Prototype of Drone object.

drone.c

@@ -0,0 +1,123 @@
+#include "scriptmine.h"
+
+duk_ret_t drone_box(duk_context *ctx)
+{
+ duk_push_this(ctx); // [b w h d this]
+ duk_get_prop_string(ctx, -1, "x");
+ int x = duk_to_int(ctx, -1);
+ duk_remove(ctx, -1);
+ duk_get_prop_string(ctx, -1, "y");
+ int y = duk_to_int(ctx, -1);
+ duk_remove(ctx, -1);
+ duk_get_prop_string(ctx, -1, "z");
+ int z = duk_to_int(ctx, -1);
+ duk_remove(ctx, -1);
+ int blockID = duk_to_int(ctx, -5);
+ const char *nodeName = blockID_to_node_name(blockID);
+ lua_getfield(Lg, LUA_GLOBALSINDEX, "minetest");  // [minetest]
+ lua_getfield(Lg, -1, "set_node");  // [minetest get_player_by_name]
+ lua_remove(Lg, -2);  // [get_player_by_name]
+	lua_newtable(Lg);
+	lua_pushnumber(Lg, x);
+	lua_setfield(Lg, -2, "x");
+	lua_pushnumber(Lg, y);
+	lua_setfield(Lg, -2, "y");
+	lua_pushnumber(Lg, z);
+	lua_setfield(Lg, -2, "z");
+	lua_newtable(Lg);
+	lua_pushstring(Lg, nodeName);
+	lua_setfield(Lg, -2, "name");
+ lua_call(Lg, 2, 0);
+ return 0;
+}
+
+duk_ret_t drone_constructor(duk_context *ctx)
+{
+ if (!duk_is_constructor_call(ctx))
+ {
+  return DUK_RET_TYPE_ERROR;
+ }
+
+ lua_getfield(Lg, LUA_GLOBALSINDEX, "minetest");  // [minetest]
+ lua_getfield(Lg, -1, "get_player_by_name");  // [minetest get_player_by_name]
+ lua_remove(Lg, -2);  // [get_player_by_name]
+ lua_pushstring(Lg, name);  // [get_player_by_name name]
+ lua_call(Lg, 1, 1);  // [player]
+ lua_getmetatable(Lg, -1);  // [player metatable]
+ lua_pushstring(Lg, "__index");  // [player metatable __index]
+ lua_rawget(Lg, -2);  // [player metatable __index]
+ lua_pushstring(Lg, "getpos");  // [player metatable __index getpos]
+ lua_rawget(Lg, -2);  // [player metatable __index getpos]
+ lua_pushvalue(Lg, -4);  // [player metatable __index getpos player] 
+ lua_call(Lg, 1, 1); // [player metatable __index postable]
+ lua_getfield(Lg, -1, "x");
+ int x = lua_tointeger(Lg, -1);
+ lua_remove(Lg, -1);
+ lua_getfield(Lg, -1, "y");
+ int y = lua_tointeger(Lg, -1);
+ lua_remove(Lg, -1);
+ lua_getfield(Lg, -1, "z");
+ int z = lua_tointeger(Lg, -1);
+ lua_remove(Lg, -1);
+ lua_remove(Lg, -1); // [player metatable __index]
+ lua_pushstring(Lg, "get_look_dir");
+ lua_rawget(Lg, -2); // [player metatable __index get_look_dir]
+ lua_pushvalue(Lg, -4);  // [player metatable __index get_look_dir player] 
+ lua_call(Lg, 1, 1); // [player metatable __index postable]
+ lua_getfield(Lg, -1, "x");
+ double xv = lua_tonumber(Lg, -1);
+ lua_remove(Lg, -1);
+ lua_getfield(Lg, -1, "z");
+ double zv = lua_tonumber(Lg, -1);
+ lua_remove(Lg, -1);
+ lua_remove(Lg, -1); // [player metatable __index]
+ lua_remove(Lg, -1); // [player metatable]
+ lua_remove(Lg, -1); // [player]
+ lua_remove(Lg, -1);
+ int facing = 0;
+ if (fabs(xv) > fabs(zv))
+ {
+  if (xv > 0)
+  {
+   facing = 2;
+   x += 2;
+  }
+  else
+   x -= 2;
+ }
+ else
+ {
+  if (zv > 0)
+  {
+   facing = 0;
+   z += 2;
+  }
+  else
+  {
+  facing = 3;
+   z -= 2;
+  }
+ }
+ y += 1;
+ duk_push_this(ctx);
+ duk_push_number(ctx, x);
+ duk_put_prop_string(ctx, -2, "x");
+ duk_push_number(ctx, y);
+ duk_put_prop_string(ctx, -2, "y");
+ duk_push_number(ctx, z);
+ duk_put_prop_string(ctx, -2, "z");
+ duk_push_number(ctx, facing);
+ duk_put_prop_string(ctx, -2, "facing");
+
+ return 0;  /* use default instance */
+}
+
+void drone_init(duk_context *ctx)
+{
+ duk_push_c_function(ctx, drone_constructor, 0);
+ duk_push_object(ctx);
+ duk_push_c_function(ctx, drone_box, 4);
+ duk_put_prop_string(ctx, -2, "box");
+ duk_put_prop_string(ctx, -2, "prototype");
+ duk_put_global_string(ctx, "Drone");
+}

scriptmine.c

@@ -1,12 +1,32 @@
-#include <lua.h>
-#include <lauxlib.h>
-#include <lualib.h>
-#include "duktape.h"
+#include "scriptmine.h"
 
 duk_context *ctx = NULL;
 lua_State *Lg = NULL;
 const char *name = NULL;
 
+const char *air = "air";
+const char *cobblestone = "default:cobble";
+const char *dirt = "default:dirt";
+const char *grass = "default:dirt_with_grass";
+const char *oakwood_plank = "default:wood";
+const char *stone = "default:stone";
+
+const char *blockID_to_node_name(int blockID)
+{
+ if (blockID == 1)
+  return stone;
+ else if (blockID == 2)
+  return grass;
+ else if (blockID == 3)
+  return dirt;
+ else if (blockID == 4)
+  return cobblestone;
+ else if (blockID == 5)
+  return oakwood_plank;
+ else
+  return air;
+}
+
 duk_ret_t echo(duk_context *ctx)
 {
  const char *text = duk_to_lstring(ctx, 0 /*index*/, NULL);
@@ -22,20 +42,22 @@ duk_ret_t echo(duk_context *ctx)
 
 static int javascript(lua_State *L)
 {
-	const char *cmd = lua_tostring(L, -1);
-	name = lua_tostring(L, -2);
+ const char *cmd = lua_tostring(L, -1);
+ name = lua_tostring(L, -2);
  Lg = L;
- duk_eval_string(ctx, cmd);
-	return 1;
+ duk_peval_string(ctx, cmd);
+ return 1;
 }
 
 int luaopen_scriptmine(lua_State *L)
 {
  ctx = duk_create_heap_default();
+ drone_init(ctx);
  duk_push_global_object(ctx);
  duk_push_c_function(ctx, echo, 1 /*nargs*/);
  duk_put_prop_string(ctx, -2, "echo");
- if (!ctx) {
+ if (!ctx)
+ {
   printf("Failed to create a Duktape heap.\n");
   exit(1);
  }

scriptmine.h

@@ -0,0 +1,10 @@
+#include <lua.h>
+#include <lauxlib.h>
+#include <lualib.h>
+#include "duktape.h"
+
+extern lua_State *Lg;
+extern const char *name;
+
+extern const char *blockID_to_node_name(int blockID);
+extern void drone_init(duk_context *ctx);