LEDAS Blog

Since 1999, LEDAS has provided software development services to clients in a number of areas of hi-tech engineering, and as a result our team of developers works with a broad set of software tools.

At the very least, we need project management software, a compiler, and an operating system. In fact, we need more software than on that short list, but for now let’s focus on these three categories. They are the most critical for any software developer.

At LEDAS, these three main categories are represented primarily by Jira, Visual Studio, and Windows. Some other programs, such as for version control, text documents, spreadsheets, and presentations, are now freely available, so anybody can avoid those licensing costs.

Jira

Jira is often considered a leader in the market for project management ...

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Rubik’s 5x5x5 Cube Challenge

Sep 07, 2021 Ilya Lichman

The first four times we invited you to take on our game challenges, they all operated at the same level of difficulty for everyone — whether inverting the state of Conway's Life game, inventing ways to split a polymino, solving PLM anagrams, or composing a most beautiful fractal, given constraints.

With today’s challenge, you get to choose the level of difficulty. As the ideal — and the most accurate scale of difficulty known to man — we will use the skill levels from the Doom computer game (illustrated below), which incidentally is now 33 = 3*3*3 = 27 years old.

Why Doom, and Why Now?

When we first planned this Rubik’s cube challenge at the beginning of August, the stars aligned in a remarkable way. Judge for yourself:

LEDAS’ Intellectual Games Club Flourishes Online

Jul 01, 2021 Nikolay Prytkov, Ivan Rykov

“Our life is but a game,” sang Herman during the opera The Queen of Spades. Which game exactly? That one everyone should decide for himself.

We at LEDAS love playing games, as is probably the case with most developers around the world. Sometimes we prefer video games; other times, board games that provide the extra special kind of social enjoyment that allows us to develop good relations with teammates and colleagues.

We have a collection of board games in our coffee room and so during that “before pandemic” era we sometimes stayed late in the office playing them.

People have always been curious, searching for answers to many questions. Discovering an answer is emotionally comparable to scoring a goal during a football World Cup finale. Over the decades, mass media ...

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LEDAS Fractal Contest

Jun 09, 2021 Ilya Lichman

“Good! He did not have enough imagination to become a mathematician.”
— Hilbert's response upon hearing that one of his students had dropped out to study poetry.
(wiki)

Do you love mathematics as much as we do? Over the years, we’ve developed five constraint solvers and a lot of other software that’s mathematically sophisticated, and through that we have gained some understanding in this area of expertise.

So, today we want to talk about the seemingly impossible: things that you can understand but also seem like just a fantasy. Yes, right now! The beauty of mathematics is that there really are a lot of remarkable sides to it that everyone can enjoy.

For example, can you imagine a ...

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LEDAS' Birthday on Mathematician's Day

Apr 01, 2021 Ilya Lichman

Today is April 1 and we are 22 years old! We are proud of our history, but we could not imagine that a whole year of remote work would become a part of it. Fortunately, we are starting to return to the office step by step. Today we will celebrate our birthday with a small group of employees who have already been vaccinated.

However, we hope that we will meet together and continue celebrating in June on the seashore. In fact, this is not a sea, but a reservoir next to the dam. It is so large that at some points the opposite shore is not visible, that is why we call it the Ob Sea. By the way, at the beginning of April the Ob Sea is still ...

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Pivot Points In the Story of LEDAS

Mar 30, 2021 Alexey Ershov

It’s just before our 22nd anniversary on April 1, and looking back at the history of LEDAS, I see that the first years from each decade were, for our company, the really important ones. Often, these years started new stories and finalized old ones.

Arguably, 2011 was the most pivotal year in LEDAS’ history. Let me list the top five events that happened to our company ten years ago:

  1. Top management changed completely when co-founder David Levin stepped back as CEO and took on the role of Chairman of the Board. A new generation of young managers, aged around 30 years old, now occupied the CEO, CTO, and COO positions.
  2. Thanks to advice from an industry mate, LEDAS decided to focus mostly on high-quality software R&D (research and ...

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LEDAS Anagrams: Seawater Folds

Mar 01, 2021 Ilya Lichman

One aspect of intelligence is the ability to quickly run through a range of options. It is not that people must get through alternatives faster than a computer, but that they move systematically and purposefully from one option (when found to be wrong) to another option, finding the better direction in which to move. We are talking here about the ability to adjust the brain to the specifics of a task, about the rapid training of one’s own neural network.

