Comments

• 

  6 months ago by moio | Reply

  Day 1 diary - the physical prototyping day

  Spent a bit of time into producing good SVGs with Python, then printed them and tried to find dimensions that worked (one big and one small for testing).

  After few iterations decided to go with octagonal stars rather than plain octagons:

  

  Then literally hammered out holes with a 10mm punch! Worked beautifully.

  

  Then, cut and tested positioning of filter film:

  

  All seems good from the physical realm so far.

  Next up: coding to determine per-hole filter positioning!

×
Edit Comment 7454
# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

* Use asterisks
* for lists

This is an [example link](http://example.com/)

This is an ![example image](http://paste.opensuse.org/view/raw/68957446)

This is a user link @hans

This is a project link hw#some-cool-title
More Complex Markdown Help
Formatting Help
• Edit
• Preview
# Day 1 diary - the physical prototyping day Spent a bit of time into producing good SVGs with Python, then printed them and tried to find dimensions that worked (one big and one small for testing). **After few iterations decided to go with octagonal stars rather than plain octagons:**  **Then literally hammered out holes with a 10mm punch! Worked beautifully.**  **Then, cut and tested positioning of filter film:**  All seems good from the physical realm so far. Next up: coding to determine per-hole filter positioning!
 
×
Reply to moio
Day 1 diary - the physical prototyping day
Spent a bit of time into producing good SVGs with Python, then printed them and tried to find dimensions that worked (one big and one small for testing).
After few iterations decided to go with octagonal stars rather than plain octagons:

Then literally hammered out holes with a 10mm punch! Worked beautifully.

Then, cut and tested positioning of filter film:

All seems good from the physical realm so far.
Next up: coding to determine per-hole filter positioning!
---
# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

* Use asterisks
* for lists

This is an [example link](http://example.com/)

This is an ![example image](http://paste.opensuse.org/view/raw/68957446)

This is a user link @hans

This is a project link hw#some-cool-title
More Complex Markdown Help
Formatting Help
• Edit
• Preview
 
• 

  6 months ago by moio | Reply

  Day 2 diary: mostly coding

  CP-SAT

  Learnt a lot about CP-SAT, evolved some code I had around to handle:

  • a variable number of "pizzas" ("stars with filter windows")
  • a variable number of "slices" ("sectors" of stars)
  • a variable number of "windows" per "slice"
  • a variable number of "angles" filters can be glued on
  • a variable number of "images"

  Difficult part today is the reordering of "pizzas" in the "pizza stack". Giving that ability makes more combinations possible, but indirection has to be dealt with in code.

  Testing

  The good part about this problem is that tests can trivially be randomized, so it's easy to see if produced solutions work or not.

  The bad part is not all randomized problem instances have a solutions. For those who do not, CP-SAT will happily burn CPUs for hours. I added a pretty arbitrary time limit.

  ChatGPT

  I used ChatGPT for the scaffolding work - and was quite happy with it:

  Set up a new Python 3.9 based project according to current best practices.

  The project must use the ortools library from Google (note that is a wrapper around a C++ library)

  Include support for: linting, dependency management, github codespace, tests, a Dockerfile, github actions on push and PR including and tests and lint, github actions for release of source archive and docker container on ghcr.io

  Also include a scaffolded README and LICENSE (AGPL)

  The project must compile and work cross platform, including Linux x86 and Mac arm.

  Explain every file created step by step and why

  Not a perfect result, but a good result to learn from - faster than stitching together 10 blog posts (for someone not daily into an ecosystem).

