6/16/2022
JS Binary Decoder

software

I have recently been dealing with parsing binary data packets from various sources, and have published two NPM libraries from it - binary-decoder and sbd-direct-ip. How's how they came to be.
4/19/2022
New Zealand Low Power Wide Area Networks

electronics software

I have started experimenting with low power wide area networks (LP-WAN) in New Zealand using a u-blox SARA-R410-02B. Here is is what I have experimented with so far.
2/7/2022
Starting with ESP32

esp32 electronics software trap-watch

I started developing my trap-watch project on an ESP32-CAM using the ESP IDF. Here is the newbie difficulties I ran into.
2/4/2022
VIM Window Rabbit Hole

linux

Developing ESP-IDF components I thought it would be great if I could make a command to open all the files for a component at once. What a rabbit hole it was. Here is how I did it.
1/28/2022
Parsing Arguments in Bash

linux

Making a script parse arugments in Bash took me way too long last time I did it, so here is a nice full example of how to do it using getopt
1/8/2022
Where's my bait gone?

electronics conservation trap-watch

I have recently started trapping some introduced predators around my local area and have had baits and pre-feed disappear with nothing to show for it, so I decided to get sparky and see if I could catch the culprit in the act.

3/26/2021

Bathymetric Contours

Finally got around to creating a SLD style for GeoServer to display bathymetric contour lines using the GEBCO gridded bathymetric data. Here's how.

Getting slightly distracted, I noticed bathymetric contour layer we are using for our app doesn't cover one of the areas we are working in.

I had already downloaded the GEBCO gridded bathymetric data data for creating terrain tiles to use with CesiumJS and imported the TIFF into GeoServer, so I just needed to create the Style to display contours.

I started off with the very helpful GeoSever docs() on Rendering Transformations, namely the Contour extraction example. After adjusting the Transformation level values to more useful values for us, I tried previewing the map. Lots of lines!

Style preview showing all the contour lines

I needed to cut down the data shown on the map for the lower (more zoomed out) levels, so looked into rules and filters and added up two additional <Rule> sections with various levels of.

The rules produces the following previews

Style preview showing the very high-level contours on the globe

Style preview showing medium level contours around Oceania

Style preview showing full detail contours along the bottom of the North Island and New Zealand

Below is the style XML. I still need to figure out how to remove the lines produced from the edge of the TIFF image.


