15 Years of Shader Minification

is there HN equivalent on game industry??

Regarding bytecode delivery, have you seen SPIR-V?

As for modules, avoiding them is a performance feature since it is easier to optimize code when you compile everything in one unit. Rather than go toward modules, modern graphics has moved away from them by removing dynamic linking from newer shader languages such as SPIR-V. I believe a limited form of dynamic linking was later introduced in the form of graphics pipeline libraries for avoiding performance issues from a combinatoric explosion of partially redundant compilations when translating shaders from Direct3D 11 and earlier, but for anything outside of translating other APIs, you are supposed to avoid using that as far as I know.

I cannot answer this for him, but I can speculate on the answer to your first question. The transformations he described his minifier applying do not change the code from the perspective of the compiler in any meaningful way, so the end result should have no performance difference. The only possible exception is the inlining, but the compiler likely would have done that anyway, so the end result should still have no difference.

To state that more precisely, everything is going to be translated into a SSA syntax in a compiler pass at some point. At that point, much of what he described should be either something the toolchain would have done (such as comment removal by the preprocessor) or effectively undone (such as the variable name reuse since by definition SSA makes each variable name be used exactly once). The rest should converge to the same result after subsequent optimization passes (such as an inlining pass). If you find a performance difference from using his tool, file a bug report with your compiler’s authors.

Most transformations don't change the code that's executed.

  const float x = sin(2);
  const float y = 2;

If you define these two consts, we can inline y everywhere it's used. But by default, we don't inline x as it would lead to more work at runtime (maybe it doesn't matter for sin, but other function calls can be expensive). If you notice performance issues, please file a bug.

Renaming uniforms is optional (there's a flag). If you use C++, you can generate a .h header file that contains both the minified shader and macros that tell you how they've been renamed.

So Shader Minifier will generate macros like:

  # define VAR_time "f"

to tell you that "time" is now called "f" and you can use VAR_time in your C++ code.

do you actually needs recursivity for that ?

Thankfully that’s not what the article is about, three paragraphs later it is noticed this has no savings after compression.

The author is referencing the demo scene, where they often have to meet very tight budgets in terms of space, so everyone is on an equal footing and it makes for very interesting wow moments.

Thanks! To be fair, there have been a few years without a single commit: https://github.com/laurentlb/shader-minifier/graphs/contribu... (before 2013, the code was in a private svn repo).

I also enjoy alternating work between multiple of my hobby projects, and I find it refreshing to come back to this F# codebase once in a while. :)