Today we invite you to come up with anagrams that are meaningful to you and that involve our primary topic of interest, CAD/CAE/CAM/PLM/BIM. When we program computers to work with anagrams, they go through words in a dictionary incredibly quickly, trying the various permutations and analyzing the ...

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Some 16 years ago, LEDAS founded isicad.ru, which since has become the leading Russian-language Web portal covering engineering software. Over the years, it has published about 10,000 articles on topics like CAD, CAM, CAE, PLM, BIM, generative design, cloud technology, additive manufacturing, and digital twins.

The portal reports on developments in both the Russian and global markets. It offers readers news articles, interviews on technological advances, trends in innovation, financial results, and described the business development of significant companies. As well, isicad.ru placed promotional materials on the portal, including the home page, for nearly all of the major players in the Russian market – Ansys, Autodesk, ASCON, Dassault Systemes, Hexagon, PTC, Siemens Digital Software, Top Systems, and more.

LEDAS' long-running, actively-maintained isicad.ru portal, along with the CAD conferences held ...

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From LEDAS: The Polyomino Contest!

Dec 03, 2020 Ilya Lichman

You may have encountered polyominoes at some point in your life, because they are used in puzzles popular for more than 100 years, including ones like Tetris.

A polyomino is a plane geometric figure formed by joining one or more equal squares, edge to edge. The name was devised by Solomon Golomb in 1953 in a now-classic textbook, and then popularized by Martin Gardner in 1960; see the “Mathematical Games” column in Scientific American.

Today we’ll play with our updated LEDAS logo, which we released a year ago. As you can see, it consists of four pentominoes. A pentomino is a polyomino of order 5, i.e. 5 equal-sized squares connected edge-to-edge.

Splitting the LEDAS Logo Into Polyominos

Our question today is this: what is the number ...

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Personal Management in Agile Style

Nov 23, 2020 Ivan Rykov

Some people are just naturally efficient. Others (me being one of them) are in a constant search for methods and tools that would make us more productive. There have been dozens of times when I tried this or that productivity technique or time management system and each time, after days or weeks of enthusiastic usage, I found myself dropping them. (I’m not saying, though, that all of that was in vain: enthusiasm means a lot, because it helps a lot!)

I have, however, been using my current productivity tool for more than a year now, which for me is a long period of time. As a result of my experience, I’d like to share in this article some ideas that could be useful to you in maintaining a personal management ...

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Our Engine-mounted Table

Oct 29, 2020 Polina Vlasova

Due to COVID-19, all of our employees at LEDAS continue to work remotely, but we decided not to waste time by being just at home. We did a minor upgrade to our office interior in anticipation of the day we return to our headquarters.

You probably know that one of the key competencies of LEDAS is a set of tools for computer-aided design, some of which you can see in our CAD Solutions list, and so we used them to decorate our entrance hall with an exclusive, glass-topped table mounted on the cylinder block of an actual Mercedes-Benz engine. You can see the result, made by Alex, in the photo.

Engines, by the way, are produced not only by Mercedes Benz but also by us at LEDAS. You ...

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One hierarchy, many algorithms

Geometrical modeling projects often contain some form of central hierarchy of objects. A geometric kernel, for example, has a hierarchy of geometric entities. Another example is a geometric solver which has a hierarchy of objects and constraints. Simplified inheritance diagrams for these hierarchies are shown in the figures below.

Many routines/algorithms of other modules need to process all the entities in a hierarchy in a similar fashion, although with different implementation details. So, polymorphism naturally is used with these kinds of hierarchies.

Assuming we are talking about C++ (and this is usually the programming language of choice for algorithmic libraries in CAD), using virtual functions is the first consideration for implementing polymorphic behaviour.

However, a variety of routines applied to the entire hierarchy, ...

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LEDAS Life Contest

Aug 31, 2020 Ilya Lichman

Let’s go all the way back to 1970 and to the Game of Life. Also known simply as Life, this program is based on cellular automaton and was devised by British mathematician John Horton Conway.

The rules of Life

The rules of Life are simple: The universe in which Life is played is an infinite, two-dimensional grid of square cells. Each cell has one of two possible states, on or off, filled or empty, live or dead.

Each cell interacts only with its eight neighbours. Neighbour cells are adjacent horizontally, vertically, and diagonally.

Cells stay alive when they have two or three neighbours. Live cells with fewer than two, or more than three, live neighbours die, as if by underpopulation or overpopulation. Dead cells with exactly three live ...

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What Statistics Can Tell Us About SARS-CoV-2 Test Results

Antibody testing at LEDAS shows good results. What does it mean?

