dinput: use buffered polling

Short keyboard and mouse events won't get dropped. We
can now decrease the poll interval from 250 Hz to 10Hz.

1 files changed, 73 insertions, 43 deletions

diff --git a/dinput/keybinding-worker.cpp b/dinput/keybinding-worker.cpp
index e0d09909..468ef477 100644
--- a/dinput/keybinding-worker.cpp
+++ b/dinput/keybinding-worker.cpp
@@ -8,13 +8,15 @@
 
 #ifdef _WIN32
 
-#include "keybinding-worker.hpp"
+#include "compat/sleep.hpp"
 #include "compat/util.hpp"
-#include <functional>
-#include <windows.h>
+#include "keybinding-worker.hpp"
+
 #include <QDebug>
 #include <QMutexLocker>
 
+#include <windows.h>
+
 Key::Key() {}
 
 bool Key::should_process()
@@ -65,6 +67,22 @@ bool KeybindingWorker::init()
         return false;
     }
 
+    {
+        DIPROPDWORD dipdw;
+        dipdw.dwData = 128;
+        dipdw.diph.dwHeaderSize = sizeof(dipdw.diph);
+        dipdw.diph.dwHow = DIPH_DEVICE;
+        dipdw.diph.dwObj = 0;
+        dipdw.diph.dwSize = sizeof(dipdw);
+        if ( dinkeyboard->SetProperty(DIPROP_BUFFERSIZE, &dipdw.diph) != DI_OK)
+        {
+            qDebug() << "setup keyboard buffer mode failed!";
+            dinkeyboard->Release();
+            dinkeyboard = 0;
+            return false;
+        }
+    }
+
     if (dinkeyboard->Acquire() != DI_OK)
     {
         dinkeyboard->Release();
@@ -90,9 +108,6 @@ KeybindingWorker& KeybindingWorker::make()
 
 void KeybindingWorker::run()
 {
-    unsigned char keystate[256] = {0};
-    unsigned char old_keystate[256] = {0};
-
     while (!isInterruptionRequested())
     {
         {
@@ -100,21 +115,69 @@ void KeybindingWorker::run()
 
             if (receivers.size())
             {
+                /* There are some problems reported on various forums
+                 * with regard to key-up events. But that's what I dug up:
+                 *
+                 * https://www.gamedev.net/forums/topic/633011-keyboard-getdevicedata-buffered-never-releases-keys/
+                 *
+                 * "Over in the xna forums (http://xboxforums.create.msdn.com/forums/p/108722/642144.aspx#642144)
+                 *  we discovered this behavior is caused by calling Unacquire in your event processing loop.
+                 *  Funnily enough only the keyboard seems to be affected."
+                 *
+                 * Key-up events work on my end.
+                 */
+
                 {
-                    const HRESULT hr = dinkeyboard->GetDeviceState(256, (LPVOID)keystate);
+                    DWORD sz = num_keyboard_states;
+                    const HRESULT hr = dinkeyboard->GetDeviceData(sizeof(*keyboard_states), keyboard_states, &sz, 0);
 
                     if (hr != DI_OK)
                     {
-                        qDebug() << "Tracker::run GetDeviceState function failed!" << GetLastError();
+                        qDebug() << "Tracker::run GetDeviceData function failed!" << hr;
                         Sleep(25);
                         continue;
                     }
+                    else
+                    {
+                        for (unsigned k = 0; k < sz; k++)
+                        {
+                            const unsigned idx = keyboard_states[k].dwOfs & 0xff; // defensive programming
+                            const bool held = !!(keyboard_states[k].dwData & 0x80);
+
+                            switch (idx)
+                            {
+                            case DIK_LCONTROL:
+                            case DIK_LSHIFT:
+                            case DIK_LALT:
+                            case DIK_RCONTROL:
+                            case DIK_RSHIFT:
+                            case DIK_RALT:
+                            case DIK_LWIN:
+                            case DIK_RWIN:
+                                break;
+                            default:
+                            {
+                                Key k;
+                                k.shift = !!((keystate[DIK_LSHIFT] & 0x80) | (keystate[DIK_RSHIFT] & 0x80));
+                                k.alt = !!((keystate[DIK_LALT] & 0x80) | (keystate[DIK_RALT] & 0x80));
+                                k.ctrl = !!((keystate[DIK_LCONTROL] & 0x80) | (keystate[DIK_RCONTROL] & 0x80));
+                                k.keycode = idx;
+                                k.held = held;
+
+                                for (auto& r : receivers)
+                                    (*r)(k);
+                                break;
+                            }
+                            }
+                            keystate[idx] = held;
+                        }
+                    }
                 }
 
                 {
                     using joy_fn = std::function<void(const QString& guid, int idx, bool held)>;
 
-                    joy_fn f = [&](const QString& guid, int idx, bool held) -> void {
+                    joy_fn f = [&](const QString& guid, int idx, bool held) {
                         Key k;
                         k.keycode = idx;
                         k.shift = !!(keystate[DIK_LSHIFT] & 0x80 || keystate[DIK_RSHIFT] & 0x80);
@@ -129,43 +192,10 @@ void KeybindingWorker::run()
 
                     joy_ctx.poll(f);
                 }
-
-                for (int i = 0; i < 256; i++)
-                {
-                    Key k;
-                    if (old_keystate[i] != keystate[i])
-                    {
-                        const bool held = !!(keystate[i] & 0x80);
-                        switch (i)
-                        {
-                        case DIK_LCONTROL:
-                        case DIK_LSHIFT:
-                        case DIK_LALT:
-                        case DIK_RCONTROL:
-                        case DIK_RSHIFT:
-                        case DIK_RALT:
-                        case DIK_LWIN:
-                        case DIK_RWIN:
-                            break;
-                        default:
-                            k.shift = !!((keystate[DIK_LSHIFT] & 0x80) || (keystate[DIK_RSHIFT] & 0x80));
-                            k.alt = !!((keystate[DIK_LALT] & 0x80) || (keystate[DIK_RALT] & 0x80));
-                            k.ctrl = !!((keystate[DIK_LCONTROL] & 0x80) || (keystate[DIK_RCONTROL] & 0x80));
-                            k.keycode = i;
-                            k.held = held;
-
-                            for (auto& r : receivers)
-                                (*r)(k);
-                            break;
-                        }
-                    }
-                    old_keystate[i] = keystate[i];
-                }
             }
         }
 
-        // keypresses get dropped with high values
-        Sleep(4);
+        portable::sleep(100);
     }
 }