×
Edit Comment 7526
# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

* Use asterisks
* for lists

This is an [example link](http://example.com/)

This is an ![example image](http://paste.opensuse.org/view/raw/68957446)

This is a user link @hans

This is a project link hw#some-cool-title
More Complex Markdown Help
Formatting Help
• Edit
• Preview
# Day 2 diary: mostly coding ## CP-SAT Learnt a lot about CP-SAT, evolved some code I had around to handle: - a variable number of "pizzas" ("stars with filter windows") - a variable number of "slices" ("sectors" of stars) - a variable number of "windows" per "slice" - a variable number of "angles" filters can be glued on - a variable number of "images" Difficult part today is the reordering of "pizzas" in the "pizza stack". Giving that ability makes more combinations possible, but indirection has to be dealt with in code. ## Testing The good part about this problem is that tests can trivially be randomized, so it's easy to see if produced solutions work or not. The bad part is not all randomized problem instances have a solutions. For those who do not, CP-SAT will happily burn CPUs for hours. I added a pretty arbitrary time limit. ## ChatGPT I used [ChatGPT](https://chat.openai.com) for the scaffolding work - and was quite happy with it: > Set up a new Python 3.9 based project according to current best practices. > > The project must use the ortools library from Google (note that is a wrapper around a C++ library) > > Include support for: linting, dependency management, github codespace, tests, a Dockerfile, github actions on push and PR including and tests and lint, github actions for release of source archive and docker container on ghcr.io > > Also include a scaffolded README and LICENSE (AGPL) > > The project must compile and work cross platform, including Linux x86 and Mac arm. > > Explain every file created step by step and why Not a perfect result, but a good result to learn from - faster than stitching together 10 blog posts (for someone not daily into an ecosystem). :+1:
 
×
Reply to moio
Day 2 diary: mostly coding
CP-SAT
Learnt a lot about CP-SAT, evolved some code I had around to handle:
• a variable number of "pizzas" ("stars with filter windows")
• a variable number of "slices" ("sectors" of stars)
• a variable number of "windows" per "slice"
• a variable number of "angles" filters can be glued on
• a variable number of "images"
Difficult part today is the reordering of "pizzas" in the "pizza stack". Giving that ability makes more combinations possible, but indirection has to be dealt with in code.
Testing
The good part about this problem is that tests can trivially be randomized, so it's easy to see if produced solutions work or not.
The bad part is not all randomized problem instances have a solutions. For those who do not, CP-SAT will happily burn CPUs for hours. I added a pretty arbitrary time limit.
ChatGPT
I used ChatGPT for the scaffolding work - and was quite happy with it:
Set up a new Python 3.9 based project according to current best practices.
The project must use the ortools library from Google (note that is a wrapper around a C++ library)
Include support for: linting, dependency management, github codespace, tests, a Dockerfile, github actions on push and PR including and tests and lint, github actions for release of source archive and docker container on ghcr.io
Also include a scaffolded README and LICENSE (AGPL)
The project must compile and work cross platform, including Linux x86 and Mac arm.
Explain every file created step by step and why
Not a perfect result, but a good result to learn from - faster than stitching together 10 blog posts (for someone not daily into an ecosystem).
---
# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

* Use asterisks
* for lists

This is an [example link](http://example.com/)

This is an ![example image](http://paste.opensuse.org/view/raw/68957446)

This is a user link @hans

This is a project link hw#some-cool-title
More Complex Markdown Help
Formatting Help
• Edit
• Preview
 
• 

  6 months ago by moio | Reply

  Day 3 diary: 3 failures, 1 success

  Failure 1: adding the possibility of re-ordering the stack

  I thought that allowing to re-ordering pizzas in the stack could help with storing more "images" - found out that as not the case. On a large set of pseudorandom tests, only an extra 4 out of 186 could be solved by changing the order. Not worth it, commit reverted.

  Failure 2: going from a SAT problem to an optimization problem

  CP-SAT has the cool ability of allowing to specify an objective function to minimize or maximise - making it simple to reformulate a satisfiability problem in an optimization one. I tried this approach to make the assignments more flexible but failed: I could not find a good way to mix it with the Automaton constraints which I am using to simulate light traveling through a series of filters. Path abandoned for now.

