Posts

Use IA for 2D nesting, they said ...

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Well, I have gone down the rabbit hole of applying IA to solve free-form 2D nesting problems, but the results weren't what I expected.  However, I have learned a lot of things in the process, and created some software you might find useful, such as this  packer , which has nothing to do with AI (initially), but it is a basic Left-Bottom First packer.  The AI part comes in when you provide it with a somewhat "intelligent" parts sequence. And there, my friend, is where many different attempts and hours of AI training went. Let me explain what I did and how I did not accomplish much in the process: I had a collection of 2D part geometries and the results of a professional nesting tool applied to them. I thought I could use that to teach a model how to tell a dumb LBF to do better by either providing the optimal part sequence and/or rotation angle. I used different approaches to that, but I underestimated my ability to mess things up, so I ended up with six different transfor...

The problem with Clonezilla ...

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 This is just a reminder, as I seem to stumble with the same rock every now and then. The problem is the keyboard configuration and the sometimes quick time window to perform a cloning operation. All of it leads me sometimes to a number of failed attempts until I got it right. The culprit? Having passwords that use symbols that are mapped to different keys depending on the keyboard language selected. And no, selecting the UI language has nothing to do with that.  So the common symptom is my host system no longer allows the connection to the SMB share I use to store the images to (or to retrieve them from). So I first worry about potential incompatibility of the SMB versions and authentication modes. Then I think there might be I am not remembering a not so often used password right. And, eventually, I realized that the password I am typing at the terminal that I cannot read as it is not echoed back most likely contain the wrong symbols as I did not choose the right keyboard (w...

Using PyMeshLab

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This document summarizes some of the usage of the pymeshlab library. Unfortunately, the library has been through severe changes over time, so some methods are renamed and filter calling conventions are shifting too, which makes AI and humans mad :-) Core Concepts The MeshSet The MeshSet is the primary container for handling multiple mesh layers and applying filters. ms = pymeshlab.MeshSet() Mesh Objects Individual meshes within a MeshSet . They contain the geometry and attribute data. mesh = ms.current_mesh() Basic Operations Loading and Saving # Load a new mesh into the MeshSet ms.load_new_mesh("input.stl") # Save the currently selected mesh ms.save_current_mesh("output.stl", colormode=False) Layer Management # Get total number of meshes in the MeshSet count = ms.mesh_number() # Select a specific mesh by index ms.set_current_mesh(1) # Delete the currently active mesh ms.delete_current_mesh() # Control visibility (often used for merging) ms.set_cu...

The Problem: Why Batch Files Fail

  I recently encountered an unusual error when trying to pass certain filenames to a Python app as inputs. After a moment, I realized the troubled ones had a comma in their filename, which should be totally valid, isn't it? It turns out Windows Batch ( cmd.exe ) is built on legacy rules where the comma ( , ) , semicolon ( ; ) , and equals sign ( = ) are treated as delimiters, exactly like a space . When you drag a file named Data,Project.txt onto a .bat file: Explorer sends the raw string to the command processor. CMD sees the comma and splits the filename into two arguments: %1 becomes  Data  and %2 becomes Project.txt . The comma is deleted from the stream entirely ( 🤦 ). The Solutions: From Hack to Hero Method The "Ugly Hack" (Batch) The "Robust" Way (Shortcut) The "Pro" Way (PyInstaller) Setup Create a .bat file with %* Right-click .py > Create Shortcut Compile script to a standalone .exe The Trick python script.py "%*" Edit ...

Remote KVM

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I usually have Linux server boxes with only power and network cables. That works well most of the time, except when: You need to install the operating system. You screw up and render the system unresponsive, even after a power cycle. Then you realize you need to move a keyboard, mouse and display to that machine to see what is going on, and hopefully fix it. Not a big deal if you are in the next room, not ideal if you are in another city or country.  So after watching Dave's video , I decided it was time to start using these devices for my own good. And I learned a couple of interesting things while reviewing the features: There is an optional add-on, called Fingerbot, that can be used to act on a push button, like the reset or power button of your server remotely. That way you can even power off a misbehaving server, or power it back on after powering it down. That is especially useful if Wake-On-LAN is not possible at the moment (most computers do not come with that enabled). The...

Browser-based Peer to Peer file transfer

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On your home LAN, it is easy to send files from one device to another, but when you are away from home, things get trickier. Of course, if you are visiting a friend's home, a USB drive can be a useful tool for transferring files, but what if no one is available to move them? It is not uncommon to have a bunch of media files to share after a trip with family or friends. You can share these on social media (this is what they want you to do). However, there are several reasons you might want to keep them private, so the next question is how to share them without using cloud services.  Email comes to mind, but there are usually limits on the maximum size allowed for messages, and you might overload some recipients' mailboxes to the point where they fail to receive some of the content. And if you are a bit worried about using cloud services, email also involves some Internet servers, too.  Some peer-to-peer file sharing apps exist, but they are typically designed to allow files to ...

AI killed the video star.

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In the latest months, I have found myself questioning more and more often the shorts that YouTube is dropping on my feed. The point is not why they are there; the point is whether they are "real". And it is because the pervasive use of AI in video creation is making me now doubt everything I see.  There is an old Arab saying:  "Believe what you see and lay aside what you hear." Whether the origin is right or not, I cannot say( * ).  But what is becoming evident is that the power of the video as "proof" of an event is becoming thinner and thinner every day. After all, Hollywood built an empire on the idea of filming stories, where the premise is to make you believe them. However, we expect news reports to accurately convey real events, not fictional narratives. YouTube, TikTok, and the like are more about keeping us hooked on whatever crap we are interested in. Whether it is a healthy diet, running, fixing your motorbike, woodworking, plumbing, ... you nam...