add TextScroll function for centering line to cursor, and use it in 'NormalFinish.centreToCursor' function

2025-09-13 18:23:55 +01:00
parent 18d2579605
commit 7a388f2983
2 changed files with 9 additions and 4 deletions
--- a/fcore/text-scroll.sml
+++ b/fcore/text-scroll.sml
@@ -34,7 +34,6 @@ struct
      (* cursorLine > prevLineNumber *)
      let
        val howManyLinesWeCanFit = windowHeight div TC.ySpace
-        val howManyLinesWeCanFit = howManyLinesWeCanFit
      in
        if cursorLine > prevLineNumber + (howManyLinesWeCanFit - 3) then
          (* cursorLine is after the visible part of the screen
@@ -43,4 +42,12 @@ struct
        else
          prevLineNumber
      end
+
+  fun getLineCentre (cursorLine, windowHeight) =
+    let
+      val howManyLinesWeCanFit = windowHeight div TC.ySpace
+      val startLine = cursorLine - (howManyLinesWeCanFit div 2)
+    in
+      Int.max (startLine, 0)
+    end
 end