<?xml version="1.0" encoding="ISO-8859-1"?>
<StyledLayerDescriptor version="1.0.0"
  xsi:schemaLocation="http://www.opengis.net/sld StyledLayerDescriptor.xsd"
  xmlns="http://www.opengis.net/sld"
  xmlns:ogc="http://www.opengis.net/ogc"
  xmlns:xlink="http://www.w3.org/1999/xlink"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <NamedLayer>
    <Name>contour_dem</Name>
    <UserStyle>
      <Title>Bathymetry Contours</Title>
      <Abstract>Bathymetry contours produced from the GEBCO 15 arc-second gridded bathymetry</Abstract>
      <FeatureTypeStyle>
        <Transformation>
          <ogc:Function name="ras:Contour">
            <ogc:Function name="parameter">
              <ogc:Literal>data</ogc:Literal>
            </ogc:Function>
            <ogc:Function name="parameter">
              <ogc:Literal>levels</ogc:Literal>
              <ogc:Literal>0</ogc:Literal>
              <ogc:Literal>-100</ogc:Literal>
              <ogc:Literal>-200</ogc:Literal>
              <ogc:Literal>-300</ogc:Literal>
              <ogc:Literal>-400</ogc:Literal>
              <ogc:Literal>-500</ogc:Literal>
              <ogc:Literal>-600</ogc:Literal>
              <ogc:Literal>-700</ogc:Literal>
              <ogc:Literal>-800</ogc:Literal>
              <ogc:Literal>-900</ogc:Literal>
              <ogc:Literal>-1000</ogc:Literal>
              <ogc:Literal>-1100</ogc:Literal>
              <ogc:Literal>-1200</ogc:Literal>
              <ogc:Literal>-1300</ogc:Literal>
              <ogc:Literal>-1400</ogc:Literal>
              <ogc:Literal>-1500</ogc:Literal>
              <ogc:Literal>-1600</ogc:Literal>
              <ogc:Literal>-1700</ogc:Literal>
              <ogc:Literal>-1800</ogc:Literal>
              <ogc:Literal>-1900</ogc:Literal>
              <ogc:Literal>-2000</ogc:Literal>
              <ogc:Literal>-3000</ogc:Literal>
              <ogc:Literal>-4000</ogc:Literal>
              <ogc:Literal>-5000</ogc:Literal>
              <ogc:Literal>-6000</ogc:Literal>
              <ogc:Literal>-7000</ogc:Literal>
              <ogc:Literal>-8000</ogc:Literal>
              <ogc:Literal>-9000</ogc:Literal>
              <ogc:Literal>-10000</ogc:Literal>
              <ogc:Literal>-11000</ogc:Literal>
              <ogc:Literal>-12000</ogc:Literal>
            </ogc:Function>
          </ogc:Function>
        </Transformation>
        <Rule>
          <Name>deep_water</Name>
          <Title>Deep Water Contours</Title>
          <MaxScaleDenominator>800000</MaxScaleDenominator>
          <LineSymbolizer>
            <Stroke>
              <CssParameter name="stroke">#000000</CssParameter>
              <CssParameter name="stroke-width">1</CssParameter>
            </Stroke>
          </LineSymbolizer>
          <TextSymbolizer>
            <Label>
              <ogc:PropertyName>value</ogc:PropertyName>
            </Label>
            <Font>
              <CssParameter name="font-family">Arial</CssParameter>
              <CssParameter name="font-style">Normal</CssParameter>
              <CssParameter name="font-size">10</CssParameter>
            </Font>
            <LabelPlacement>
              <LinePlacement/>
            </LabelPlacement>
            <Halo>
              <Radius>
                <ogc:Literal>2</ogc:Literal>
              </Radius>
              <Fill>
                <CssParameter name="fill">#FFFFFF</CssParameter>
                <CssParameter name="fill-opacity">0.6</CssParameter>
              </Fill>
            </Halo>
            <Fill>
              <CssParameter name="fill">#000000</CssParameter>
            </Fill>
            <Priority>2000</Priority>
            <VendorOption name="followLine">true</VendorOption>
            <VendorOption name="repeat">100</VendorOption>
            <VendorOption name="maxDisplacement">50</VendorOption>
            <VendorOption name="maxAngleDelta">30</VendorOption>
          </TextSymbolizer>
        </Rule>
        <Rule>
          <Name>platform_limits</Name>
          <Title>Platform Limit Contours</Title>
          <MaxScaleDenominator>20000000</MaxScaleDenominator>
          <ogc:Filter>
            <ogc:Or>
              <ogc:PropertyIsEqualTo>
                <ogc:PropertyName>value</ogc:PropertyName>
                <ogc:Literal>-100</ogc:Literal>
              </ogc:PropertyIsEqualTo>
              <ogc:PropertyIsEqualTo>
                <ogc:PropertyName>value</ogc:PropertyName>
                <ogc:Literal>-500</ogc:Literal>
              </ogc:PropertyIsEqualTo>
              <ogc:PropertyIsEqualTo>
                <ogc:PropertyName>value</ogc:PropertyName>
                <ogc:Literal>-1000</ogc:Literal>
              </ogc:PropertyIsEqualTo>
              <ogc:PropertyIsEqualTo>
                <ogc:PropertyName>value</ogc:PropertyName>
                <ogc:Literal>-1500</ogc:Literal>
              </ogc:PropertyIsEqualTo>
              <ogc:PropertyIsEqualTo>
                <ogc:PropertyName>value</ogc:PropertyName>
                <ogc:Literal>-6000</ogc:Literal>
              </ogc:PropertyIsEqualTo>
            </ogc:Or>
          </ogc:Filter>
          <LineSymbolizer>
            <Stroke>
              <CssParameter name="stroke">#000000</CssParameter>
              <CssParameter name="stroke-width">1</CssParameter>
            </Stroke>
          </LineSymbolizer>
          <TextSymbolizer>
            <Label>
              <ogc:PropertyName>value</ogc:PropertyName>
            </Label>
            <Font>
              <CssParameter name="font-family">Arial</CssParameter>
              <CssParameter name="font-style">Normal</CssParameter>
              <CssParameter name="font-size">10</CssParameter>
            </Font>
            <LabelPlacement>
              <LinePlacement/>
            </LabelPlacement>
            <Halo>
              <Radius>
                <ogc:Literal>2</ogc:Literal>
              </Radius>
              <Fill>
                <CssParameter name="fill">#FFFFFF</CssParameter>
                <CssParameter name="fill-opacity">0.6</CssParameter>
              </Fill>
            </Halo>
            <Fill>
              <CssParameter name="fill">#000000</CssParameter>
            </Fill>
            <Priority>2000</Priority>
            <VendorOption name="followLine">true</VendorOption>
            <VendorOption name="repeat">100</VendorOption>
            <VendorOption name="maxDisplacement">50</VendorOption>
            <VendorOption name="maxAngleDelta">30</VendorOption>
          </TextSymbolizer>
        </Rule>
        <Rule>
          <Name>full</Name>
          <Title>Full Detail Contours</Title>
          <ogc:Filter>
            <ogc:Or>
              <ogc:PropertyIsEqualTo>
                <ogc:PropertyName>value</ogc:PropertyName>
                <ogc:Literal>-1000</ogc:Literal>
              </ogc:PropertyIsEqualTo>
              <ogc:PropertyIsEqualTo>
                <ogc:PropertyName>value</ogc:PropertyName>
                <ogc:Literal>-6000</ogc:Literal>
              </ogc:PropertyIsEqualTo>
            </ogc:Or>
          </ogc:Filter>
          <LineSymbolizer>
            <Stroke>
              <CssParameter name="stroke">#000000</CssParameter>
              <CssParameter name="stroke-width">1</CssParameter>
            </Stroke>
          </LineSymbolizer>
          <TextSymbolizer>
            <Label>
              <ogc:PropertyName>value</ogc:PropertyName>
            </Label>
            <Font>
              <CssParameter name="font-family">Arial</CssParameter>
              <CssParameter name="font-style">Normal</CssParameter>
              <CssParameter name="font-size">10</CssParameter>
            </Font>
            <LabelPlacement>
              <LinePlacement/>
            </LabelPlacement>
            <Halo>
              <Radius>
                <ogc:Literal>2</ogc:Literal>
              </Radius>
              <Fill>
                <CssParameter name="fill">#FFFFFF</CssParameter>
                <CssParameter name="fill-opacity">0.6</CssParameter>
              </Fill>
            </Halo>
            <Fill>
              <CssParameter name="fill">#000000</CssParameter>
            </Fill>
            <Priority>2000</Priority>
            <VendorOption name="followLine">true</VendorOption>
            <VendorOption name="repeat">100</VendorOption>
            <VendorOption name="maxDisplacement">50</VendorOption>
            <VendorOption name="maxAngleDelta">30</VendorOption>
          </TextSymbolizer>
        </Rule>
      </FeatureTypeStyle>
    </UserStyle>
  </NamedLayer>
</StyledLayerDescriptor>