Jul 20, 2020 Nikolay Snytnikov

To better estimate the situation with СOVID-19 within our company LEDAS, we decided to make antibody testing available to our employees who work remotely since March. Fifty-three of our 70+ employees were interested, and so we organized out-of-lab testing thanks to Invitro’s laboratory service. Both IgM (early antibodies) and IgG (late antibodies) were examined, and the results were simple: all had zero positives for IgM, and one employee was positive for IgG.

We were able to congratulate ourselves for the zero result in early antibodies, meaning we are quite safe. But now we needed to focus on the late antibodies, as they provide more interesting information. Since we at LEDAS are now involved in more medical software projects, we considered this an opportunity to apply statistics to our ...

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This post was written by a LEDAS developer in his own blog, and now we repost it here. Focus on performance is the major goal in our projects, and we are going to publish more posts on this topic.

It is well-known that Debug build in Visual C++ is very slow compared to Release build, with the typical ratio about 10-20 times. Various reasons behind it are often stated, and some people even believe that it is inevitable because it is caused by lack of compiler optimizations.

If some issue happens only on a large dataset or in a real-time application, and it cannot be extracted into a smaller test case, then developer is forced to debug Release build. Which is rather painful ...

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LEDAS customer map

May 24, 2020 Alexey Ershov

The geography of the locations of our customers has changed considerably during the 20+ years of LEDAS’ history.

From looking at the map of our customers (below), you may think that we began in our home country and then expanded abroad. In fact, the reverse is true, because in its first years LEDAS mostly provided CAD and CAM software development services in Europe, namely to Dassault Systèmes from France.

In the beginning, we concentrated on developing geometric solvers and engines, a rather narrow field, yet very sensitive to quality. Over the following years, overall CAD software market was our primary focus.

In late 2000s, LEDAS Geometric Solver (LGS) was our flagship product, along with our high-quality R&D (research and development) services for CAD and PLM. Many ...

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How to Hack C++ with Templates and Friends

May 07, 2020 Andrey Karpovskii

Templates are a very powerful feature in C++, because they allow you to write generic programs that accept a data type as an extra parameter. This feature of them means that we don’t need to repeat similar code for different data types.

When templates were first introduced in C++, their capabilities were unforeseen. Since then templates have grown into a separate functional language inside of C++. This language has its own syntax, rules, and huge number of specifics, one of which I will discuss later.

How Templates Work

Each template defines a family of functions. It is, after all, a functional language. But the family does not produce any code on its own. Instead, the compiler generates code only for functions that are actually used in the program. This process ...

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In these work-from-home times, we are seeing a burst of interest in LEDAS Cloud Platform (LCP) as nearly every day our team shows demos to prospective customers.

LCP is a platform on which applications are developed for online 3D modeling, and so I think that the primary reason for the record levels of interest is that companies are beginning to realize that the world and the way in which we organize it might not be the same after the pandemic ends. Businesses are asking their engineers to work from home, and this may well become the way of the future.

With remote work now a must, and because it is likely that full-scale and partial lockdowns will last for many more months, Web and cloud solutions are ...

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On C++ code bloat

Apr 08, 2020
Foreword by Alexey Ershov:
After publishing my post about C++'s new standard, in which slow compilation time is highlighted as the most bothersome C++ feature, one of our developers responded with a link to his post from 2018. This post is more technically involved with the problems that code bloat have on slow compilation times. It focuses primarily on the negative effect of extensive templates, headers, and inlines on compile times, but then also provides the programming practices to overcome these problems. Read it here now.


The C++ language is known for its slow build times. This problem is not present in the world of pure C, which might give a hint that the problem is caused by some ...

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Today is the 21st anniversary of LEDAS!

Apr 01, 2020 Alexey Ershov
This is a proper moment to read about our history. Let me put some points here.

  • 2019 LEDAS celebrates its 20th anniversary by moving to a new own 1,000-square-meter headquarters office at Academpark.
  • 2017 LEDAS releases its LEDAS Cloud Platform (LCP) as an easy way to build Web-based CAD solutions.
  • 2016 LEDAS signs a long-term cooperation agreement with a major US-based digital dentistry company.
  • 2015 LEDAS lands its biggest service contract to date for developing a full-scale Web solution in the area of building information modeling (BIM)
  • 2011 LEDAS sells some of its intellectual property and staff to Bricsys NV, including its LGS 2D/3D geometric solver. After the sale of IP rights concludes, LEDAS renews its top management and pivots the company to focus on high-end R&D ...

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