Tool to parse XML texture atlas and generated Nit code to access subtextures

Redefined classes

redef class Sys

gamnit :: texture_atlas_parser $ Sys

The main class of the program.

All class definitions

redef class Sys

gamnit :: texture_atlas_parser $ Sys

The main class of the program.
package_diagram gamnit::texture_atlas_parser texture_atlas_parser dom dom gamnit::texture_atlas_parser->dom gen_nit gen_nit gamnit::texture_atlas_parser->gen_nit opts opts gamnit::texture_atlas_parser->opts parser_base parser_base dom->parser_base template template gen_nit->template core core opts->core ...parser_base ... ...parser_base->parser_base ...template ... ...template->template ...core ... ...core->core a_star-m a_star-m a_star-m->gamnit::texture_atlas_parser


module abstract_collection

core :: abstract_collection

Abstract collection classes and services.
module abstract_text

core :: abstract_text

Abstract class for manipulation of sequences of characters
module array

core :: array

This module introduces the standard array structure.
module bitset

core :: bitset

Services to handle BitSet
module bytes

core :: bytes

Services for byte streams and arrays
module caching

serialization :: caching

Services for caching serialization engines
module circular_array

core :: circular_array

Efficient data structure to access both end of the sequence.
module codec_base

core :: codec_base

Base for codecs to use with streams
module codecs

core :: codecs

Group module for all codec-related manipulations
module collection

core :: collection

This module define several collection classes.
module core

core :: core

Standard classes and methods used by default by Nit programs and libraries.
module engine_tools

serialization :: engine_tools

Advanced services for serialization engines
module environ

core :: environ

Access to the environment variables of the process
module error

core :: error

Standard error-management infrastructure.
module exec

core :: exec

Invocation and management of operating system sub-processes.
module file

core :: file

File manipulations (create, read, write, etc.)
module fixed_ints

core :: fixed_ints

Basic integers of fixed-precision
module fixed_ints_text

core :: fixed_ints_text

Text services to complement fixed_ints
module flat

core :: flat

All the array-based text representations
module gc

core :: gc

Access to the Nit internal garbage collection mechanism
module hash_collection

core :: hash_collection

Introduce HashMap and HashSet.
module inspect

serialization :: inspect

Refine Serializable::inspect to show more useful information
module iso8859_1

core :: iso8859_1

Codec for ISO8859-1 I/O
module kernel

core :: kernel

Most basic classes and methods.
module list

core :: list

This module handle double linked lists
module math

core :: math

Mathematical operations
module meta

meta :: meta

Simple user-defined meta-level to manipulate types of instances as object.
module native

core :: native

Native structures for text and bytes
module numeric

core :: numeric

Advanced services for Numeric types
module parser

dom :: parser

XML DOM-parsing facilities
module parser_base

parser_base :: parser_base

Simple base for hand-made parsers of all kinds
module protocol

core :: protocol

module queue

core :: queue

Queuing data structures and wrappers
module range

core :: range

Module for range of discrete objects.
module re

core :: re

Regular expression support for all services based on Pattern
module ropes

core :: ropes

Tree-based representation of a String.
module serialization

serialization :: serialization

General serialization services
module serialization_core

serialization :: serialization_core

Abstract services to serialize Nit objects to different formats
module sorter

core :: sorter

This module contains classes used to compare things and sorts arrays.
module stream

core :: stream

Input and output streams of characters
module template

template :: template

Basic template system
module text

core :: text

All the classes and methods related to the manipulation of text entities
module time

core :: time

Management of time and dates
module union_find

core :: union_find

union–find algorithm using an efficient disjoint-set data structure
module utf8

core :: utf8

Codec for UTF-8 I/O
module xml_entities

dom :: xml_entities

Basic blocks for DOM-XML representation


module dom

dom :: dom

Easy XML DOM parser
module gen_nit

gen_nit :: gen_nit

Support to generate and otherwise manipulate Nit code
module opts

opts :: opts

Management of options on the command line


module a_star-m


# Tool to parse XML texture atlas and generated Nit code to access subtextures
module texture_atlas_parser

import dom
import gen_nit
import opts

# Command line options
var opts = new OptionContext
var opt_name = new OptionString("Name of the module to generate", "--name", "-n")
var opt_dir = new OptionString("Folder where to write the generated module", "--dir")
opts.add_option(opt_name, opt_dir)
var rest =

if opts.errors.not_empty then
	print_error opts.errors
	exit 1

if rest.is_empty then
	print_error "Error: Expected the path to the XML file as argument"
	exit 2

# Prepare to read XML file and gather the attributes
var xml_file = rest.first
var attributes = new Array[String]

# Insert the first attribute, to load the root texture
var png_file = "images" / xml_file.basename("xml") + "png"
attributes.add """
	var root_texture = new TextureAsset("{{{png_file}}}")"""

# Read XML file
var content = xml_file.to_path.read_all
var xml = content.to_xml
if xml isa XMLError then
	print_error "RSS Parse Error: {xml.message}:{xml.location or else "null"}"
	exit 3

var items = xml["TextureAtlas"].first.children
for item in items do if item isa XMLOnelinerTag then
	var x = null
	var y = null
	var width = null
	var height = null
	var name = null
	for attr in item.attributes do if attr isa XMLStringAttr then
		if == "x" then
			x = attr.value.to_i
		else if == "y" then
			y = attr.value.to_i
		else if == "width" then
			width = attr.value.to_i
		else if == "height" then
			height = attr.value.to_i
		else if == "name" then
			name = attr.value

	if x != null and y != null and width != null and height != null and name != null then
		name = name.strip_extension(".png").to_snake_case

			var coords = "{x}, {y}, {width}, {height}"
			attributes.add """
	var {{{name}}}: Texture = root_texture.subtexture({{{coords}}})"""
		print_error "Error on {item}"

var module_name = opt_name.value
if module_name == null then module_name = "spritesheet"
var class_name = module_name.capitalized.to_camel_case

# Generate Nit code
var nit_module = new NitModule(module_name)
nit_module.header = """
# This file is generated by texture_atlas_parser

nit_module.content.add """
import gamnit::display
import gamnit::textures

class {{{class_name}}}

for a in attributes do nit_module.content.add a

nit_module.content.add """

var dir = opt_dir.value
if dir != null then
	var out_path = dir / module_name + ".nit"
	nit_module.write_to_file out_path
	printn nit_module.write_to_string