Package crunch on DUB

To use this package, run the following command in your project's root directory:

crunch

This is a command line tool that will pack a bunch of images into a single, larger image. It was designed for Celeste, but could be very helpful for other games.

It is designed using libraries with permissible licenses, so you are able to use it freely in your commercial and non-commercial projects. Please see each source file for its respective copyright and license.

Features

Export XML, JSON, or binary data
Trim excess transparency
Rotate images to fit
Control atlas size and padding
Premultiply pixel values
Recursively scans folders
Remove duplicate images
Caching to prevent redundant builds
Multi-image atlas when the sprites don't fit

What does it do?

Given a folder with several images, like so:

images/
    player.png
    tree.png
    enemy.png

It will output something like this:

bin/
    images.png
    images.xml
    images.hash

Where images.png is the packed image, images.xml is an xml file describing where each sub-image is located, and images.hash is used for file caching (if none of the input files have changed since the last pack, the program will terminate).

There is also an option to use a binary format instead of xml.

Usage

crunch [OUTPUT] [INPUT1,INPUT2,INPUT3...] [OPTIONS...]

For example...

crunch bin/atlases/atlas assets/characters,assets/tiles -p -t -v -u -r -j

This will output the following files:

bin/atlases/atlas.png
bin/atlases/atlas.json
bin/atlases/atlas.hash

Options

option	alias	description
-d	--default	use default settings (-x -p -t -u)
-x	--xml	saves the atlas data as a .xml file
-b	--binary	saves the atlas data as a .bin file
-c	--compact	saves the atlas data as a .bin file (with extra metadata and optimized for fast reading)
-j	--json	saves the atlas data as a .json file
-p	--premultiply	premultiplies the pixels of the bitmaps by their alpha channel
-t	--trim	trims excess transparency off the bitmaps
-v	--verbose	print to the debug console as the packer works
-f	--force	ignore caching, forcing the packer to repack
-u	--unique	remove duplicate bitmaps from the atlas
-r	--rotate	enabled rotating bitmaps 90 degrees clockwise when packing
-s#	--size#	max atlas size (# can be 4096, 2048, 1024, 512, 256, 128, or 64)
-p#	--pad#	padding between images (# can be from 0 to 16)
-ba#	--balign#	align binary output (# can be 4096, 2048, 1024, 512, 256, 128 or 64)

Binary Format

The --compact switch adds this additional preamble containing magic number and version

(not in --binary output)
63 72 6E C7 49 31 5B  magic number ("crn\xC7I1[")
00                    format version number. Unsupported versions must be considered unknown.
                      Only a format change should change this version number.

[int16] alignment
[int16] size
[byte] padding
[byte] crunch_flags

crunch_flags:

0x01 premultiplied
0x02 trim enabled
0x04 rotation enabled
0x08 unique

the 2 most significant bits can be used for any user data and will not be written by crunch.

Additionally --compact sorts (ascending, ordinal) images by img_name. Binary will also do so if generated with a version of the tool supporting --compact, however specifying compact should be preferred.

[int16] num_textures (below block is repeated this many times)
        [string] name (sorted)
        [int16] num_images (below block is repeated this many times)
        // with --compact this is padded to the next 512 bytes (if not on one already)
            [string] img_name (not in --compact)
            [int16] img_x
            [int16] img_y
            [int16] img_width
            [int16] img_height
            [int16] img_frame_x         (if --trim enabled)
            [int16] img_frame_y         (if --trim enabled)
            [int16] img_frame_width     (if --trim enabled)
            [int16] img_frame_height    (if --trim enabled)
            [byte] img_rotated          (if --rotate enabled)
            [string] img_name (only in --compact, moved to end)
            // with --compact each image is padded to specified bytes (and must not exceed that in size)

Type notes:

strings are null-terminated in --binary
strings are length prefixed (2 byte length) without null-terminator in --compact
numbers are little-endian encoded

License

Unless otherwise specified in a source file, everything in this project falls under the following license:

MIT License

Copyright (c) 2017 Chevy Ray Johnston

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

The D reading library (being files dub.sdl and reader/d/crunch.d) is separately licensed as public domain.

0.1.0	2019-Mar-16
~master	2019-Mar-16