From 6e7dcd7865217698808883762c4609ff6a749038 Mon Sep 17 00:00:00 2001
From: Dan Rasmuson <danrasmuson@gmail.com>
Date: Mon, 25 May 2026 10:27:17 -0500
Subject: [PATCH] mode/document: Add scroll-half-page-{up,down} (C-d/C-u in
 vi-normal)
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Vim users expect C-d and C-u to scroll by half a viewport. Nyxt
already ships scroll-page-{up,down} and scroll-to-{top,bottom},
but no half-page variant, so the vi-normal keyscheme leaves C-d
and C-u unbound.

Add scroll-half-page-down and scroll-half-page-up as small wrappers
around window.scrollBy(0, ±innerHeight/2), and bind them to C-d /
C-u in the document-mode vi-normal keyscheme alongside the existing
scroll-page-{up,down} bindings.
---
 source/mode/document.lisp | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/source/mode/document.lisp b/source/mode/document.lisp
index 72c5ab47128..58ff194a9d1 100644
--- a/source/mode/document.lisp
+++ b/source/mode/document.lisp
@@ -110,7 +110,9 @@ Important pieces of functionality are:
        "pageup" 'scroll-page-up
        "C-f" 'scroll-page-down
        "space" 'scroll-page-down
-       "pagedown" 'scroll-page-down)))))
+       "pagedown" 'scroll-page-down
+       "C-d" 'scroll-half-page-down
+       "C-u" 'scroll-half-page-up)))))
 
 (define-configuration document-buffer
   ((default-modes (cons 'document-mode %slot-value%))))
@@ -295,6 +297,14 @@ The amount scrolled is determined by the buffer's `horizontal-scroll-distance'."
   (ps-eval (ps:chain window (scroll-by 0 (- (* (ps:lisp (page-scroll-ratio (current-buffer)))
                                              (ps:@ window inner-height)))))))
 
+(define-command scroll-half-page-down ()
+  "Scroll down by half a page height."
+  (ps-eval (ps:chain window (scroll-by 0 (/ (ps:@ window inner-height) 2)))))
+
+(define-command scroll-half-page-up ()
+  "Scroll up by half a page height."
+  (ps-eval (ps:chain window (scroll-by 0 (- (/ (ps:@ window inner-height) 2))))))
+
 (define-command zoom-page (&key (buffer (current-buffer)))
   "Zoom in the current buffer."
   (incf (ffi-buffer-zoom-ratio buffer) (zoom-ratio-step buffer)))