Add new follow plugin that makes the DF window center on and follow a selected unit.

plugins/CMakeLists.txt

@@ -76,6 +76,7 @@ DFHACK_PLUGIN(workflow workflow.cpp)
 DFHACK_PLUGIN(showmood showmood.cpp)
 DFHACK_PLUGIN(fixveins fixveins.cpp)
 DFHACK_PLUGIN(fixpositions fixpositions.cpp)
+DFHACK_PLUGIN(follow follow.cpp)
 #DFHACK_PLUGIN(versionosd versionosd.cpp)
 
 # this is the skeleton plugin. If you want to make your own, make a copy and then change it

plugins/follow.cpp

@@ -0,0 +1,128 @@
+// Make the camera follow the selected unit
+
+#include "Core.h"
+#include <Console.h>
+#include <Export.h>
+#include <PluginManager.h>
+
+#include "DFHack.h"
+#include "DataDefs.h"
+#include "modules/Gui.h"
+#include "modules/World.h"
+#include "modules/Maps.h"
+#include <df/unit.h>
+#include <df/creature_raw.h>
+
+using namespace DFHack;
+using namespace df::enums;
+
+
+command_result follow (Core * c, std::vector <std::string> & parameters);
+
+df::unit *followedUnit;
+int32_t prevX, prevY, prevZ;
+
+DFhackCExport const char * plugin_name ( void )
+{
+    return "follow";
+}
+
+
+DFhackCExport command_result plugin_init ( Core * c, std::vector <PluginCommand> &commands)
+{
+    commands.clear();
+    commands.push_back(PluginCommand(
+        "follow", "Follow the selected unit until camera control is released",
+        follow, false, 
+        "  Select a unit and run this plugin to make the camera follow it. Moving the camera yourself deactivates the plugin.\n"
+    ));
+    followedUnit = 0;
+    prevX=prevY=prevZ = -1;
+    return CR_OK;
+}
+
+
+DFhackCExport command_result plugin_shutdown ( Core * c )
+{
+    return CR_OK;
+}
+
+// Called to notify the plugin about important state changes.
+// Invoked with DF suspended, and always before the matching plugin_onupdate.
+// More event codes may be added in the future.
+
+DFhackCExport command_result plugin_onstatechange(Core* c, state_change_event event)
+{
+    switch (event) {
+    case SC_GAME_LOADED:
+    case SC_GAME_UNLOADED:
+        followedUnit = 0;
+        prevX=prevY=prevZ = -1;
+        break;
+    default:
+        break;
+    }
+    return CR_OK;
+}
+
+
+DFhackCExport command_result plugin_onupdate ( Core * c )
+{
+    if (!followedUnit) return CR_OK;
+    DFHack::World *world =c->getWorld();
+    if (world->ReadPauseState() && prevX==-1) return CR_OK;
+    Gui *gui = c->getGui();
+    df::coord &unitPos = followedUnit->pos;
+    int32_t x,y,z,w,h;
+    gui->getViewCoords(x,y,z);
+    gui->getWindowSize(w,h);
+    if (prevX==-1)
+    {
+        prevX = x;
+        prevY = y;
+        prevZ = z;
+    }
+    else if(prevX != x || prevY != y || prevZ != z)
+    {
+        followedUnit = 0;
+        prevX=prevY=prevZ = -1;
+        c->con.print("No longer following anything.\n");
+        return CR_OK;
+    }
+    
+    uint32_t x_max, y_max, z_max;
+    Simple::Maps::getSize(x_max, y_max, z_max);
+
+    x_max *= 16;
+    y_max *= 16;
+
+    prevX = unitPos.x + w/2 >= x_max ? x_max-w+2 : (unitPos.x >= w/2 ? unitPos.x - w/2 : 0);
+    prevY = unitPos.y + h/2 >= y_max ? y_max-h+2 : (unitPos.y >= h/2 ? unitPos.y - h/2 : 0);
+    prevZ = unitPos.z;
+
+    gui->setViewCoords(prevX, prevY, prevZ);
+    
+    return CR_OK;
+}
+
+command_result follow (Core * c, std::vector <std::string> & parameters)
+{
+    if (!parameters.empty())
+        return CR_WRONG_USAGE;
+
+    CoreSuspender suspend(c);
+
+    followedUnit = getSelectedUnit(c);
+    if (followedUnit)
+    {
+        c->con.print("Unpause to begin following ");
+        c->con.print(df::global::world->raws.creatures.all[followedUnit->race]->name[0].c_str());
+        if (followedUnit->name.has_name)
+        {
+            c->con.print(" %s", followedUnit->name.first_name.c_str());
+        }
+        c->con.print(".\n");
+    }
+    else followedUnit = 0;
+    return CR_OK;
+}