scroll automap content with the mouse (proof of concept)

Fixes #1729

src/am_map.c

@@ -28,6 +28,7 @@
 #include "doomdef.h"
 #include "doomstat.h"
 #include "doomtype.h"
+#include "g_input.h"
 #include "hu_stuff.h"
 #include "i_video.h"
 #include "m_config.h"
@@ -128,6 +129,8 @@ static int m_zoomin_mouse = M2_ZOOMIN;
 static int m_zoomout_mouse = M2_ZOOMOUT;
 static boolean mousewheelzoom;
 
+static boolean scrollmode;
+
 // translates between frame-buffer and map distances
 // [FG] fix int overflow that causes map and grid lines to disappear
 #define FTOM(x) ((((int64_t)(x)<<16)*scale_ftom)>>16)
@@ -485,6 +488,12 @@ static void AM_changeWindowLoc(void)
     incy = m_paninc.y;
   }
 
+  if (scrollmode)
+  {
+    m_paninc.x = 0;
+    m_paninc.y = 0;
+  }
+
   if (automaprotate)
   {
     AM_rotate(&incx, &incy, ANGLE_MAX - mapangle);
@@ -916,6 +925,10 @@ boolean AM_Responder
       automaprotate = !automaprotate;
       togglemsg("%s", automaprotate ? s_AMSTR_ROTATEON : s_AMSTR_ROTATEOFF);
     }
+    else if (M_InputActivated(input_strafe))
+    {
+      scrollmode = true;
+    }
     else
     {
       rc = false;
@@ -955,11 +968,25 @@ boolean AM_Responder
     {
       buttons_state[ZOOM_IN] = 0;
     }
+    else if (M_InputDeactivated(input_strafe))
+    {
+      scrollmode = false;
+    }
   }
 
   m_paninc.x = 0;
   m_paninc.y = 0;
 
+  if (scrollmode)
+  {
+    if (ev->type == ev_mouse)
+    {
+      m_paninc.x -= (int)G_CalcMouseSide(ev->data1) * MAPUNIT;
+      m_paninc.y += (int)G_CalcMouseVert(ev->data2) * MAPUNIT;
+      rc = true;
+    }
+  }
+
   if (!followplayer)
   {
     int scaled_f_paninc = (f_paninc * video.xscale) >> FRACBITS;