CGAL Released, Computational Geometry Algorithms Library -- Laurent Rineau

By Laurent Rineau | Oct 23, 2024 11:58 AM | Tags: None

The CGAL Open Source Project is pleased to announce the recent releases of CGAL versions 5.5.5, 5.6.2, 6.0, and 6.0.1.

New CGAL versions: 5.5.5, 5.6.2, 6.0, and 6.0.1

by Laurent Rineau

From the article

CGAL version 6.0

CGAL version 6.0 was released on September 27, 2024. Following the discovery of early issues, version 6.0.1 was subsequently released on October 22, 2024.

This version is a major release, with many new features and improvements.

General changes

• C++17 Requirement: CGAL 6.0 requires a C++17 compatible compiler.
• GMP/MPFR Optional: GMP/MPFR are no longer mandatory; Boost.Multiprecision can be used.
• Qt6 Demos: All demos are now based on Qt6.
• Polyhedral Surface: The demo has been renamed to “CGAL Lab” and moved to its own directory in demo/Lab/.

New Packages

• Kinetic Space Partition: Partition of the space from planar input shapes.
• Kinetic Surface Reconstruction: Reconstructs surfaces from point clouds.
• Basic Viewer: Interactive visualization for various CGAL packages.
• Polygon Repair: Algorithms to repair 2D polygons and multipolygons.

Breaking Changes

• CMake Changes: UseCGAL.cmake removed; use CGAL::CGAL target instead.
• Kernel: Replaced boost::variant with std::variant and boost::optional with std::optional in the intersection functions.

Enhancements

• AABB Tree: Now supports 2D and 3D primitives.

Passing C++ STL Strings vs. String Views at the Windows C API Boundary -- Giovanni Dicanio

By Giovanni Dicanio | Oct 23, 2024 11:57 AM | Tags: None

A common question that is often asked is whether C++ STL string objects (like std::string/wstring) or string views (e.g. std::wstring_view) should be passed as string parameters at Windows C-interface API boundaries. The following articles tries to shed some light on this subject, answering that question:

Passing C++ STL Strings vs. String Views as Input Parameters at the Windows C API Boundary

by Giovanni Dicanio

From the article:

Passing STL std::[w]string objects at Win32 API boundaries is common for C++ code that calls into Win32 C-interface APIs. When is it safe to pass *string views* instead?

(...) the code will work fine. In fact, the wstring::c_str() method is guaranteed to return a null-terminated C-style string pointer.

On the other hand, if you pass a string view like std::wstring_view in that context, you’ll likely get some subtle bugs! Try experimenting with the above API and something like “Connie is learning C++” and string views!

Code Generation in Rust vs C++26 -- Barry Revzin

By Blog Staff | Oct 22, 2024 10:30 AM | Tags: None

Exploring how different languages solve the same problem often reveals interesting contrasts, especially when it comes to implementing powerful features like reflection. While C++26 aims to introduce introspection and code generation via P2996 and P3294, Rust’s approach using its derive macros offers a mature solution for code generation, even without introspection, highlighting different philosophies in language design and their practical applications.

Code Generation in Rust vs C++26

by Barry Revzin

From the article:

One of the things I like to do is compare how different languages solve the same problem — especially when they end up having very different approaches. It’s always educational. In this case, a bunch of us have been working hard on trying to get reflection — a really transformative language feature — into C++26. Fundamentally, reflection itself can be divided into two pieces:

1. Introspection — the ability to ask questions about your program during compilation
2. Code Generation — the ability to have your code write new code

P2996 (Reflection for C++26) is the (huge) core proposal that fundamentally deals with the first problem, along with setting the foundation for being able to extend this feature in lots of different directions in the future, including generation (for which our design is P3294). But introspection, while valuable, is only half of the piece. Andrei Alexandrescu went so far as to claim in his CppCon talk that introspection without generation is useless.

PVS-Studio 7.33: SN-DBS support

By Andrey Karpov | Oct 20, 2024 02:14 AM | Tags: None

PVS-Studio 7.33 has been released. Check out the latest features, including SN-DBS support, C# user annotations, and other exciting updates! See more details in this note.

PVS-Studio 7.33: SN-DBS support

by Valerii Filatov

From the article:

To enhance the integration of PVS-Studio with Unreal Engine, we've introduced support for SN-DBS, a distributed build system. These changes apply to Unreal Engine 5.5. Learn more about using PVS-Studio with Unreal Engine in the documentation.

