From 580f8b2e1e9de5ded34649fbcd4e3c7b285f599c Mon Sep 17 00:00:00 2001
From: Basile Burg <basile.b@gmx.com>
Date: Tue, 31 Mar 2020 16:48:05 +0200
Subject: [PATCH] fix #11 - terminal scrollbar lacks of accuracy

---
 etc/terminal/terminalctrls.pas | 14 ++++++++------
 src/u_term.pas                 |  5 +++--
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/etc/terminal/terminalctrls.pas b/etc/terminal/terminalctrls.pas
index 22a7208d..fd74d24f 100644
--- a/etc/terminal/terminalctrls.pas
+++ b/etc/terminal/terminalctrls.pas
@@ -18,7 +18,7 @@ uses
 type
 
   TTerminalScrollInfo = record
-    min, max, value: integer;
+    min, max, value, pageSize: integer;
   end;
 
   TTerminalTextScrolled = procedure(sender: TObject; delta: integer) of Object;
@@ -634,16 +634,18 @@ end;
 function TTerminal.getVScrollInfo: TTerminalScrollInfo;
 {$ifdef hasgtk2term}
 var
-  a: PGtkAdjustment = nil;
+  a: PGtkAdjustment;
 {$endif}
 begin
+  FillChar(result, sizeOf(result), 0);
 {$ifdef hasgtk2term}
   if assigned(fTerminalHanlde) then
   begin
-    a            := vte_terminal_get_adjustment(fTerminalHanlde);
-    result.max   := round(a^.upper);
-    result.min   := round(a^.lower);
-    result.value := round(a^.value);
+    a               := vte_terminal_get_adjustment(fTerminalHanlde);
+    result.max      := round(a^.upper);
+    result.min      := round(a^.lower);
+    result.value    := round(a^.value);
+    result.pageSize := round(a^.page_size);
   end;
 {$endif}
 end;
diff --git a/src/u_term.pas b/src/u_term.pas
index 78331e1c..b93a2636 100644
--- a/src/u_term.pas
+++ b/src/u_term.pas
@@ -329,9 +329,10 @@ var
 begin
   if fDisableScrollBarSync or not visible or fTerm.isNil then
     exit;
-  i := fTerm.getVScrollInfo();
-  ScrollBar1.Max := i.max;
+  i                   := fTerm.getVScrollInfo();
+  ScrollBar1.Max      := i.max;
   ScrollBar1.Position := i.value;
+  ScrollBar1.PageSize := i.pageSize;
 end;
 
 procedure TTermWidget.FormShortCut(var Msg: TLMKey; var Handled: Boolean);