Generate automatically resized splashscreens and icons for mobile platforms, e.g. for Cordova based projects.

• Installation
• Usage
  • From the command-line
  • In your own scripts
  • Special cases
    • NinePatch images
    • Transparency
    • Small templates
• Specifications
• Add to your Cordova project
• Thanks

Installation

Inside of your project directory:

 % npm install resources-generator

The script depends on imageMagick, it needs to be installed: macOS:

 % brew install imagemagick

Linux / apt:

 % sudo apt-get install imagemagick

Usage

Your splash template should be a 2732x2732px image, and the main content should fit a center square of 1200x1200px.

Your icon template should be a 1024x1024px image. For Android you have to take care of the rounded corners yourself, everything you don't want to see must be transparent - so your best choice is to use a png-template. Please also note chapter transparency below.

When using the default specifications or the command-line version you need to prepare your templates as following:

• Splashscreen template for Android and iOS as ./model/splash.png
• Icon template for Android as ./model/android/icon.png
• Icon template for iOS as ./model/ios/icon.png

For any individual requirements please see chapter in your own scripts.

From the command-line

The package includes a binary that can be called as resources-generator from within your project (or from everywhere when the package was installed globally). When called without any parameters a hint on how to use it is given:

 % resources-generator
Usage: resources-generator --platform=(android|ios) --type=(splash|icon) [--source="./image.png"] [--targetDir="./put/it/here/"]
Please provide at least platform and type.

The binary uses the default targets for Android respectively iOS as described in specifications, you can change the source-image (via --source="./myimage.png") and the directory where the results shall be saved (via --targetDir).

Hint: To be able to directly use locally installed node binaries make sure to add the following to your .bashrc or .zshrc:

# use locally installed node bins
PATH="./node_modules/.bin:$PATH"

In your own scripts

If you want to define your own specifications the best choice is to build your own script.
A good starting point are the predefined specifications from dist/specs.

Example:

import { 
  generateResource,
  ResourceDefinition 
} from "resources-generator";
import {
  androidSplashDefaults,
  androidIconDefaults,
  androidNotificationIconDefaults,
  iosSplashDefaults,
  iosIconDefaults
} from "resources-generator/dist/specs";

//change the template for Android splashcreens
androidSplashDefaults.sourceFile = "./model/android/splash.png";

//add additional 256px Android icon
androidIconDefaults.targets.push({
  fileName: "icon-256.png",
  width: 256
});

// create icons for our PWA, based on the android icon template
let pwa:ResourceDefinition = {
  description: "PWA icons",
  sourceFile: "./model/android/icon.png",
  targetDir: "./src/assets/icon/",
  keepAlpha: true,
  targets: [
    { fileName: "icon-192.png", width: 192 },
    { fileName: "icon-512.png", width: 512 },
    { fileName: "favicon.ico", width: 64 }
  ]
};

//collect all resources we want to generate
let resources = [
  androidSplashDefaults,
  androidIconDefaults,
  androidNotificationIconDefaults,
  iosSplashDefaults,
  iosIconDefaults,
  pwa
];

//create one after the other
resources.reduce((func, resource) => {
  return func
    .then(_ => generateResource(resource))
    .catch(e => {
      return;
    });
}, Promise.resolve());

You may save this script inside of your projects as scripts/generate-resources.ts and add to your package.json:

{
...
  "scripts": {
    ...
    "resources:generate": "cross-env TS_NODE_COMPILER_OPTIONS='{ \"module\": \"commonjs\" }' ts-node scripts/generate-resources.ts"
  },
  ...
}

Now you are able to call npm run resources:generate to regenerate your resources.

For a plain node example please see bin/resources-generator.

Special cases

NinePatch images

Android supports NinePatch drawables for its splashscreens - this project automatically generates them when your targets fileName has the extension *.9.png , e.g. screen-mdpi-portrait.9.png.

The Android splashscreen defaults in dist/specs are configured to generate NinePatch files.

Hint: To make nine-patch splashscreen work in Cordova projects you need to set

<preference name="SplashMaintainAspectRatio" value="false" />

in your config.xml!

Transparency

When nothing else is declared Alpha channel (transparency) is removed from the resulting resource images.
If you want to keep transparency you need to set this in your ResourceDefinition by declaring keepAlpha as true. The Android icon defaults in dist/specs are configured to preserve transparency.

As NinePatch images are based on transparent areas alpha channel is preserved here in every case.

Small templates

As noted your templates should be 2732x2732px for splashscreens. This requirement is based on the required image size for iPad Pro splashscreens, see Apple Human Interface Guidelines.

If you request the script to generate a resource image that is bigger then the provided template the template is never scaled up! Instead we stretch the most outer regions until the desired size is met (this kind-of imitates what is done with NinePatch images).