2/25/2021
shm That Cache

yarn docker development

I am often trying to find more space on my hard drives and found today my own docker containers wasting space thanks to ! Here's how I fixed it.
2/2/2021
Blob blob blob blob Stayin' Alive Stayin' Alive

software javascript debugging memory

Upon recently trying Deezer again, I found their web app ate all my memory when running in Firefox, so I decided to see if I could find out why. I got as far as memory-file-data/string and Blobs. Here's how.
12/25/2020
A new Litter Survey

software litter litter-survey

In a culmination of litter surveys and litter picks, linked data and data exploration, and remoteStorage and ActivityPub, I have created a web-based litter pick/survey app that I hope will allow federated citizen science.
12/13/2020
Hoe Stream Trash

litter pi-trash-cam litter-pick

My latest litter pick target was Hoe Stream and the White Rose Lane Local Nature Reserve. Here's how it went.
11/24/2020
Release the Beast

software gitlab ci release

I just created a Gitlab CI job to create a release with information from a CHANGELOG.md file for some of my projects. Here's how I did it.
9/30/2020
Gitlab CI Caching

gitlab continuous integration

I noticed something strange happening during build process during a multi-tasking bug fix. Turns out I was using Gitlab CI's caching incorrectly. I should have been using artifacts. Here's what I saw.
9/21/2020
Birthday Trash

