hw/xwin: Register native screens with pseudoramiX

Update man page to document pseudo-xinerama

v2: Make the use of PseudoramiXExtensionInit() match the prototype
v3: Update for nonsdk_extinit.h

Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
Reviewed-by: Colin Harrison <colin.harrison@virgin.net>

hw/xwin/InitOutput.c

@@ -58,6 +58,11 @@ typedef WINAPI HRESULT(*SHGETFOLDERPATHPROC) (HWND hwndOwner,
                                               HANDLE hToken,
                                               DWORD dwFlags, LPTSTR pszPath);
 #endif
+
+#include "winmonitors.h"
+#include "nonsdk_extinit.h"
+#include "pseudoramiX/pseudoramiX.h"
+
 #include "glx_extinit.h"
 #ifdef XWIN_GLX_WINDOWS
 #include "glx/glwindows.h"
@@ -973,6 +978,59 @@ InitOutput(ScreenInfo * pScreenInfo, int argc, char *argv[])
         }
     }
 
+  /*
+     Unless full xinerama has been explicitly enabled, register all native screens with pseudoramiX
+  */
+  if (!noPanoramiXExtension)
+      noPseudoramiXExtension = TRUE;
+
+  if ((g_ScreenInfo[0].fMultipleMonitors) && !noPseudoramiXExtension)
+    {
+      int pass;
+
+      PseudoramiXExtensionInit();
+
+      /* Add primary monitor on pass 0, other monitors on pass 1, to ensure
+       the primary monitor is first in XINERAMA list */
+      for (pass = 0; pass < 2; pass++)
+        {
+          int iMonitor;
+
+          for (iMonitor = 1; ; iMonitor++)
+            {
+              struct GetMonitorInfoData data;
+              QueryMonitor(iMonitor, &data);
+              if (data.bMonitorSpecifiedExists)
+                {
+                  MONITORINFO mi;
+                  mi.cbSize = sizeof(MONITORINFO);
+
+                  if (GetMonitorInfo(data.monitorHandle, &mi))
+                    {
+                      /* pass == 1 XOR primary monitor flags is set */
+                      if ((!(pass == 1)) != (!(mi.dwFlags & MONITORINFOF_PRIMARY)))
+                        {
+                          /*
+                            Note the screen origin in a normalized coordinate space where (0,0) is at the top left
+                            of the native virtual desktop area
+                          */
+                          data.monitorOffsetX = data.monitorOffsetX - GetSystemMetrics(SM_XVIRTUALSCREEN);
+                          data.monitorOffsetY = data.monitorOffsetY - GetSystemMetrics(SM_YVIRTUALSCREEN);
+
+                          winDebug ("InitOutput - screen %d added at virtual desktop coordinate (%d,%d) (pseudoramiX) \n",
+                                    iMonitor-1, data.monitorOffsetX, data.monitorOffsetY);
+
+                          PseudoramiXAddScreen(data.monitorOffsetX, data.monitorOffsetY,
+                                               data.monitorWidth, data.monitorHeight);
+                        }
+                    }
+                }
+              else
+                break;
+            }
+        }
+    }
+
 #if defined(XWIN_CLIPBOARD) || defined(XWIN_MULTIWINDOW)
 
     /* Generate a cookie used by internal clients for authorization */

hw/xwin/man/XWin.man

@@ -76,6 +76,9 @@ preceeding \fB\-screen\fP parameter.
 .B \-[no]multimonitors or \-[no]multiplemonitors
 Create a screen 0 that covers all monitors [the primary monitor] on a system with
 multiple monitors.
+Fake XINERAMA data is created describing the individual monitors,
+(This is similar to the 'merged framebuffer' or 'pseudo-xinerama' mode provided by
+some drivers for the xorg X server).
 This option is currently enabled by default in \fB\-multiwindow\fP mode.
 .TP 8
 .B "\-screen \fIscreen_number\fP [\fIW\fP \fIH\fP [\fIX\fP \fIY\fP] | [[\fIW\fPx\fIH\fP[+\fIX\fP+\fIY\fP]][@\fIM\fP]] ] "