content: /*
   * Copyright (C) 2019 Adaptech s.r.o., Robert Pösel
   * Copyright (C) 2010 Google Inc.
   *
   * Licensed under the Apache License, Version 2.0 (the "License"); you may not
   * use this file except in compliance with the License. You may obtain a copy of
   * the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   * License for the specific language governing permissions and limitations under
   * the License.
   */
  
  package com.googlecode.leptonica.android;
  
  /**
   * Image scaling methods.
   *
   * @author alanv@google.com (Alan Viverette)
   */
  public class Scale {
  	static {
  		System.loadLibrary("jpeg");
  		System.loadLibrary("pngx");
  		System.loadLibrary("leptonica");
  	}
  
  	public enum ScaleType {
  		/* Scale in X and Y independently, so that src matches dst exactly. */
  		FILL,
  
  		/*
  		 * Compute a scale that will maintain the original src aspect ratio, but
  		 * will also ensure that src fits entirely inside dst. May shrink or
  		 * expand src to fit dst.
  		 */
  		FIT,
  
  		/*
  		 * Compute a scale that will maintain the original src aspect ratio, but
  		 * will also ensure that src fits entirely inside dst. May shrink src to
  		 * fit dst, but will not expand it.
  		 */
  		FIT_SHRINK,
  	}
  
  	/**
  	 * Scales the Pix to a specified width and height using a specified scaling
  	 * type (fill, stretch, etc.). Returns a scaled image or a clone of the Pix
  	 * if no scaling is required.
  	 *
  	 * @param pixs   Source pix image
  	 * @param width  The desired width to scale to
  	 * @param height The desired height to scale to
  	 * @param type   The desired scaling type
  	 * @return a scaled image or a clone of the Pix if no scaling is required
  	 */
  	public static Pix scaleToSize(Pix pixs, int width, int height, ScaleType type) {
  		if (pixs == null)
  			throw new IllegalArgumentException("Source pix must be non-null");
  
  		int pixWidth = pixs.getWidth();
  		int pixHeight = pixs.getHeight();
  
  		float scaleX = width / (float) pixWidth;
  		float scaleY = height / (float) pixHeight;
  
  		switch (type) {
  			case FILL:
  				// Retains default scaleX and scaleY values
  				break;
  			case FIT:
  				scaleX = Math.min(scaleX, scaleY);
  				//noinspection SuspiciousNameCombination
  				scaleY = scaleX;
  				break;
  			case FIT_SHRINK:
  				scaleX = Math.min(1.0f, Math.min(scaleX, scaleY));
  				//noinspection SuspiciousNameCombination
  				scaleY = scaleX;
  				break;
  		}
  
  		return scale(pixs, scaleX, scaleY);
  	}
  
  	/**
  	 * Scales the Pix to specified scale. If no scaling is required, returns a
  	 * clone of the source Pix.
  	 *
  	 * @param pixs  the source Pix
  	 * @param scale dimension scaling factor
  	 * @return a Pix scaled according to the supplied factors
  	 */
  	public static Pix scale(Pix pixs, float scale) {
  		return scale(pixs, scale, scale);
  	}
  
  	/**
  	 * Scales the Pix to the specified scale without sharpening.
  	 *
  	 * @param pixs  the source Pix (1, 2, 4, 8, 16 and 32 bpp)
  	 * @param scale scaling factor for both X and Y
  	 * @return a Pix scaled while maintaining its aspect ratio
  	 */
  	public static Pix scaleWithoutSharpening(Pix pixs, float scale) {
  		if (pixs == null)
  			throw new IllegalArgumentException("Source pix must be non-null");
  		if (scale <= 0.0f)
  			throw new IllegalArgumentException("Scaling factor must be positive");
  
  		return new Pix(nativeScaleGeneral(pixs.getNativePix(), scale, scale,
  				0f, 0));
  	}
  
  	/**
  	 * Scales the Pix to specified x and y scale. If no scaling is required,
  	 * returns a clone of the source Pix.
  	 *
  	 * @param pixs   the source Pix
  	 * @param scaleX x-dimension (width) scaling factor
  	 * @param scaleY y-dimension (height) scaling factor
  	 * @return a Pix scaled according to the supplied factors
  	 */
  	public static Pix scale(Pix pixs, float scaleX, float scaleY) {
  		if (pixs == null)
  			throw new IllegalArgumentException("Source pix must be non-null");
  		if (scaleX <= 0.0f)
  			throw new IllegalArgumentException("X scaling factor must be positive");
  		if (scaleY <= 0.0f)
  			throw new IllegalArgumentException("Y scaling factor must be positive");
  
  		long nativePix = nativeScale(pixs.getNativePix(), scaleX, scaleY);
  
  		if (nativePix == 0)
  			throw new RuntimeException("Failed to natively scale pix");
  
  		return new Pix(nativePix);
  	}
  
  	// ***************
  	// * NATIVE CODE *
  	// ***************
  
  	private static native long nativeScale(long nativePix, float scaleX, float scaleY);
  
  	private static native long nativeScaleGeneral(long nativePix, float scaleX, float scaleY, float sharpfract, int sharpwidth);
  
  }
  