Enable custom window control buttons

cmd/vrc_osc_gui/window_windows.go

@@ -140,6 +140,7 @@ var hwndNoZOrder uintptr = 0x0004
 var hwndNoSize uintptr = 0x0001
 var hwndNoActivate uintptr = 0x0010
 var hwndShowWindow uintptr = 0x0040
+var swMinimize uintptr = 6
 var swRestore uintptr = 9
 var swHideControl uintptr = 0
 var swShowControl uintptr = 5
@@ -794,8 +795,25 @@ func runNativeGUI(initialTab string) error {
 						width = rc.Right
 					}
 				}
-				if x >= width-42 && x <= width-22 && y >= 12 && y <= 32 {
-					guiLog("close button ignored to keep GUI visible")
+				switch {
+				case pointInHeaderDot(x, y, width-92, 22):
+					guiLog("window control minimize")
+					if showWindowProc != nil {
+						showWindowProc.Call(hwnd, swMinimize)
+					}
+					return 0
+				case pointInHeaderDot(x, y, width-62, 22):
+					guiLog("window control topmost toggle")
+					app.topMost = !app.topMost
+					saveGUISettings(&app)
+					applyTopMost(hwnd, &app)
+					if invalidateRectProc != nil {
+						invalidateRectProc.Call(hwnd, 0, 1)
+					}
+					return 0
+				case pointInHeaderDot(x, y, width-32, 22):
+					guiLog("window control close")
+					postQuitMessage.Call(0)
 					return 0
 				}
 				releaseCapture.Call()
@@ -898,7 +916,8 @@ func runNativeGUI(initialTab string) error {
 			postQuitMessage.Call(0)
 			return 0
 		case wmCloseGUI:
-			guiLog("wmClose ignored to keep GUI visible")
+			guiLog("wmClose received")
+			postQuitMessage.Call(0)
 			return 0
 		}
 		ret, _, _ := defWindowProc.Call(hwnd, uintptr(message), wParam, lParam)
@@ -1732,6 +1751,10 @@ func paintMainWindow(hwnd uintptr, app *guiApp) uintptr {
 	return 0
 }
 
+func pointInHeaderDot(x, y, cx, cy int32) bool {
+	return x >= cx-11 && x <= cx+11 && y >= cy-11 && y <= cy+11
+}
+
 func paintFooter(hdc uintptr, rc winRect, app *guiApp) {
 	if app == nil {
 		return