$ cd LuaNativeObjects/project_template/
$ lua RUN_THIS_FIRST.lua

-- define the 'gd' module
c_module "gd" {
	-- when set to true all objects will be registered as a global for easy access.
	use_globals = true,
	
	-- enable FFI bindings support.
	luajit_ffi = true,
	
	-- load GD shared library.
	ffi_load"gd",
	
	-- include library's header file
	include "gd.h",

	object "gdImage" {
		-- Use `ffi_cdef` records to pass extra C type info to FFI.
		ffi_cdef[[
		typedef struct gdImageStruct gdImage;
	]],
		-- The first constructor can be called as: gd.gdImage(x,y) or gd.gdImage.new(x,y)
		-- The default name for a constructor is 'new'
	  constructor {
	    c_call "gdImage *" "gdImageCreate" { "int", "sx", "int", "sy" }
	  },
		-- Other constructors can be called by there name: gd.gdImage.newTrueColor(x,y)
	  constructor "newTrueColor" {
	    c_call "gdImage *" "gdImageCreateTrueColor" { "int", "sx", "int", "sy" }
	  },
		-- A named destructor allows freeing of the object before it gets GC'ed.
	  destructor "close" {
	    c_method_call "void" "gdImageDestroy" {}
	  },
	
	  method "color_allocate" {
			-- bindings for simple methods/functions can be generated with `c_method_call` or `c_call`
			-- records, which will generate both Lua API & FFI based bindings for the function.
	    c_method_call "int" "gdImageColorAllocate"
	      { "int", "r", "int", "g", "int", "b" }
	  },
	
	  method "line" {
	    c_method_call "void" "gdImageLine"
	      { "int", "x1", "int", "y1", "int", "x2", "int", "y2", "int", "colour" }
	  },
	
		-- The next method need extra FFI types & function information.
		ffi_cdef[[
		/* dummy typedef for "FILE" */
		typedef struct FILE FILE;
	
		FILE *fopen(const char *path, const char *mode);
		int fclose(FILE *fp);
	
		void gdImagePng(gdImage *im, FILE *out);
	]],
		-- This method is more complex and can't be generated with a simple `c_method_call` record.
	  method "toPNG" {
			-- Use `var_in`/`var_out` records to define parameters & return values.
	    var_in { "const char *", "name" },
			-- Use `c_source` records to provide the C code for this method.
	    c_source [[
	  FILE *pngout = fopen( ${name}, "wb");
	  gdImagePng(${this}, pngout);
	  fclose(pngout);
	]],
			-- if you want this method to have FFI-based bindings you will need to use a `ffi_source` record
	    ffi_source [[
	  local pngout = ffi.C.fopen(${name}, "wb")
	  C.gdImagePng(${this}, pngout)
	  ffi.C.fclose(pngout)
	]]
	  },
	}
}

c_call "int>1" "func_name"
  { "ObjectType1", "&need_pointer_to_pointer_is_out_var_idx2>2", "ClassObject", "this<1" }