https://git.reactos.org/?p=reactos.git;a=commitdiff;h=3bf7e3ac13c5c9df373827c102b763b5b9822204
commit 3bf7e3ac13c5c9df373827c102b763b5b9822204 Author: Doug Lyons <[email protected]> AuthorDate: Sun Sep 12 15:54:46 2021 -0500 Commit: GitHub <[email protected]> CommitDate: Sun Sep 12 22:54:46 2021 +0200 [NTUSER] Improve Themed Scrollbars by Minimizing Updates (#3953) This fixes regressions CORE-17754 and CORE-17755 which regressed by 0.4.15-dev-3086-g 236649c626f97c68a9d0a6709a1bb342681b2aa0 --- win32ss/user/ntuser/scrollbar.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/win32ss/user/ntuser/scrollbar.c b/win32ss/user/ntuser/scrollbar.c index 359bc923f5b..52d5f38c377 100644 --- a/win32ss/user/ntuser/scrollbar.c +++ b/win32ss/user/ntuser/scrollbar.c @@ -488,10 +488,13 @@ co_IntSetScrollInfo(PWND Window, INT nBar, LPCSCROLLINFO lpsi, BOOL bRedraw) UINT new_flags; INT action = 0; PSBDATA pSBData; - DWORD OldPos = 0; + DWORD OldPos = 0, CurrentPos = 0; BOOL bChangeParams = FALSE; /* Don't show/hide scrollbar if params don't change */ UINT MaxPage; int MaxPos; + /* [0] = HORZ, [1] = VERT */ + static PWND PrevHwnd[2] = { 0 }; + static DWORD PrevPos[2] = { 0 }; ASSERT_REFS_CO(Window); @@ -686,7 +689,14 @@ co_IntSetScrollInfo(PWND Window, INT nBar, LPCSCROLLINFO lpsi, BOOL bRedraw) UpdateRect.bottom -= psbi->dxyLineButton; } } - co_UserRedrawWindow(Window, &UpdateRect, 0, RDW_INVALIDATE | RDW_FRAME); + CurrentPos = lpsi->fMask & SIF_PREVIOUSPOS ? OldPos : pSBData->pos; + /* Check for changes to Window or CurrentPos */ + if ((Window != PrevHwnd[nBar]) || (CurrentPos != PrevPos[nBar])) + { + co_UserRedrawWindow(Window, &UpdateRect, 0, RDW_INVALIDATE | RDW_FRAME); + PrevHwnd[nBar] = Window; + PrevPos[nBar] = CurrentPos; + } } } // FIXME: Arrows /* else if( action & SA_SSI_REPAINT_ARROWS )
