Minecraft is a game about exploring procedure-generated worlds. Each world is generated from a particular “seed” value, and sharing this seed value allows others to generate the same world in their own game. Recently, the distributed computing project Minecraft@Home set about trying to find the seed value of the world shown in the Minecraft title screen, and have succeeded in their goal.

The amount of work required to complete this task should not be underestimated. 137 users contributed 181 hosts with 231 GPUs to the effort, finding a solution in under 24 hours. The list of contributors to the project is a long one. It appears the method to find the seed involved comparing screenshots from various seed worlds to the original image. This took a lot of reverse engineering in order to calculate the camera FOV and other settings of the original capture, such that the results could be compared accurately. Interestingly, the group found two seeds that can generate the requisite world, suggesting the world generator code has some collisions between seed values.

We’re not sure what’s more astounding, the amount of work that went into the project, or that there’s a distributed computing project tackling advanced Minecraft research. Either way, we’re no strangers to Minecraft hacks around these parts. Video after the break.

source https://hackaday.com/2020/07/20/finding-the-random-seed-of-minecrafts-title-screen/

If you’re playing Texas Hold’em or other card games with a small group, you may get tired of shuffling over and over again. [3dprintedLife] was in just such a position, and realized there were no good automatic card shufflers in his budget. Instead, he elected to build one, and put in some extra functionality to corrupt the game to his whims.

The mechanicals of the machine took much development, as accurately handling and dispensing cards is a challenge, particularly with the loose tolerances of 3D printed parts. After developing a reliable transport mechanism, it was more than capable of shuffling a deck well with some basic commands.

However, the real magic comes from installing a camera and Raspberry Pi running OpenCV. This is capable of reading the value and suit of each card, and then stacking the deck in a particular order to suit the dealer’s wishes. It’s all controlled through a web interface and is capable of creating guaranteed wins in Blackjack and Texas Hold’em. Files are on Github for those eager to delve deeper into how the machine works.

The mechanism does such a beautiful job of shuffling, that your friends may not even notice the ruse. It goes to show that you should always have your wits about you when gambling with the aid of machines. Of course, if you wish only to create havoc, this Lego card machine gun may be more your speed. Video after the break.

[via Reddit]

source https://hackaday.com/2020/07/20/raspberry-pi-shuffler-is-computerized-card-shark/

Giving a 3D printer the ability to remove its own prints means that it can crank out part after part automatically, without relying on a human operator between jobs. [Damien Weber] has done exactly that to his Prusa MK3/S printer, with what he calls the Chain Production Add-on.

[Damien]’s approach is one we haven’t quite seen before. When printing is complete, a fan cools the part then an arm (with what looks like utility knife blades attached at an angle) swings up and behind the bed. The arm zips forward and scoops the print off the bed, dumping the finished part in the process. It’s all made from 3D printed parts, aluminum extrusion and hardware, two stepper motors, and a driver PCB. The GitHub repository linked above holds all the design files, but there is also a project page on PrusaPrinters.org.

Not quite sure how it all works? Watch it in action in the video embedded below.

We have seen quite a few different approaches for automatic part removal in the past. Literally punching prints off the bed is a thing we have seen, and we’ve also witnessed an industrial robot arm handle an entire print farm.

source https://hackaday.com/2020/07/20/automated-part-removal-gets-serious-with-the-chain-production-add-on/

Giving a 3D printer the ability to remove its own prints means that it can crank out part after part automatically, without relying on a human operator between jobs. [Damien Weber] has done exactly that to his Prusa MK3/S printer, with what he calls the Chain Production Add-on.

[Damien]’s approach is one we haven’t quite seen before. When printing is complete, a fan cools the part then an arm (with what looks like utility knife blades attached at an angle) swings up and behind the bed. The arm zips forward and scoops the print off the bed, dumping the finished part in the process. It’s all made from 3D printed parts, aluminum extrusion and hardware, two stepper motors, and a driver PCB. The GitHub repository linked above holds all the design files, but there is also a project page on PrusaPrinters.org.

Not quite sure how it all works? Watch it in action in the video embedded below.

We have seen quite a few different approaches for automatic part removal in the past. Literally punching prints off the bed is a thing we have seen, and we’ve also witnessed an industrial robot arm handle an entire print farm.

source https://hackaday.com/2020/07/20/automated-part-removal-gets-serious-with-the-chain-production-add-on/

Many of us will have at some point encountered a Z80 microprocessor, whether we’ve bare-metal programmed for it, or simply had a go at blasting some invaders on a game system using one. Like all the processors of its era, it’s got a relatively simple and accessible internal block diagram, so there’s a good chance that readers well even know how it works, too. But do any of know how it really works, down to the gate, transistor, and net level? [Goran] does, because he’s written a Z80 netlist simulator that allows the running of code alongside the examination of the chip and its signals. It’s not particularly fast, achieving a modest 2.3kHz clock speed when run of a fairly high-end PC, but we’re guessing readers needing to run Z80 code for anything other than learning would use the real thing anyway.

There’s a video of the software in operation which we’ve placed below the break, and we can see it will be a fascinating tool even to people who aren’t dedicated reverse engineers. To be able to bring up a logic analyzer view of the internals of a processor while it is in operation is truly astounding if you are used to it as a black box, and to have logic diagrams at your fingertips rather than puzzling out individual transistors really gives a window into what is going on.

This isn’t the only such simulator out there, in the past we’ve mentioned Visual6502, when we covered the Monster 6502.

source https://hackaday.com/2020/07/20/grok-the-z80-with-this-simulator/