one hour in summer, so you you also need to add one hour onto the times displayed onscreen.

Perfect Weather
This is one of the most beautiful weather apps I have seen for Windows 10. Perfect Weather is a universal app, which means it is available for both your phone and PC, or any other device running Windows 10. It defaults to your current location, however you can set it other locations as well. Your display will show the current weather conditions, temperature, wind speed and direction, sun rise and set times, air pressure, moon phase, moon rise and set times. In effect it does everything the other two apps do plus more. Sliding your finger across the display will show an animation of the weather for that day. If you want to pay for the full version you will get a choice of background themes which include a Star Wars theme, presumably so you can see what the weather is like onTatooine  (presumably hot during the day, and cold at night).

Perfect Weather Universal showing the weather in Fantasia after The Nothing had finished doing its work.
Part of my Lumia 950 homescreen in all its Windows 10 goodness.

Is there a difference in air pressure between your head and toes?

It has been a lovely day in England today, with highs of 20 degrees (that's 68 F) and a gentle breeze. It has been the sort of weather for relaxing in the sun with a cool drink and a sun hat, and maybe a good book, because it is not often we get the chance to produce some vitamin D in this country. But I couldn't just sit around all day. During the peak of the midday sun, I retreated to the relative safety and coolness of my geek cave and tinkered with my Raspberry Pi Sense Hat data logger.

The 8-by-8 LED matrix on the Sense Hat, which is useful for anything your imagination can conceive. 

The Raspberry Pi Sense Hat data logger uses the brilliant Sense Hat to log temperature, pressure and humidity from its many sensors. You can grab my code from the link above, or read about other Sense Hat projects, and if you have a Raspberry Pi then this is an brilliant add on device that will guarantee hours of fun.


It was this tinkering that made me ponder the question raised in the title of this post.

Is there a difference in air pressure between your head and toes?
Assuming that you have toes on the ends of your feet (as I do), and not growing out of your forehead (as I don't), then there should be a difference in air pressure between these two points due to the difference in height between them (assuming that you are standing vertically). More to the point I wondered whether it was possible to measure this difference. Sadly, Raspberry Pi is not maneuverable enough to lift off my desk (so many things plugged in) which led me to look for barometer apps in the app store.

I soon found Barometr by SeNSSoft for my Lumia 950.

Air pressure at ground level

Air pressure at head height.
And there you have it. The answer is 'Yes', about 0.2 hecopascal (or about 0.1 hecopascal if your name is Frodo).

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