Specifications

To generate resources your input needs to follow some specifications, they are described by interfaces that can be imported from the package.

export interface TargetSpecification {
  fileName: string;
  width: number;
  height?: number; //height is optional, if only width is given we assume a square target
}

export interface ResourceDefinition {
  description: string;
  sourceFile: string;
  keepAlpha?: boolean; //sometimes we need to keep the Alpha-Channel (e.g. Android icons)
  targetDir: string; //directory where to store the generated resources
  targets: Array<TargetSpecification>;
}

To make the script usable straight away we defined some defaults for splashscreens and icons for Android and iOS.

They can be imported from dist/specs.

We predefined the following:

export let androidSplashDefaults: ResourceDefinition = {
  description: "Splashscreens for Android",
  sourceFile: "./model/splash.png",
  targetDir: "./res/screens/android/",
  targets: [
    { fileName: "screen-ldpi-portrait.9.png", width: 320, height: 426 },
    { fileName: "screen-ldpi-landscape.9.png", width: 426, height: 320 },
    { fileName: "screen-hdpi-portrait.9.png", width: 480, height: 640 }, // 320x480
    { fileName: "screen-hdpi-landscape.9.png", width: 640, height: 480 }, // 480x320
    { fileName: "screen-mdpi-portrait.9.png", width: 320, height: 470 }, // 480x800
    { fileName: "screen-mdpi-landscape.9.png", width: 470, height: 320 }, // 800x480
    { fileName: "screen-xhdpi-portrait.9.png", width: 720, height: 960 }, // 720x1280
    { fileName: "screen-xhdpi-landscape.9.png", width: 960, height: 720 }, // 1280x720
    { fileName: "screen-xxhdpi-portrait.9.png", width: 960, height: 1600 }, // 960x1600
    { fileName: "screen-xxhdpi-landscape.9.png", width: 1600, height: 960 }, // 1600x960
    { fileName: "screen-xxxhdpi-portrait.9.png", width: 1280, height: 1920 }, // 1280x1920
    { fileName: "screen-xxxhdpi-landscape.9.png", width: 1920, height: 1280 } // 1920x1280
  ]
};

export let iosSplashDefaults: ResourceDefinition = {
  description: "Splashscreens for iOS (Storyboards)",
  sourceFile: "./model/splash.png",
  targetDir: "./res/screens/ios/",
  targets: [
    { fileName: "Default@2x~universal~anyany.png", width: 2732, height: 2732 },
    { fileName: "Default@2x~universal~comany.png", width: 1278, height: 2732 },
    { fileName: "Default@2x~universal~comcom.png", width: 1334, height: 750 },
    { fileName: "Default@3x~universal~anyany.png", width: 2208, height: 2208 },
    { fileName: "Default@3x~universal~anycom.png", width: 2208, height: 1242 },
    { fileName: "Default@3x~universal~comany.png", width: 1242, height: 2208 }
  ]
};

export let androidIconDefaults: ResourceDefinition = {
  description: "Icon files for Android",
  sourceFile: "./model/android/icon.png",
  keepAlpha: true,
  targetDir: "./res/icons/android/",
  targets: [
    //Play Store Icon
    { fileName: "icon-512.png", width: 512 },
    //Icons for densities ldpi to xxxhdpi
    { fileName: "icon-36-ldpi.png", width: 36 },
    { fileName: "icon-48-mdpi.png", width: 48 },
    { fileName: "icon-72-hdpi.png", width: 72 },
    { fileName: "icon-96-xhdpi.png", width: 96 },
    { fileName: "icon-144-xxhdpi.png", width: 144 },
    { fileName: "icon-192-xxxhdpi.png", width: 192 }
  ]
};

export let iosIconDefaults: ResourceDefinition = {
  description: "Icon files for iOS",
  sourceFile: "./model/ios/icon.png",
  targetDir: "./res/icons/ios/",
  targets: [
    //App Store Icon
    { fileName: "icon-1024.png", width: 1024 },
    //iOS 8.0+
    //iPhone 6 Plus
    { fileName: "[email protected]", width: 180 },
    //iOS 7.0+
    //iPhone / iPod Touch
    { fileName: "icon-60.png", width: 60 },
    { fileName: "[email protected]", width: 120 },
    //iPad
    { fileName: "icon-76.png", width: 76 },
    { fileName: "[email protected]", width: 152 },
    //Spotlight Icon
    { fileName: "icon-40.png", width: 40 },
    { fileName: "[email protected]", width: 80 },
    //iOS 6.1
    //iPhone / iPod Touch
    { fileName: "icon.png", width: 57 },
    { fileName: "[email protected]", width: 114 },
    //iPad
    { fileName: "icon-72.png", width: 72 },
    { fileName: "[email protected]", width: 144 },
    //iPad Pro
    { fileName: "icon-167.png", width: 167 },
    //iPhone Spotlight and Settings Icon
    { fileName: "icon-small.png", width: 29 },
    { fileName: "[email protected]", width: 58 },
    { fileName: "[email protected]", width: 87 },
    //iPad Spotlight and Settings Icon
    { fileName: "icon-50.png", width: 50 },
    { fileName: "[email protected]", width: 100 },
    //iPad Pro
    { fileName: "[email protected]", width: 167 },

