Patch [#26799] embedded blenderplayer not receiving keyboard input by Sebastian Korczak

(patch co-reviewed by Nathan Letwory)

Overview: GHOST using rawinput for keyboard input. GHOST window receives WM_INPUT only when it is the active window. Child window cannot be active, so when embedding blenderplayer, WM_INPUT is consumed by top level parent window (for Burster it is the web browser window). Patch register raw input device as 'inputsink' - it makes GHOST window receives all keyboard messages. Window procedure check if GHOST window is active or focused.

::TranslateMessage(&msg) generates WM_CHAR etc. messages from WM_KEYDOWN, WM_KEYUP etc. Because of using RawInput only WM_INPUT messages are processed, so we doesn't need WM_CHAR, WM_KEYDOWN etc. [this is why ::TranslateMessage is no longer getting called].

Note: It's responsibility of the parent window (aka the wrapper) to send WM_SETFOCUS to child window (embedded blenderplayer).
However some parent windows (e.g. webbrowsers) will not send WM_SETFOCUS to the child window when someone clicks on it.
In those cases the blenderplayer needs to be patched to call setFocus(&msg); in the event of WM_LBUTTONDOWN (see GHOST_SystemWin32.cpp)

2 files changed, 14 insertions, 1 deletions

diff --git a/intern/ghost/intern/GHOST_SystemWin32.cpp b/intern/ghost/intern/GHOST_SystemWin32.cpp
index 2fdddda835d..455a166ece0 100644
--- a/intern/ghost/intern/GHOST_SystemWin32.cpp
+++ b/intern/ghost/intern/GHOST_SystemWin32.cpp
@@ -304,7 +304,6 @@ bool GHOST_SystemWin32::processEvents(bool waitForEvent)
 
 		// Process all the events waiting for us
 		while (::PeekMessage(&msg, 0, 0, 0, PM_REMOVE) != 0) {
-			::TranslateMessage(&msg);
 			::DispatchMessage(&msg);
 			anyProcessed = true;
 		}
@@ -819,6 +818,11 @@ LRESULT WINAPI GHOST_SystemWin32::s_wndProc(HWND hwnd, UINT msg, WPARAM wParam,
 				// Keyboard events, processed
 				////////////////////////////////////////////////////////////////////////
 				case WM_INPUT:
+					// check WM_INPUT from input sink when ghost window is not in the foreground
+					if (wParam == RIM_INPUTSINK) {
+						if (GetFocus() != hwnd) // WM_INPUT message not for this window
+							return 0;
+					} //else wPAram == RIM_INPUT
 					event = processKeyEvent(window, wParam, lParam);
 					if (!event) {
 						GHOST_PRINT("GHOST_SystemWin32::wndProc: key event ")
diff --git a/intern/ghost/intern/GHOST_WindowWin32.cpp b/intern/ghost/intern/GHOST_WindowWin32.cpp
index a89b2608bb4..aae1509fda1 100644
--- a/intern/ghost/intern/GHOST_WindowWin32.cpp
+++ b/intern/ghost/intern/GHOST_WindowWin32.cpp
@@ -307,6 +307,15 @@ GHOST_WindowWin32::GHOST_WindowWin32(
 		}
 	}
 
+	if (parentwindowhwnd != 0) {
+		RAWINPUTDEVICE device = {0};
+		device.usUsagePage	= 0x01; /* usUsagePage & usUsage for keyboard*/
+		device.usUsage		= 0x06; /* http://msdn.microsoft.com/en-us/windows/hardware/gg487473.aspx */
+		device.dwFlags |= RIDEV_INPUTSINK; // makes WM_INPUT is visible for ghost when has parent window
+		device.hwndTarget = m_hWnd;
+		RegisterRawInputDevices(&device, 1, sizeof(device));
+	}
+
 	m_wintab = ::LoadLibrary("Wintab32.dll");
 	if (m_wintab) {
 		GHOST_WIN32_WTInfo fpWTInfo = ( GHOST_WIN32_WTInfo ) ::GetProcAddress( m_wintab, "WTInfoA" );