  Failure 3: allowing brighter-than-specified pixels

  This seemed an easy way to enlarge the solution space - interestingly, almost no effect was visible in tests. Sticking for the simpler approach (to match pixel values exactly) for now.

  Success! First small four-pizza prototype works!

  I am happy to report that after some serious hammering and cutting...

  

  ...and serious gluing of filter films...

  

  ...I've got a nice filter set! Notice how filtering of monitor light (which is polarized) changes with rotation!

  

  Now I made four pizzas...

  

  And, in the right order, they will display a programmed X pattern!

  

  I was able to "store" 7 patterns in the four pizzas (a "Y", a "q", the "X" above, an "o", an "I", a "c" and a "K").

  Next step: the bigger brother pizza with bigger patterns!

×
Edit Comment 7604
# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

* Use asterisks
* for lists

This is an [example link](http://example.com/)

This is an ![example image](http://paste.opensuse.org/view/raw/68957446)

This is a user link @hans

This is a project link hw#some-cool-title
More Complex Markdown Help
Formatting Help
• Edit
• Preview
# Day 3 diary: 3 failures, 1 success ## Failure 1: adding the possibility of re-ordering the stack I thought that allowing to re-ordering pizzas in the stack could help with storing more "images" - found out that as not the case. On a large set of pseudorandom tests, only an extra 4 out of 186 could be solved by changing the order. Not worth it, commit reverted. ## Failure 2: going from a SAT problem to an optimization problem CP-SAT has the cool ability of allowing to specify an objective function to minimize or [maximise](https://developers.google.com/optimization/reference/python/sat/python/cp_model#maximize) - making it simple to reformulate a satisfiability problem in an optimization one. I tried this approach to make the assignments more flexible but failed: I could not find a good way to mix it with the [Automaton constraints](https://developers.google.com/optimization/reference/python/sat/python/cp_model#addautomaton) which I am using to simulate light traveling through a series of filters. Path abandoned for now. ## Failure 3: allowing brighter-than-specified pixels This seemed an easy way to enlarge the solution space - interestingly, almost no effect was visible in tests. Sticking for the simpler approach (to match pixel values exactly) for now. ## Success! First small four-pizza prototype works! I am happy to report that after some serious hammering and cutting...  ...and serious gluing of filter films...  ...I've got a nice filter set! Notice how filtering of monitor light (which is polarized) changes with rotation!  Now I made four pizzas...  And, in the right order, they will display a programmed X pattern!  I was able to "store" 7 patterns in the four pizzas (a "Y", a "q", the "X" above, an "o", an "I", a "c" and a "K"). Next step: the bigger brother pizza with bigger patterns!
 
×
Reply to moio
Day 3 diary: 3 failures, 1 success
Failure 1: adding the possibility of re-ordering the stack
I thought that allowing to re-ordering pizzas in the stack could help with storing more "images" - found out that as not the case. On a large set of pseudorandom tests, only an extra 4 out of 186 could be solved by changing the order. Not worth it, commit reverted.
Failure 2: going from a SAT problem to an optimization problem
CP-SAT has the cool ability of allowing to specify an objective function to minimize or maximise - making it simple to reformulate a satisfiability problem in an optimization one. I tried this approach to make the assignments more flexible but failed: I could not find a good way to mix it with the Automaton constraints which I am using to simulate light traveling through a series of filters. Path abandoned for now.
Failure 3: allowing brighter-than-specified pixels
This seemed an easy way to enlarge the solution space - interestingly, almost no effect was visible in tests. Sticking for the simpler approach (to match pixel values exactly) for now.
Success! First small four-pizza prototype works!
I am happy to report that after some serious hammering and cutting...

...and serious gluing of filter films...

...I've got a nice filter set! Notice how filtering of monitor light (which is polarized) changes with rotation!

Now I made four pizzas...

And, in the right order, they will display a programmed X pattern!

