create_texturelist.py

# Based on http://code.activestate.com/recipes/442299/
import glob
import os

from lxml import etree
from lxml.builder import E
from PIL import Image


class PackNode(object):
    """
    Creates an area which can recursively pack other areas of smaller sizes into itself.
    """

    def __init__(self, area):
        # if tuple contains two elements
        # assume they are width and height, and origin is (0,0)
        if len(area) == 2:
            area = (0, 0, area[0], area[1])

        self.area = area

    def __repr__(self):
        return "<%s %s>" % (self.__class__.__name__, str(self.area))

    def get_width(self):
        return self.area[2] - self.area[0]

    width = property(fget=get_width)

    def get_height(self):
        return self.area[3] - self.area[1]

    height = property(fget=get_height)

    def insert(self, area):
        if hasattr(self, "child"):
            a = self.child[0].insert(area)
            if a is None:
                return self.child[1].insert(area)
            return a

        area = PackNode(area)
        if area.width <= self.width and area.height <= self.height:
            self.child = [None, None]
            self.child[0] = PackNode(
                (
                    self.area[0] + area.width,
                    self.area[1],
                    self.area[2],
                    self.area[1] + area.height,
                )
            )
            self.child[1] = PackNode(
                (self.area[0], self.area[1] + area.height, self.area[2], self.area[3])
            )
            return PackNode(
                (
                    self.area[0],
                    self.area[1],
                    self.area[0] + area.width,
                    self.area[1] + area.height,
                )
            )


def create_texturelist(input, output):
    size = 1024, 1024

    names = glob.glob(os.path.join(input, "*.png"))

    images = [
        (i.size[0] * i.size[1], os.path.basename(name), i)
        for name, i in ((x, Image.open(x)) for x in names)
    ]

    tree = PackNode(size)

    package_texture = []
    current_texture = []

    while len(images) > 0:
        images_not_used = []

        # insert each image into the PackNode area
        for area, name, img in images:
            uv = tree.insert(img.size)

            if uv is None:
                images_not_used.append((area, name, img))
            else:
                current_texture.append((uv, name))

        images = images_not_used
        tree = PackNode(size)

        package_texture.append(current_texture)
        current_texture = []

    textures = [
        E.texture(
            E.size(
                "{} {}".format(size[0], size[1]),
                __type="2u16",
            ),
            *[
                E.image(
                    E.uvrect(
                        "{} {} {} {}".format(
                            (texture[0].area[0] + 1) * 2,
                            (texture[0].area[2] - 1) * 2,
                            (texture[0].area[1] + 1) * 2,
                            (texture[0].area[3] - 1) * 2,
                        ),
                        __type="4u16",
                    ),
                    E.imgrect(
                        "{} {} {} {}".format(
                            texture[0].area[0] * 2,
                            texture[0].area[2] * 2,
                            texture[0].area[1] * 2,
                            texture[0].area[3] * 2,
                        ),
                        __type="4u16",
                    ),
                    name=os.path.splitext(texture[1])[0],
                )
                for texture in package_texture[i]
            ],
            format="argb8888rev",
            mag_filter="nearest",
            min_filter="nearest",
            name="tex{0:03d}".format(i),
            wrap_s="clamp",
            wrap_t="clamp"
        )
        for i in range(0, len(package_texture))
    ]

    texturelist = E.texturelist(*textures, compress="avslz")

    open(output, "wb").write(etree.tostring(texturelist, pretty_print=True))


if __name__ == "__main__":
    create_texturelist("", "texturelist.xml")