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Showing posts older than #25422 · Back to latest

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Post #25417 11
Spatial Canvas: a single-file C++/Win32/Direct3D 11 zoomable window manager that puts your live windows on an infinite canvas

I've been building a zoomable-UI (ZUI) window manager for Windows in C++ and

wanted to share the architecture, since the interesting part is how you keep

dozens of live windows rendering at once.



Each window is captured via Windows.Graphics.Capture (FreeThreaded frame pool,

poll-based, lock-free) into a persistent D3D11 texture, then drawn as a

1:1-pixel textured quad in world space on a borderless fullscreen swapchain.

Pan/zoom is just a camera transform. A D2D/DWrite overlay draws the rest:

title labels, a world-anchored dot grid, the minimap, docks.



The hard problem: if you move/hide windows off-screen to composite them, DWM

occlusion-throttles them and Windows.Graphics.Capture starts returning black

or stale frames. Your canvas fills with black tiles. So there is no input

simulation and no off-screen hiding. Instead, each window "parks" in a 2px

visible strip at the bottom of the primary monitor — 2px is enough that DWM

keeps compositing it, so the capture stays live, but it's hidden behind the

canvas. When you cross a zoom threshold (or double-click), the real HWND is

moved (SetWindowPos) onto its quad's screen rect and given focus; now you're

typing into the actual window, not a proxy. Pull back and it returns to the

strip. Two states per window: parked (live texture on the canvas) and

swapped-in (the real window).



Other bits:

\- Single translation unit (\~3300 lines, Canvas.cpp), entry RunCanvasApp().

\- Idle-throttled main loop (dirty flag + MsgWaitForMultipleObjectsEx) so it

doesn't burn the GPU when nothing changes.

\- Device-lost (TDR / sleep-wake) does a full D3D/D2D/WGC rebuild; an unhandled-

exception filter un-parks windows on crash so nothing is stranded in the strip.

\- Single 559 KB exe, statically linked — no .NET / VC redist.



A few things that bit me along the way:

\- IsBorderRequired(false) / the borderless-capture path black out capture on

some Windows builds — removed.

\- Content-sized CopySubresourceRegion + a drain-to-newest loop also produced

black tiles; a single TryGetNextFrame + full CopyResource is the proven path.

\- Added a cbuffer field the pixel shader reads, but bound the cbuffer only to

the vertex stage → every tile came out alpha=0 (invisible). If a stage reads

a cbuffer, bind it to that stage.



Repo + 30s demo: https://github.com/13auth/spatial-canvas



It's an early prototype and I'd genuinely appreciate critique on the capture/

compositing approach. (Heads-up: source-available but not OSS-licensed — happy

to explain the reasoning in the comments.)

https://redd.it/1u52eim
@r_cpp
GitHub GitHub - 13auth/spatial-canvas: Spatial Canvas - canli Windows pencerelerini sonsuz zoom'lanabilir tuvale yerlestiren pencere yoneticisi… Spatial Canvas - canli Windows pencerelerini sonsuz zoom'lanabilir tuvale yerlestiren pencere yoneticisi (WGC + park&swap, tek exe) - 13auth/spatial-canvas
Post #25415 12
Crazy idea: reducing function coloring in function templates and enabling reuse, is it possible by caller-injected marker?

I was reading a paper about resumable functions short ago and I wonder if a language extendion would be possible that would work the following way:


// Poor man's syntax
std::copyif(myrange, coawaitable (...) { coawait ... });

How would it work? Taking advantage that templates are code to be generated, at the place where the function is called, the compiler would generate a coawait for the function, making it reusable.




https://redd.it/1u4nyp5
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Post #25411 18
Efficient C++ Programming on Modern 64-bit CPUs, part 1 of Chapter 4

Well, I'm starting to publish (VERY DRAFT) Chapters from my (and Dmytro Ivanchykhin's) upcoming book, "Efficient C++ Programming for Modern 64-bit CPUs". Comments are extremely welcome (as before, we're committed to fixing all the issues highlighted in comments).

The first installment is the first part of Chapter 4: https://6it.dev/blog/on-cpu-physics-and-cpu-cycles-80730

In Vol. 1, the most interesting will probably be Chapter 9, with about 200 (sic!) practical de-pessimization hints.

