Scripting WIP (#70)

* Scripting introduced

* AppImage workflow fixes

* AppImage workflow simplified

* README.md update

* README.md update

* small fix

src/logic/scripting/api_lua.cpp

@@ -0,0 +1,65 @@
+#include "api_lua.h"
+#include "scripting.h"
+
+#include "../../world/Level.h"
+#include "../../content/Content.h"
+#include "../../voxels/Block.h"
+#include "../../voxels/Chunks.h"
+#include "../../voxels/voxel.h"
+
+int l_block_name(lua_State* L) {
+    int id = lua_tointeger(L, 1);
+    lua_pushstring(L, scripting::content->indices->getBlockDef(id)->name.c_str());
+    return 1;
+}
+
+int l_is_solid_at(lua_State* L) {
+    int x = lua_tointeger(L, 1);
+    int y = lua_tointeger(L, 2);
+    int z = lua_tointeger(L, 3);
+
+    lua_pushboolean(L, scripting::level->chunks->isSolid(x, y, z));
+    return 1;
+}
+
+int l_blocks_count(lua_State* L) {
+    lua_pushinteger(L, scripting::content->indices->countBlockDefs());
+    return 1;
+}
+
+int l_block_index(lua_State* L) {
+    auto name = lua_tostring(L, 1);
+    lua_pushinteger(L, scripting::content->requireBlock(name)->rt.id);
+    return 1;
+}
+
+int l_set_block(lua_State* L) {
+    int x = lua_tointeger(L, 1);
+    int y = lua_tointeger(L, 2);
+    int z = lua_tointeger(L, 3);
+    int id = lua_tointeger(L, 4);    
+    scripting::level->chunks->set(x, y, z, id, 0);
+    return 0;
+}
+
+int l_get_block(lua_State* L) {
+    int x = lua_tointeger(L, 1);
+    int y = lua_tointeger(L, 2);
+    int z = lua_tointeger(L, 3);
+    voxel* vox = scripting::level->chunks->get(x, y, z);
+    int id = vox == nullptr ? -1 : vox->id;
+    lua_pushinteger(L, id);
+    return 1;
+}
+
+#define lua_addfunc(L, FUNC, NAME) (lua_pushcfunction(L, FUNC),\
+                                    lua_setglobal(L, NAME))
+
+void apilua::create_funcs(lua_State* L) {
+    lua_addfunc(L, l_block_index, "block_index");
+    lua_addfunc(L, l_block_name, "block_name");
+    lua_addfunc(L, l_blocks_count, "blocks_count");
+    lua_addfunc(L, l_is_solid_at, "is_solid_at");
+    lua_addfunc(L, l_set_block, "set_block");
+    lua_addfunc(L, l_get_block, "get_block");
+}