Fix T84501: Wintab button lag.

Multiple Wintab tablets do not send relative button state when
configured to do so. This causes button events to be delayed until
processed as Win32 button events.

This commit fixes the issue by configuring Wintab to use absolute
button state and tracking changes manually.

1 files changed, 6 insertions, 1 deletions

diff --git a/intern/ghost/intern/GHOST_SystemWin32.cpp b/intern/ghost/intern/GHOST_SystemWin32.cpp
index 181e3ad4014..5de97199fd8 100644
--- a/intern/ghost/intern/GHOST_SystemWin32.cpp
+++ b/intern/ghost/intern/GHOST_SystemWin32.cpp
@@ -1559,7 +1559,12 @@ LRESULT WINAPI GHOST_SystemWin32::s_wndProc(HWND hwnd, UINT msg, WPARAM wParam,
           break;
         case WT_PROXIMITY: {
           if (window->useTabletAPI(GHOST_kTabletWintab)) {
-            window->m_tabletInRange = LOWORD(lParam);
+            if (LOWORD(lParam)) {
+              window->m_tabletInRange = true;
+            }
+            else {
+              window->processWintabLeave();
+            }
           }
           eventHandled = true;
           break;