2024-10 Mailing Available

By Administrator | Oct 17, 2024 09:36 PM | Tags: None

The 2024-10 mailing of new standards papers is now available.

Synchronization Primitives in C++20 -- Shivam Kunwar

By Blog Staff | Oct 17, 2024 10:20 AM | Tags: None

In C++20, the standard library introduced new synchronization primitives: std::latch and std::barrier. These are the utilities designed to coordinate between concurrent threads.

Synchronization Primitives in C++20

by Shivam Kunwar

From the article:

What is a synchronization primitive?

In concurrent programming, synchronization primitives are the fundamental tools that help in managing the coordination, execution order, and data safety of multiple threads or processes that run concurrently.

Briefly said, they ensure that:

• multiple threads don’t simultaneously execute some specific segment of code (a “critical section”)
• the program and the data remain in a consistent state
• deadlocks (where threads wait indefinitely for resources) and race conditions (where the outcome depends on the timing of accessing the shared data by a thread) are prevented or managed

There are multiple synchronization primitives in C++; for example, mutual exclusion, condition variables, atomic operations, locking mechanisms, etc.

In C++20, we have two additional synchronization primitives: latches and barriers.

Let’s discuss both of them.

std::latch

A std::latch is a synchronization primitive that permits a certain number of count_down operations (decrements) before allowing one or more threads to pass the wait point. A latch cannot be reused once its internal counter reaches zero.

How do we use a latch?

• A std::latch object is created with an initial count.
• Multiple threads can decrement this count using the count_down method.
• Threads can call wait, which block until the internal count of the latch reaches zero.

 

30 days until Meeting C++ 2024!

By Meeting C++ | Oct 15, 2024 06:56 AM | Tags: meetingcpp conference community

Meeting C++ 2024 is just 30 days away! Come to Berlin and meet with the C++ Community and the C++ committee for 3 days!

The Schedule of Meeting C++ 2024

by Jens Weller

From the page:

Meeting C++ 2024 features 4 keynotes, 3 tracks onsite and one online track, the conference is live streamed from Berlin. All Tickets include access to the videos after the conference.

This years keynotes are Titus Winters, Hana Dusíková, Herb Sutter and Peter Sommerlad!

C++ semantics

By Andrey Karpov | Oct 15, 2024 04:47 AM | Tags: semantics parsing name resolution lookups

The PVS-Studio Team invite you to the webinar. Date: November 06, 2024, 12:00 PM UTC+1.

C++ semantics

by Yuri Minaev

Summary of the talk:

In this talk on the С++ semantics, we will take a look at symbols and name resolution. We will discuss different kinds of lookups, scope importing, overload resolution, as well as templates and their specifics. Speaker: Yuri Minaev.

Write Modern Code with Features of C++17 and C++20 -- Andreas Fertig

By Blog Staff | Oct 14, 2024 10:13 AM | Tags: None

When you transition from older C++ standards like C++11 or C++14 to the latest C++17 and C++20 it can be a tough journey. It's essential for writing clean and easy-to-maintain code, but many developers find the process challenging.

Write Modern Code with Features of C++17 and C++20

by Andreas Fertig

From the article:

Here are three common hurdles:

1. Variety of New Features

Adapting to C++17 and C++20 can be intimidating. As the latest standards offer a wide range of new features and syntax changes. One such feature is the introduction of structured bindings in C++17, which represents a shift from how variables were traditionally declared and accessed.

Old Way (C++14 and Earlier):

Before C++17, when you needed to unpack values from a pair or a tuple, you would typically do something like this:

Here, you need to use std::get<>() to access each element of the tuple, which is both verbose and less intuitive, especially when dealing with more complex data structures.

C++ Compile-Time Programming -- Yongwei Wu

By Wu Yongwei | Oct 13, 2024 08:04 AM | Tags: None

<img alt="ACCU" data-cke-saved-src="https://isocpp.org/files/img/logo.png" src="https://isocpp.org/files/img/logo.png" 225px;="" height:="" 60px;="" float:="" right;"="" style="float: right;">Programming at compile time has been possible in C++ for a long time. Yongwei Wu considers its past, present, and future.

C++ Compile-Time Programming

by Yongwei Wu

From the article:

Compile-time programming is a key feature of C++. It enables writing high-performance code often unattainable in other languages. This article explores its past, present, and future applications, highlighting the diverse possibilities in C++. We’ll briefly cover template metaprogramming, constexpr, variadic templates, static reflection, and more.