From e602e36495700549c395e4b9a7f462c1fd50674f Mon Sep 17 00:00:00 2001
From: rr- <rr-@sakuya.pl>
Date: Mon, 29 Mar 2021 18:04:05 +0200
Subject: [PATCH] deactivate game when alt-tabbed (fixes #1)

---
 src/global/vars.c       |  1 +
 src/global/vars.h       |  1 +
 src/specific/frontend.c |  7 +++---
 src/specific/smain.c    | 47 +++++++++++++++++++++++++++++++++++------
 4 files changed, 46 insertions(+), 10 deletions(-)

diff --git a/src/global/vars.c b/src/global/vars.c
index d12663269..e44927e18 100644
--- a/src/global/vars.c
+++ b/src/global/vars.c
@@ -28,6 +28,7 @@ void (*EffectRoutines[])(ITEM_INFO *item) = {
     ChainBlock, Flicker,
 };
 
+int8_t IsGameWindowActive = 1;
 int32_t NoInputCount = 0;
 int32_t IDelay;
 int32_t IDCount;
diff --git a/src/global/vars.h b/src/global/vars.h
index 341a1f7fa..92c0ae734 100644
--- a/src/global/vars.h
+++ b/src/global/vars.h
@@ -196,6 +196,7 @@ extern KEYSTUFF* KeyData;
 extern char *ATIUserSettingsPath;
 extern char *T1MUserSettingsPath;
 
+extern int8_t IsGameWindowActive;
 extern double UITextScale;
 extern double UIBarScale;
 
diff --git a/src/specific/frontend.c b/src/specific/frontend.c
index 3f0443a7b..02ee00841 100644
--- a/src/specific/frontend.c
+++ b/src/specific/frontend.c
@@ -15,6 +15,7 @@
 #include "specific/smain.h"
 #include "util.h"
 
+#include <dinput.h>
 #include <stdlib.h>
 
 const char *FMVPaths[] = {
@@ -186,13 +187,13 @@ int32_t WinPlayFMV(int32_t sequence, int32_t mode)
         WinSpinMessageLoop();
 
         if (T1MConfig.fix_fmv_esc_key) {
-            if (KeyData->keymap[1]) {
+            if (KeyData->keymap[DIK_ESCAPE]) {
                 keypress = 1;
-            } else if (keypress && !KeyData->keymap[1]) {
+            } else if (keypress && !KeyData->keymap[DIK_ESCAPE]) {
                 break;
             }
         } else {
-            if (KeyData->keymap[1]) {
+            if (KeyData->keymap[DIK_ESCAPE]) {
                 break;
             }
         }
diff --git a/src/specific/smain.c b/src/specific/smain.c
index 0a7684a3d..53d2a7e0d 100644
--- a/src/specific/smain.c
+++ b/src/specific/smain.c
@@ -50,14 +50,16 @@ void ShowFatalError(const char *message)
 int32_t WinSpinMessageLoop()
 {
     MSG msg;
-    while (PeekMessageA(&msg, 0, 0, 0, PM_NOREMOVE)) {
-        if (!GetMessageA(&msg, 0, 0, 0)) {
-            TerminateGame(0);
+    do {
+        while (PeekMessageA(&msg, 0, 0, 0, PM_NOREMOVE)) {
+            if (!GetMessageA(&msg, 0, 0, 0)) {
+                TerminateGame(0);
+            }
+
+            TranslateMessage(&msg);
+            DispatchMessageA(&msg);
         }
-
-        TranslateMessage(&msg);
-        DispatchMessageA(&msg);
-    }
+    } while (!IsGameWindowActive);
 
     int32_t time_ms = timeGetTime();
     int32_t old_ticks = Ticks;
@@ -113,20 +115,48 @@ static LRESULT WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
     case WM_CLOSE:
         DestroyWindow(TombHWND);
         return 0;
+
     case WM_DESTROY:
         PostQuitMessage(0);
         return 0;
+
     case WM_SIZE:
         return 1;
+
     case WM_MOVE:
         return 0;
+
     case WM_SETCURSOR:
         SetCursor(0);
         return 1;
+
     case WM_ERASEBKGND:
         return 1;
+
+    case WM_ACTIVATEAPP:
+        // mute the music when the game is not active
+        if (wParam && !IsGameWindowActive) {
+            if (OptionMusicVolume) {
+                S_MusicVolume(OptionMusicVolume * 25 + 5);
+            } else {
+                S_MusicVolume(0);
+            }
+        } else if (!wParam && IsGameWindowActive) {
+            S_MusicVolume(0);
+        }
+        if (wParam && !IsGameWindowActive) {
+            // TODO: remove this after switching to DInput
+            for (int i = 0; i < 256; i++) {
+                KeyData->keymap[i] = 0;
+            }
+            KeyData->keys_held = 0;
+        }
+        IsGameWindowActive = wParam != 0;
+        return 1;
+
     case WM_NCPAINT:
         return 0;
+
     case WM_GETMINMAXINFO: {
         MINMAXINFO *min_max_info = (MINMAXINFO *)lParam;
         min_max_info->ptMinTrackSize.x = DDrawSurfaceWidth;
@@ -136,12 +166,15 @@ static LRESULT WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
         return DefWindowProcA(
             hWnd, WM_GETMINMAXINFO, wParam, (LPARAM)min_max_info);
     }
+
     case WM_MOVING:
         GetWindowRect(TombHWND, (LPRECT)lParam);
         return 1;
+
     case MM_MCINOTIFY:
         MusicPlayLooped();
         return 0;
+
     default:
         return DefWindowProcA(hWnd, uMsg, wParam, lParam);
     }