VdToPng.kt

package com.android.ide.common.vectordrawable

import java.awt.image.BufferedImage
import java.io.File
import java.io.InputStream
import javax.imageio.ImageIO

/**
 * Converts a VectorDrawable to a BufferedImage.
 * Please note that this has to live inside the com.android.ide.common.vectordrawable package so that 
 * it can use the internal VdParser class. This is available in the com.android.tools:sdk-common package, which is
 * a dependency of apkanalyzer
 * @param inputStream input stream for reading the VectorDrawable
 */
fun vdToBufferedImage(inputStream: InputStream): BufferedImage {
    val errorLog = StringBuilder()
    val tree = VdParser.parse(inputStream, errorLog)
    // println(errorLog.toString())
    /*
     * TODO: The baseWidth and baseHeight are are used for the image width and height. This is the MDPI size.
     *  Consider allowing passing of density and scaling the image size to match.
     */
    val bufferedImage = BufferedImage(tree.baseWidth.toInt(),tree.baseHeight.toInt(),BufferedImage.TYPE_INT_ARGB)
    tree.drawIntoImage(bufferedImage)
    return bufferedImage
}

/**
 * Write a vector image to a png.
 * @param inputStream input stream for reading the VectorDrawable
 * @param path path to the file to write to
 */
fun vdToPng(inputStream: InputStream, path: String) {
    ImageIO.write(vdToBufferedImage(inputStream),"PNG", File(path))    
}