Link the renderer vtable from libgraphics on linux.

library/Core.cpp

@@ -869,7 +869,6 @@ bool Core::Init()
 
     // Init global object pointers
     df::global::InitGlobals();
-    init_screen_module(this);
 
     cerr << "Initializing Console.\n";
     // init the console.
@@ -895,6 +894,7 @@ bool Core::Init()
     */
     // initialize data defs
     virtual_identity::Init(this);
+    init_screen_module(this);
 
     // initialize common lua context
     Lua::Core::Init(con);

library/modules/Screen.cpp

@@ -55,6 +55,7 @@ using namespace DFHack;
 #include "df/item.h"
 #include "df/job.h"
 #include "df/building.h"
+#include "df/renderer.h"
 
 using namespace df::enums;
 using df::global::init;
@@ -312,6 +313,47 @@ class DFHACK_EXPORT enabler_inputst {
  public:
   std::string GetKeyDisplay(int binding);
 };
+
+class DFHACK_EXPORT renderer {
+    unsigned char *screen;
+    long *screentexpos;
+    char *screentexpos_addcolor;
+    unsigned char *screentexpos_grayscale;
+    unsigned char *screentexpos_cf;
+    unsigned char *screentexpos_cbr;
+    // For partial printing:
+    unsigned char *screen_old;
+    long *screentexpos_old;
+    char *screentexpos_addcolor_old;
+    unsigned char *screentexpos_grayscale_old;
+    unsigned char *screentexpos_cf_old;
+    unsigned char *screentexpos_cbr_old;
+public:
+    virtual void update_tile(int x, int y) {};
+    virtual void update_all() {};
+    virtual void render() {};
+    virtual void set_fullscreen();
+    virtual void zoom(df::zoom_commands cmd);
+    virtual void resize(int w, int h) {};
+    virtual void grid_resize(int w, int h) {};
+    renderer() {
+        screen = NULL;
+        screentexpos = NULL;
+        screentexpos_addcolor = NULL;
+        screentexpos_grayscale = NULL;
+        screentexpos_cf = NULL;
+        screentexpos_cbr = NULL;
+        screen_old = NULL;
+        screentexpos_old = NULL;
+        screentexpos_addcolor_old = NULL;
+        screentexpos_grayscale_old = NULL;
+        screentexpos_cf_old = NULL;
+        screentexpos_cbr_old = NULL;
+    }
+    virtual ~renderer();
+    virtual bool get_mouse_coords(int &x, int &y) { return false; }
+    virtual bool uses_opengl();
+};
 #else
 struct less_sz {
   bool operator() (const string &a, const string &b) const {
@@ -326,7 +368,9 @@ static std::map<df::interface_key,std::set<string,less_sz> > *keydisplay = NULL;
 void init_screen_module(Core *core)
 {
 #ifdef _LINUX
-    core = core;
+    renderer tmp;
+    if (!strict_virtual_cast<df::renderer>((virtual_ptr)&tmp))
+        cerr << "Could not fetch the renderer vtable." << std::endl;
 #else
     if (!core->vinfo->getAddress("keydisplay", keydisplay))
         keydisplay = NULL;

library/xml

@@ -1 +1 @@
-Subproject commit 4bfc5b197de9ca096a11b9c1594e043bd8ae707a
+Subproject commit 378f91d0964e09e3cfa0ecbea100ef2cc12a59ab

plugins/dfstream.cpp

@@ -148,19 +148,19 @@ class renderer_decorator : public df::renderer {
     client_pool clients;
 
     // The following three methods facilitate copying of state to the inner object
-    void set_inner_to_null() {
-        inner->screen = NULL;
-        inner->screentexpos = NULL;
-        inner->screentexpos_addcolor = NULL;
-        inner->screentexpos_grayscale = NULL;
-        inner->screentexpos_cf = NULL;
-        inner->screentexpos_cbr = NULL;
-        inner->screen_old = NULL;
-        inner->screentexpos_old = NULL;
-        inner->screentexpos_addcolor_old = NULL;
-        inner->screentexpos_grayscale_old = NULL;
-        inner->screentexpos_cf_old = NULL;
-        inner->screentexpos_cbr_old = NULL;
+    void set_to_null() {
+        screen = NULL;
+        screentexpos = NULL;
+        screentexpos_addcolor = NULL;
+        screentexpos_grayscale = NULL;
+        screentexpos_cf = NULL;
+        screentexpos_cbr = NULL;
+        screen_old = NULL;
+        screentexpos_old = NULL;
+        screentexpos_addcolor_old = NULL;
+        screentexpos_grayscale_old = NULL;
+        screentexpos_cf_old = NULL;
+        screentexpos_cbr_old = NULL;
     }
 
     void copy_from_inner() {
@@ -259,9 +259,12 @@ public:
     }
     virtual ~renderer_decorator() {
         *alive = false;
-        if (inner) set_inner_to_null();
-        delete inner;
-        inner = 0;
+        if (inner) {
+            copy_to_inner();
+            delete inner;
+            inner = 0;
+        }
+        set_to_null();
     }
     virtual bool get_mouse_coords(int *x, int *y) { return inner->get_mouse_coords(x, y); }
     virtual bool uses_opengl() { return inner->uses_opengl(); }
@@ -336,6 +339,11 @@ auto_renderer_decorator decorator;
 
 DFhackCExport command_result plugin_init ( color_ostream &out, vector <PluginCommand> &commands)
 {
+    if (!df::renderer::_identity.can_allocate())
+    {
+        out.printerr("Cannot allocate a renderer\n");
+        return CR_OK;
+    }
     if (!decorator) {
         decorator = renderer_decorator::hook(active_renderer(), &decorator.alive);
     }
@@ -344,6 +352,10 @@ DFhackCExport command_result plugin_init ( color_ostream &out, vector <PluginCom
 
 DFhackCExport command_result plugin_shutdown ( color_ostream &out )
 {
+    if (decorator && active_renderer() == decorator.get())
+    {
+        renderer_decorator::unhook(active_renderer(), decorator.get(), out);
+    }
     decorator.reset();
     return CR_OK;
 }