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Welcome to Cemetech! Since 2000, Cemetech (pronounced KE'me'tek) has been teaching programming and electronics and developing software and hardware. Among Cemetech's specialties are TI, HP, and Casio graphing calculators like the TI-84 Plus, TI-Nspire, HP Prime, and Casio Prizm, embedded and DIY electronics, and computer and web programming. Cemetech provides a safe, friendly space for people to learn, show off projects, and share knowledge and expertise. Our staff of friendly volunteers hang out on our forum and IRC and SAX chatrooms, and are happy to help.
From Cemetech Game Projects to Startup: Geopipe
Published by Alex on July 10, 2017 at 9:33:47 AM CST | Discuss this article (7)

I recently sat down with two Cemetech administrators: elfprince13, or Thomas Dickerson, and our founder KermMartian, or Christopher Mitchell. Over the past year, they've been busy working together on their startup, Geopipe. Geopipe automatically builds detailed virtual models of the real world, and licensing these immersive models of the world to architects, urban designers, special effects artists, video game designers, and many others. Geopipe leverages proprietary algorithms to automatically generate immersive models of the world from existing sensor data. They take 2D and 3D data like satellite photos, maps, laser scans, terrain contours, and more, and use machine learning to analyze and understand the data. Their algorithms then reconstruct models at configurable levels of detail to meet the needs of a wide variety of customers. Today, they enter the next step in their quest, a 12-week program called Techstars.

Through this interview we'll see how this idea arose as a challenge that they each tackled in separate environments; Thomas in Freebuild and Christopher in SparseWorld. We'll touch on how the similarities of FreeBuild and SparseWorld brought the two of them together and how the ideas behind each of those projects helped spawn Geopipe.

Here's a video that introduces Geopipe and shows Christopher and Thomas onstage presenting their company to investors.

Read the full interview >>

Accessible Tech: VR and Calcs for the Visually Challenged
Published by KermMartian on July 6, 2017 at 11:45:27 PM CST | Discuss this article (8)

by Thomas Dickerson and Christopher Mitchell

Over the last few years, we have been happy to see an increasing amount of technology designed with accessibility in mind. One of the first examples that we saw was the Orion TI-84 Plus graphing calculator, a modified TI-84 Plus designed by Orbit Research for blind users. When we were at SIGGRAPH 2016 last year, we also VR viewing technology specifically tailored to nearsighted users such as those common in the tech community. We'd like to tell you more about each of those projects, and we'd like to open this up as a discussion about how you think technology can or should be made accessible to more users in the future.

The Orion TI-84 Plus Talking Graphing Calculator

We first encountered the Orion TI-84 Plus back in 2013 at our first T^3 conference. Back over four years ago, Shaun "Merthsoft" McFall described this initial encounter with an accessible graphing calculator: "It was quite an amazing device. When graphing it plays pitches for the Y value of the graph, the same while tracing. When the value is negative the unit vibrates. When on the home screen, it talks out the answer of the equation you enter, and you can put it in a mode where it tells you all the keys youíve pressed. We were curious how easy it was to learn the keypad, and Ken [Perry, a visually impaired user and researcher] assured us that itís very easy to pick up and learn, and that he had no trouble whatsoever." I eventually got an Orion TI-84 Plus of my very own to play with, and found it to be a fascinating tool.

The calculator itself is a classic TI-84 Plus, loaded with a custom OS version, with an extra module semi-permanently attached to the top. I won't exhaustively replicate the list of features we previously published in 2013, but the upshot is that it can speak the math and menus on the screen, as well as make tones and vibrate to represent graphed plots. To demonstrate other ways to visualize graphs, my Orion TI-84 Plus also came with a set of printed, embossed plots that you can feel to "see" the shape of a graphed plot. If you're looking for a full technical teardown, our friends at TI-Planet also posted a hands-on review of the Orion TI-84 Plus for your enjoyment and edification. Since we're a community of DIYers and hackers, they even explored clever ways to play music using the Orion module.

The Orion is certainly a technically impressive tool, and Orbit Research did a great job of creating a module that provides a lot of extra power with minimal hardware modification to the original TI-84 Plus. Perhaps its bigger claim to fame, though, is in its role as a tool for the visually impaired to explore math just as fully as the rest of us. The problem of being able to use a calculator as a blind or visually impaired person is probably something most sighted people would never even consider, but once you think about it, a whole host of problems pop up. First, there's the problem of just doing arithmetic with a calculator in the first place. Perhaps text-to-speech software and OSes' built-in calculator tools could do this, but that's certainly not a good solution for a classroom setting. Then, there's the problem of doing any kind of non-trivial math, working with lists and probability and statistics, and finally, the problem of finding a non-visual way to represent the shape of graphs and plots. The Orion module cleverly solves all these problems, allowing blind or visually impaired users to hear the keys that they're typing, the menus they're navigating, and even the shapes and axis crossings of the graphs they're plotting. Considering the Orion device, and trying to use it with my eyes closed, made me think about so many other technologies that must be challenging or even impossible to use without reasonably good eyesight. I applaud Orbit Research and TI for exploring this, and hopefully in the future more technologies (and at a lower price point) will look to solve similar problems.

