Post chain review fixes: glslc on stdin, level A at the display's refresh

Stage 9 review: a user's Shadertoy file goes to glslc on its stdin, so no
source file is written anywhere (the old predictable name under
XDG_RUNTIME_DIR or /tmp was a symlink-clobber hazard). std's spawn does
all its allocation before fork and searches PATH on the stack after it,
said at the call. Level A redraws are paced by the display's refresh rate
(SDL_GetCurrentDisplayMode), not a fixed 16 ms.

Shared files touched: gui.zig.

1 files changed, 3 insertions, 3 deletions

diff --git a/docs/render-pipeline.md b/docs/render-pipeline.md
index 254187a3..d991a1ce 100644
--- a/docs/render-pipeline.md
+++ b/docs/render-pipeline.md
@@ -492,11 +492,11 @@ Mirror ghostty 1.3.2 (`zig-pkg/ghostty-*/src/renderer/shadertoy.zig`,
   `crt.zig` is deleted. If the user insists on barrel in the bundled CRT, keep
   `crt.zig`'s inverse keyed to "bundled crt active".
 - **Compile** (decision 3): a user's file is compiled by spawning `glslc` with
-  the build's own invocation (`-fshader-stage=fragment <file> -o -`, SPIR-V on
-  stdout), on a thread of its own when the file joins the chain, never on the
+  the build's own flags, prefix and file on its stdin, SPIR-V on its stdout
+  (no file of ours anywhere; std's spawn allocates before fork), on a thread of its own when the file joins the chain, never on the
   frame path; the result is taken in at the next loop step. The prefix ends in
   `#line 1`, so glslc's errors count the file's own lines, and they name the
-  file, not the temporary source. A failed compile keeps the file's last good
+  file, not `<stdin>`. Level A redraws once a refresh of the window's display. A failed compile keeps the file's last good
   pipeline and says glslc's first line as a message; glslc missing is said
   once, and only files stay off (the bundled passes are compiled with the
   build, through the same prefix). No file watching: `Shader <path>` twice