Beware: this is not a book on optimizations (though some techniques will be covered in Appendixes A and B in Vol. 2) - this is a book on de-pessimizations; for optimizations - please refer to the excellent book by Denis Bakhvalov (though we're sure that de-pessimizations should be seen as a prerequisite for optimizations 😉).

Bracing for impact...

https://redd.it/1u3t63r
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Post #25409 16
What would make you consider using a new sorting algo?

I've been working on a parallel integer sorting algorithm and benchmarking it against ipso, parlay's integer sort (radix ) etc.

For people who work on databases, analytics systems, HPC, compilers, or other performance-sensitive software, what feature would you need before seriously considering a new sorting implementation?

Examples:

Better throughput?
 Better scaling? (on both key size and input size )
Lower memory overhead?
 NUMA results?
ARM benchmarks?
 Stable sorting?
Key-value sorting?
 Something else?

My algo currently aims to fix the scaling issue with radix , it gets slower if you increase the key size. And providing support for 128 bits , as most parallel radix implementation only support 64 bits in a single pass (for 128 bits or higher you need to multiple stable passes.

I'd especially like to hear from people who have actually deployed or evaluated sorting implementations in production systems.

Basically the end goal is to build something that is actually useful to someone.

https://redd.it/1u3p7nd
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Post #25408 13
Tau Parser - a parsing library for C++ for Boolean grammars (CFG + conjunction + negation)

[https://github.com/IDNI/parser](https://github.com/IDNI/parser)

Tau Parser handles Boolean grammars: context-free, conjunction and negation. You can write something like `identifier & ~keyword` directly in the grammar to match any identifier that isn't a reserved word. No separate lexer hack, no keyword table living in your host code.

The grammar format (TGF) is EBNF-like and readable. Here's keyword-exclusion in practice:

identifier => (alpha | '_') (alnum | '_')* & ~keyword.
keyword => "let" | "if" | "else" | "while" | "fn" | "return".

* Earley-based, so left recursion works, no grammar refactoring.
* Handles ambiguity natively (full parse forest available), but auto-disambiguation gives you a single tree by default with zero configuration. You can switch it off per-nonterminal when you actually want the alternatives.
* Header-only after codegen. Run `tgf calc.tgf gen`, include the generated header, and parse:



auto r = calc_parser::instance().parse(input, len);
if (r.found) r.get_tree()->to_print(std::cout);

* The `tgf` CLI also ships an interactive REPL and a test runner for `.tgf.test` files with tree-shape assertions.
* Tree shaping (`@trim`, u/inline) lets you strip whitespace/punctuation and collapse wrapper nodes so you get a clean AST.
* Platform parity across Linux, macOS, Windows (mingw-w64), and WASM/Emscripten.

Boolean grammars can also express some things beyond context-free e.g. requiring two productions to derive the *same* string, or asserting a span does *not* match a production — so certain constraints that'd normally need a separate validation pass live in the grammar instead.

**Status:** alpha, under active development toward 1.0.

https://redd.it/1u3frd5
@r_cpp
GitHub GitHub - IDNI/parser: IDNI's parser library IDNI's parser library. Contribute to IDNI/parser development by creating an account on GitHub.
Post #25407 13
nobs: my take on SW builds

Hey guys, for about a year and a half I've been working on a build tool called nobs (normal build system). Recently I put together a website and some example builds for existing projects and thought I may as well show it to the world. (link) (you can find examples on Github)

As for the motivation and what it brings to the table: I wanted a build description that makes artifacts and their boundaries explicit. A lot of C/C++ projects eventually grow into one large build context: a long list of source files, include paths, defines and special cases. That works, but it can make it hard to see what is being built, which sources belong to which artifact, and where one component ends and another begins. nobs is my attempt to model that more directly. It also makes cross-platform and compiler-specific differences easier to keep under control.