VR for the Nearsighted
The Stanford Computational Imaging Lab has a long history of working on problems at the intersection of display technology and human ocular physiology, including the design of an eyeglasses-free display that could provide automatically vision-corrected images to users.

More recently, they've been working to address issues in virtual reality headsets (and other "near-eye displays"). Human vision builds on two separate types of eye movement. When your eyes swivel to look at a new object ("vergence"), they must also relax or contract the shape of the eye itself to alter the depth of focus. In a traditional near-eye display, the physical surface that a user is looking at remains in the same place, and so these visual cues become mismatched from one other, causing visual discomfort and fatigue, as well as potentially more painful symptoms.

At last year's SIGGRAPH we got to test their prototype VR display, using a number of different corrective display modes, including a "monovision" mode adapted from treatments for presbyopia, where one eye is used to focus exclusively on near objects, and one eye to focus exclusively on far objects. While that display, pictured below, is too bulky to be used as a wearable headset in the near future, we look forward to seeing how the technology progresses.

Accommodation-invariant Near-eye Displays

At this year's SIGGRAPH they'll be presenting more fully on those findings, but a short video has already been made available:

In a unification of their work on accessibility and physically-adaptive VR displays, they've also recently published a paper on correcting visual refractive errors in VR, using a hacked Samsung Gear VR, capable of moving the position of your phone relative to the lenses.

Contest 20: Transit Time
Published by jonbush on June 24, 2017 at 3:18:25 AM CST | Discuss this article (26)

Cemetech Contest #20, Transit Time is all about different modes of transport. The development of transportation technologies has facilitated modern life by enabling the spread of people, goods, and ideas. Computerization has further advanced transportation, improving safety, efficiency, and ease of operation, along with many other aspects. By encouraging Cemetech members to create programs centered around a multitude of transportation modes, Transit Time celebrates the positive impact that transportation has on our lives.

Transit Time will be divided into three two-week segments, each focusing on one of the three realms in which transportation commonly takes place (land, water, and air). For each segment of the contest, you must choose a mode of transport for that realm, and create a program that is somehow related to your choice. Additionally, contestants may choose to create an entry for the realm of space, in lieu of one of the three traditional realms.

At the end of each two-week period, contestants must submit their programs for the respective realm. The winning program for each realm will be selected by a poll of Cemetech users, with the creator receiving a $10 Steam credit. At the conclusion of the contest, an overall winner will be selected by a panel of judges. The overall winner will receive a (additional) $20 gift certificate. Entries for all platforms, and in any programming language will be accepted.

Contest timeline
▪ June 24th: Contest begins
▪ July 8th: Land submissions due
▪ July 22nd: Water submissions due
▪ August 5th: Air submissions due

▪ Please maintain a contest thread documenting the progress of your entries.
▪ Entries must be submitted by 11:59 PM Eastern Time on the dates listed above.
▪ You may receive help from other Cemetech members, provided that communication is done publicly through the forum or through SAX/IRC.
▪ Fine print rules can be found here.

EDIT: Winners can opt to receive a different gift card or item of equivalent value.

Cemetech Minecraft Server Upgraded to 1.12
Published by KermMartian on June 21, 2017 at 12:41:12 PM CST | Discuss this article (1)

Two weeks ago, Mojang released Minecraft 1.12, the so-called "World of Color Update". After waiting for Spigot's CraftBukkit clone and our relevant plugins to be updated, I'm happy to say that the server is now running version 1.12. If you enjoy playing our "Intellectual Survival" style, you now have access to more material options like Terra Cotta and Concrete, recipe and knowledge books, and the Illusioner and Parrot mobs. In addition, to celebrate the upgrade and give you a source for the new materials available, moderator Daniel "tifreak8x" Thorneycroft has opened a Mesa Mining World, accessible from spawn, for a limited one-week mining period.

Unfortunately, the upgrade was not without a hiccup or two. Specifically, we discovered that town, nation, and player balances appeared to have been cleared, and weren't able to intercede soon enough to prevent towns from falling. Our postmortem revealed that the problem was that iConomy Recreation, our economy plugin, uses a space in its plugin name in an important internal file, plugin.yml. Unfortunately, Spigot 1.12 now disallows this, so iConomy was not loaded, which we didn't notice. This made Essentials use its built-in file-based economy system, defaulting everyone to starting balances and currency ($0 for towns/nations, $30 for players) instead. The entire server has been restored to its state as of the morning of June 19th, so a few players who cashed in Lapis Ore and deposited it lost that, and all signs that were in towns that fell are no longer recorded as proper signshops. We have been actively working to restore the lost signshops. Because players were restored along with the world, there will be no discrepancies between inventories and town contents. Please privately contact any moderator or administrator if you think you've spotted an issue of some sort.

As always, we welcome you on mc.cemetech.net to build cool structures and machines and engage with a lively, intelligent community of creative Minecrafters. Be sure to keep your eyes out for our many exciting special events as well!

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