I was able to "store" 7 patterns in the four pizzas (a "Y", a "q", the "X" above, an "o", an "I", a "c" and a "K").
Next step: the bigger brother pizza with bigger patterns!
---
# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

* Use asterisks
* for lists

This is an [example link](http://example.com/)

This is an ![example image](http://paste.opensuse.org/view/raw/68957446)

This is a user link @hans

This is a project link hw#some-cool-title
More Complex Markdown Help
Formatting Help
• Edit
• Preview
 
• 

  6 months ago by moio | Reply

  Day 4 diary: scale up!

  Today I dealt with the bigger version of the puzzle. Software scaled just fine!

  About hardware I was lucky enough to get help from my son across all phases!

  

  I am really happy with the result, here they are in all their whiteness:

  

  What message did we hid in there? Stay tuned tomorrow for the last demo!

  PS. Thanks to colleague AR about having kids do some of the job - that worked great!

×
Edit Comment 7640
# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

* Use asterisks
* for lists

This is an [example link](http://example.com/)

This is an ![example image](http://paste.opensuse.org/view/raw/68957446)

This is a user link @hans

This is a project link hw#some-cool-title
More Complex Markdown Help
Formatting Help
• Edit
• Preview
# Day 4 diary: scale up! Today I dealt with the bigger version of the puzzle. Software scaled just fine! About hardware I was lucky enough to get help from my son across all phases!     I am really happy with the result, here they are in all their whiteness:  **What message did we hid in there? Stay tuned tomorrow for the last demo!** *PS. Thanks to colleague AR about having kids do some of the job - that worked great!*
 
×
Reply to moio
Day 4 diary: scale up!
Today I dealt with the bigger version of the puzzle. Software scaled just fine!
About hardware I was lucky enough to get help from my son across all phases!

I am really happy with the result, here they are in all their whiteness:

What message did we hid in there? Stay tuned tomorrow for the last demo!
PS. Thanks to colleague AR about having kids do some of the job - that worked great!
---
# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

* Use asterisks
* for lists

This is an [example link](http://example.com/)

This is an ![example image](http://paste.opensuse.org/view/raw/68957446)

This is a user link @hans

This is a project link hw#some-cool-title
More Complex Markdown Help
Formatting Help
• Edit
• Preview
 
• 

  6 months ago by moio | Reply

  Day 5 diary: it's a wrap!

  Today I created a video to explain progress and results, enjoy!

  

  Tricky part was to get light right - so that it was clearly visible on video. Ended up with an inverted laptop screen covered with an opaque film - otherwise light comes polarized and all behavior is totally different!

×
Edit Comment 7709
# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

* Use asterisks
* for lists

This is an [example link](http://example.com/)

This is an ![example image](http://paste.opensuse.org/view/raw/68957446)

This is a user link @hans

This is a project link hw#some-cool-title
More Complex Markdown Help
Formatting Help
• Edit
• Preview
# Day 5 diary: it's a wrap! Today I created a video to explain progress and results, enjoy! [](https://vimeo.com/883383171) Tricky part was to get light right - so that it was clearly visible on video. Ended up with an inverted laptop screen covered with an opaque film - otherwise light comes polarized and all behavior is totally different!
 
×
Reply to moio
Day 5 diary: it's a wrap!
Today I created a video to explain progress and results, enjoy!

Tricky part was to get light right - so that it was clearly visible on video. Ended up with an inverted laptop screen covered with an opaque film - otherwise light comes polarized and all behavior is totally different!
---
# A First Level Header
## A Second Level Header

Use one asterisk to *emphasize*

Use two asterisks for **strong emphasis**

* Use asterisks
* for lists

This is an [example link](http://example.com/)

This is an ![example image](http://paste.opensuse.org/view/raw/68957446)

This is a user link @hans

This is a project link hw#some-cool-title
More Complex Markdown Help
Formatting Help
• Edit
• Preview