litter pi-trash-cam

As a birthday treat, I took the day off work to try out my electronerised litter picker. Here's how it went.
9/13/2020
Pi Trash Cam

raspberry pi electronics litter pi-trash-cam

In preparation for a day of litter picking, I finally got round to a project idea - attaching a camera to a litter picker to record it all. Here's what I did.
8/25/2020
yarn add --dev webdriverio

first-draft software testing gitlab

I finally started implementing UI testing on first-draft using WebdriverIO. While writing tests was easy, getting the tests running was a little more difficult. Here is how I did it.
8/16/2020
Hooray! My new blog is live! Based on Sapper, using MongoDB and eventually ActivityPub and ActivityStreams, it will be my federated posting hub to the world.

software blog
8/9/2020
Removing EXIF Data from Photos

exif photos

Creating this new blog, I wanted to make sure there was no metadata data leaking personal information. Here's how I removed all the metadata tags except the ones I wanted from my photos.
8/9/2020
tmux List and Reattach

tmux bash software

Using tmux for your terminal multiplexer but want an easy to reattach to a session? Here's a small bash script to do it.
8/8/2020
Selectable Shell Examples

markdown syntax css

Here's how to help your readers save time by making your post's shell commands easy to select and copy - with a simple CSS property.
8/5/2020
Be Dates You

mongodb docker

Making my new blog, I didn't initially set the published dates to be native dates in the database. Here what I did to change them ...and do all the upgrades I needed.
7/8/2020
Testing vue components

software vue testing javascript

I recently needed to test that some Vue components were creating the correct HTML. To do this, I decided to create snapshots of Object representations of the rendered HTML.
2/20/2019
No More Numbers

javascript html5 software

HTML5 number inputs aren't useful, but tel inputs, have all the power
12/21/2018
A Hacker "Hacked" Me

security email grep

I decided to look into the extortion emails I have been getting and wrote a small script to extract the bitcoin addresses that have been used.
12/7/2018
Mouse Surgery

pledge to not upgrade electronics

As part of my pledge not to upgrade, I decided to repair two of my failing mice instead of replacing them with a brand new model (as tempting as it was). Here's what I did.
10/29/2018
Danger Danger, Highly Reactive

vue reactive graphing data
9/11/2018
Switching to SSR

react ssr react-loader
8/10/2018
Clean Docker Registry

node docker console javascript
2/1/2018
Testing on the Filesystem

testing javascript
1/26/2018
Tag You Are

javascript tags
1/25/2018
NaN Got Me

rubber duck save javascript nodejs json
4/28/2017
All our app's tabs are belong to us

angular javascript localstorage rxjs sessionstorage
2/20/2016
Developing NPM modules

nodejs npm
2/20/2016
Nfa + Nfb or N(f+fa+fb)

array function javascript jsperf
10/31/2015
Photo Layout

arranger css gallery hierarchy html javascript photos tinymce wordpress software
10/31/2015
Browning Pass HideAway Web Site

css gallery hierarchy html wordpress
10/17/2015
Think Mobile

mobile web
10/13/2015
Pledge to Refuse and Not Buy Bottled Water

environment pledges
2/25/2015
Run PHP run!

maximum execution time php trial and error
11/26/2014
Gallery Hierarchy

gallery hierarchy photos
10/3/2014
Vim and functions

function navigation tags vim
9/26/2014
I'm making hierarchies

hierarchical data hierarchy php
9/4/2014
Google Sheets fun

google google script google sheets javascript sheets
8/13/2014
Travel Photos

photo management photos travel photos
8/13/2014
Image managment scripts

photo management photos
7/31/2014
MeldCE logo

css html5 javascript svg
4/26/2014
MoltenDB

database moltendb mongodb nodejs
10/29/2013
The Expensive Side

house
9/22/2013
abcde

music
7/16/2013
Energizer Power Plus Rechargeable Batteries

gadgets
3/4/2013
USAR FOGTeX

fogtex
2/21/2013
Personal Gear Bag

rescue gear
2/18/2013
Geocaching Stamp

stamp geocaching
4/2/2007
Call Record Presenter

parser python sqlite web
9/25/2004
Kimi Ora School

css html
6/25/2004
All About Catering Web Site

css html
7/26/2003
Quantum Accounting Web Site

css html