    // we also need 20x20 for iPad Notification 20pt@1
    { fileName: "icon-20.png", width: 20 },

    //Apple-Watch
    { fileName: "[email protected]", width: 48 },
    { fileName: "[email protected]", width: 55 },
    { fileName: "[email protected]", width: 172 },
    { fileName: "[email protected]", width: 196 }
  ]
};

Add to your Cordova project

You can add the resources generated by the specifications described above to your Cordova project config.xml in the following way:

    <platform name="android">
        <allow-intent href="market:*" />
        <icon density="ldpi" src="res/icons/android/icon-36-ldpi.png" />
        <icon density="mdpi" src="res/icons/android/icon-48-mdpi.png" />
        <icon density="hdpi" src="res/icons/android/icon-72-hdpi.png" />
        <icon density="xhdpi" src="res/icons/android/icon-96-xhdpi.png" />
        <icon density="xxhdpi" src="res/icons/android/icon-144-xxhdpi.png" />
        <icon density="xxxhdpi" src="res/icons/android/icon-192-xxxhdpi.png" />
        <splash density="land-hdpi" src="res/screens/android/screen-hdpi-landscape.9.png" />
        <splash density="land-ldpi" src="res/screens/android/screen-ldpi-landscape.9.png" />
        <splash density="land-mdpi" src="res/screens/android/screen-mdpi-landscape.9.png" />
        <splash density="land-xhdpi" src="res/screens/android/screen-xhdpi-landscape.9.png" />
        <splash density="land-xxhdpi" src="res/screens/android/screen-xxhdpi-landscape.9.png" />
        <splash density="land-xxxhdpi" src="res/screens/android/screen-xxxhdpi-landscape.9.png" />
        <splash density="port-hdpi" src="res/screens/android/screen-hdpi-portrait.9.png" />
        <splash density="port-ldpi" src="res/screens/android/screen-ldpi-portrait.9.png" />
        <splash density="port-mdpi" src="res/screens/android/screen-mdpi-portrait.9.png" />
        <splash density="port-xhdpi" src="res/screens/android/screen-xhdpi-portrait.9.png" />
        <splash density="port-xxhdpi" src="res/screens/android/screen-xxhdpi-portrait.9.png" />
        <splash density="port-xxxhdpi" src="res/screens/android/screen-xxxhdpi-portrait.9.png" />
    </platform>
    <preference name="SplashMaintainAspectRatio" value="false" />

    <platform name="ios">
        <allow-intent href="itms:*" />
        <allow-intent href="itms-apps:*" />
        <icon src="res/icons/ios/[email protected]" width="180" height="180" />
        <icon src="res/icons/ios/icon-60.png" width="60" height="60" />
        <icon src="res/icons/ios/[email protected]" width="120" height="120" />
        <icon src="res/icons/ios/icon-76.png" width="76" height="76" />
        <icon src="res/icons/ios/[email protected]" width="152" height="152" />
        <icon src="res/icons/ios/icon-40.png" width="40" height="40" />
        <icon src="res/icons/ios/[email protected]" width="80" height="80" />
        <icon src="res/icons/ios/icon.png" width="57" height="57" />
        <icon src="res/icons/ios/[email protected]" width="114" height="114" />
        <icon src="res/icons/ios/icon-72.png" width="72" height="72"/>
        <icon src="res/icons/ios/[email protected]" width="144" height="144"/>
        <icon src="res/icons/ios/icon-167.png" width="167" height="167"/>
        <icon src="res/icons/ios/icon-small.png" width="29" height="29"/>
        <icon src="res/icons/ios/[email protected]" width="58" height="58"/>
        <icon src="res/icons/ios/[email protected]" width="87" height="87"/>
        <icon src="res/icons/ios/icon-50.png" width="50" height="50"/>
        <icon src="res/icons/ios/[email protected]" width="100" height="100" />
        <icon src="res/icons/ios/[email protected]" width="167" height="167"/>
        <icon src="res/icons/ios/icon-20.png" width="20" height="20"/>
        <icon src="res/icons/ios/[email protected]" width="48" height="48"/>
        <icon src="res/icons/ios/[email protected]" width="55" height="55"/>
        <icon src="res/icons/ios/[email protected]" width="172" height="172"/>
        <icon src="res/icons/ios/[email protected]" width="196" height="196"/>
        <icon src="res/icons/ios/icon-1024.png" width="1024" height="1024"/>
        <splash src="res/screens/ios/Default@2x~universal~anyany.png" />
        <splash src="res/screens/ios/Default@2x~universal~comany.png" />
        <splash src="res/screens/ios/Default@2x~universal~comcom.png" />
        <splash src="res/screens/ios/Default@3x~universal~anyany.png" />
        <splash src="res/screens/ios/Default@3x~universal~anycom.png" />
        <splash src="res/screens/ios/Default@3x~universal~comany.png" />
    </platform>

Thanks

This script is inspired by splashicon-generator and TiCons.

It makes use of gm and imageMagick.