IconWriter

A simple solution for encoding common icon file formats, such as .ico and .icns. This crate is mostly a wrapper for other libraries, unifying existing APIs into a single, cohesive interface.

Overview

An icon stores a collection of small images of different sizes. Individual images within the icon are bound to a source image, which is rescaled to fit a particular size using a resampling filter.

Resampling filters are represented by functions that take a source image and a size and return a rescaled raw RGBA buffer. This allows the user of this crate to provide their custom resampling filter. Common resampling filters are provided by the resample module.

Examples

General Usage

```rust use iconwriter::*;

fn main() -> iconwriter::Result<()> { let icon = Ico::new(); match SourceImage::frompath("image.svg") { Some(img) => icon.addentry(resample::linear, &img, 32), None => Ok(()) } } ```

Writing to a File

```rust use iconwriter::*; use std::{io, fs::File};

fn main() -> io::Result<()> { let icon = PngSequence::new();

/* Process the icon */

let file = File::create("ou.icns")?;
icon.write(file)

} ```

Limitations

There are two main limitations in this crate: both ICNS and SVG are not fully supported. Due to the use of external dependencies, this crate is not able to fully support the formal specifications of those two file formats.

Supported Image Formats

| Format | Supported? | | ------ | -------------------------------------------------- | | PNG | All supported color types | | JPEG | Baseline and progressive | | GIF | Yes | | BMP | Yes | | ICO | Yes | | TIFF | Baseline(no fax support), LZW, PackBits | | WEBP | Lossy(Luma channel only) | | PNM | PBM, PGM, PPM, standard PAM | | SVG | Limited(flat filled shapes only) |

ICNS Support

However, the coverage provided by these external dependencies should be more than enought for most use cases.

Icon Writer uses the icns crate for generating .icns files. The supported icon types are specified by the creators of such crate as follows:

| OSType | Description | Supported? | |--------|-----------------------------------------|------------| | ICON | 32×32 1-bit icon | No | | ICN# | 32×32 1-bit icon with 1-bit mask | No | | icm# | 16×12 1-bit icon with 1-bit mask | No | | icm4 | 16×12 4-bit icon | No | | icm8 | 16×12 8-bit icon | No | | ics# | 16×16 1-bit mask | No | | ics4 | 16×16 4-bit icon | No | | ics8 | 16x16 8-bit icon | No | | is32 | 16×16 24-bit icon | Yes | | s8mk | 16x16 8-bit mask | Yes | | icl4 | 32×32 4-bit icon | No | | icl8 | 32×32 8-bit icon | No | | il32 | 32x32 24-bit icon | Yes | | l8mk | 32×32 8-bit mask | Yes | | ich# | 48×48 1-bit mask | No | | ich4 | 48×48 4-bit icon | No | | ich8 | 48×48 8-bit icon | No | | ih32 | 48×48 24-bit icon | Yes | | h8mk | 48×48 8-bit mask | Yes | | it32 | 128×128 24-bit icon | Yes | | t8mk | 128×128 8-bit mask | Yes | | icp4 | 16x16 32-bit PNG/JP2 icon | PNG only | | icp5 | 32x32 32-bit PNG/JP2 icon | PNG only | | icp6 | 64x64 32-bit PNG/JP2 icon | PNG only | | ic07 | 128x128 32-bit PNG/JP2 icon | PNG only | | ic08 | 256×256 32-bit PNG/JP2 icon | PNG only | | ic09 | 512×512 32-bit PNG/JP2 icon | PNG only | | ic10 | 512x512@2x "retina" 32-bit PNG/JP2 icon | PNG only | | ic11 | 16x16@2x "retina" 32-bit PNG/JP2 icon | PNG only | | ic12 | 32x32@2x "retina" 32-bit PNG/JP2 icon | PNG only | | ic13 | 128x128@2x "retina" 32-bit PNG/JP2 icon | PNG only | | ic14 | 256x256@2x "retina" 32-bit PNG/JP2 icon | PNG only |

SVG Support

IconWriter uses the nsvg crate for rasterizing .svg files. According to the authors of the crate:

Like NanoSVG, the rasterizer only renders flat filled shapes. It is not particularly fast or accurate, but it is a simple way to bake vector graphics into textures.

The author of iconwriter is inclined to search for alternatives to nsvg if inquired to. Help would be appreciated.