In case you decide to try it out, I've had good results with giving the manual to an AI assistant. The output usually still needs some polishing, but it has been useful for producing the kind of build descriptions I need. Let me know what you think. gn



https://redd.it/1u3bkxk
@r_cpp
nobs.build nobs build tool A small declarative build tool for C and C++ projects.
Post #25405 13
How to stop being absolutely psychotically obsessed with making “beautiful” code

I love C++. I love C as well. I have since the day I touched it in around 7th grade. Now I’ve graduated college and still love it all these years later and while my GitHub is FULL of projects, almost all of them are unfinished because of my obsessive tendencies. Just for an example, I have a 3D graphics renderer which I made with OpenGL which I have redone 16 TIMES and only once did I actually finish it and I’m still not happy with it compared to others programs. I’ve done the same with a Vulkan renderer which is unfinished and a Gameboy emulator which is also unfinished, as well as many others.

I’m dealing with the same thing now as I took a break after school from projects to chill and now started a new project which is a raycaster style game with SDL2, and at first all was well. That didn’t last long. Just from making a clean interface for a Point or a Vector is driving me insane, and the map layout as well as many many other things. I swear I’ve already rewritten half of it about 4 times now. And i can’t stand mixing C code (I LOVE C but not when it’s near C++ code) and C++ code and with SDL2 having many C-like paradigms, it is driving me genuinely insane. It gets so bad that I just get angry and stop programming and next thing I know I’m in another 2 week slump.

I never really have this problem with C as it doesn’t have as many ways to do things, so I’ve finished quite a few projects in C such as a few kernel drivers and a graphics engine. But I would really like to hone my skills in C++ a little more since it seems that in the graphics industry C++ is the de facto standard. The thing isnt that I don’t know the language either; I just get so in my head about it.

I really want to get at least one more C++ project finished before I begin seriously applying to more jobs because I want to show off my skill in it from all these years of using it. But at this point I’m beginning to just think I should stick to C as I’m just too neurotic about things.

What are your opinions or methods to get out of this overly obsessive perfectionist mindset and just make a project?

https://redd.it/1u333wm
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Post #25403 11
grpcpp uses absl (synchronization, log, .. ?) but so much log libraries

grpcpp/grpcpp.h but libgrpc++ (why in same lib different names ?)



libabsl_vlog_config_internal.so.20240722 (libc6,x86-64)

libabsl_vlog_config_internal.so (libc6,x86-64)

libabsl_raw_logging_internal.so.20240722 (libc6,x86-64)

libabsl_raw_logging_internal.so (libc6,x86-64)

libabsl_log_sink.so.20240722 (libc6,x86-64)

libabsl_log_sink.so (libc6,x86-64)

libabsl_log_severity.so.20240722 (libc6,x86-64)

libabsl_log_severity.so (libc6,x86-64)

libabsl_log_internal_proto.so.20240722 (libc6,x86-64)

libabsl_log_internal_proto.so (libc6,x86-64)

libabsl_log_internal_nullguard.so.20240722 (libc6,x86-64)

libabsl_log_internal_nullguard.so (libc6,x86-64)

libabsl_log_internal_message.so.20240722 (libc6,x86-64)

libabsl_log_internal_message.so (libc6,x86-64)

libabsl_log_internal_log_sink_set.so.20240722 (libc6,x86-64)

libabsl_log_internal_log_sink_set.so (libc6,x86-64)

libabsl_log_internal_globals.so.20240722 (libc6,x86-64)

libabsl_log_internal_globals.so (libc6,x86-64)

libabsl_log_internal_format.so.20240722 (libc6,x86-64)

libabsl_log_internal_format.so (libc6,x86-64)

libabsl_log_internal_fnmatch.so.20240722 (libc6,x86-64)

libabsl_log_internal_fnmatch.so (libc6,x86-64)

libabsl_log_internal_conditions.so.20240722 (libc6,x86-64)

libabsl_log_internal_conditions.so (libc6,x86-64)

libabsl_log_internal_check_op.so.20240722 (libc6,x86-64)

libabsl_log_internal_check_op.so (libc6,x86-64)

libabsl_log_initialize.so.20240722 (libc6,x86-64)

libabsl_log_initialize.so (libc6,x86-64)

libabsl_log_globals.so.20240722 (libc6,x86-64)

libabsl_log_globals.so (libc6,x86-64)

libabsl_log_flags.so.20240722 (libc6,x86-64)

libabsl_log_flags.so (libc6,x86-64)

libabsl_log_entry.so.20240722 (libc6,x86-64)

libabsl_log_entry.so (libc6,x86-64)

what`s the truth ?

thanks in advance, andi

https://redd.it/1u2uvsh
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