content: /*
   * Copyright (C) 2007 The Android Open Source Project
   *
   * 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 android.graphics;
  
  import android.annotation.ColorInt;
  import android.annotation.ColorLong;
  import android.annotation.NonNull;
  import android.annotation.Nullable;
  import android.annotation.UnsupportedAppUsage;
  
  
  public class LinearGradient extends Shader {
      @UnsupportedAppUsage
      private float mX0;
      @UnsupportedAppUsage
      private float mY0;
      @UnsupportedAppUsage
      private float mX1;
      @UnsupportedAppUsage
      private float mY1;
      @UnsupportedAppUsage
      private float[] mPositions;
      @UnsupportedAppUsage
      private TileMode mTileMode;
  
      // @ColorInts are replaced by @ColorLongs, but these remain due to @UnsupportedAppUsage.
      @UnsupportedAppUsage
      @ColorInt
      private int[] mColors;
      @UnsupportedAppUsage
      @ColorInt
      private int mColor0;
      @UnsupportedAppUsage
      @ColorInt
      private int mColor1;
  
      @ColorLong
      private final long[] mColorLongs;
  
  
      /**
       * Create a shader that draws a linear gradient along a line.
       *
       * @param x0           The x-coordinate for the start of the gradient line
       * @param y0           The y-coordinate for the start of the gradient line
       * @param x1           The x-coordinate for the end of the gradient line
       * @param y1           The y-coordinate for the end of the gradient line
       * @param colors       The sRGB colors to be distributed along the gradient line
       * @param positions    May be null. The relative positions [0..1] of
       *                     each corresponding color in the colors array. If this is null,
       *                     the the colors are distributed evenly along the gradient line.
       * @param tile         The Shader tiling mode
       */
      public LinearGradient(float x0, float y0, float x1, float y1, @NonNull @ColorInt int[] colors,
              @Nullable float[] positions, @NonNull TileMode tile) {
          this(x0, y0, x1, y1, convertColors(colors), positions, tile,
                  ColorSpace.get(ColorSpace.Named.SRGB));
      }
  
      /**
       * Create a shader that draws a linear gradient along a line.
       *
       * @param x0           The x-coordinate for the start of the gradient line
       * @param y0           The y-coordinate for the start of the gradient line
       * @param x1           The x-coordinate for the end of the gradient line
       * @param y1           The y-coordinate for the end of the gradient line
       * @param colors       The colors to be distributed along the gradient line
       * @param positions    May be null. The relative positions [0..1] of
       *                     each corresponding color in the colors array. If this is null,
       *                     the the colors are distributed evenly along the gradient line.
       * @param tile         The Shader tiling mode
       *
       * @throws IllegalArgumentException if there are less than two colors, the colors do
       *      not share the same {@link ColorSpace} or do not use a valid one, or {@code positions}
       *      is not {@code null} and has a different length from {@code colors}.
       */
      public LinearGradient(float x0, float y0, float x1, float y1, @NonNull @ColorLong long[] colors,
              @Nullable float[] positions, @NonNull TileMode tile) {
          this(x0, y0, x1, y1, colors.clone(), positions, tile, detectColorSpace(colors));
      }
  
      /**
       * Base constructor. Assumes @param colors is a copy that this object can hold onto,
       * and all colors share @param colorSpace.
       */
      private LinearGradient(float x0, float y0, float x1, float y1,
              @NonNull @ColorLong long[] colors, @Nullable float[] positions, @NonNull TileMode tile,
              @NonNull ColorSpace colorSpace) {
          super(colorSpace);
  
          if (positions != null && colors.length != positions.length) {
              throw new IllegalArgumentException("color and position arrays must be of equal length");
          }
          mX0 = x0;
          mY0 = y0;
          mX1 = x1;
          mY1 = y1;
          mColorLongs = colors;
          mPositions = positions != null ? positions.clone() : null;
          mTileMode = tile;
      }
  
      /**
       * Create a shader that draws a linear gradient along a line.
       *
       * @param x0       The x-coordinate for the start of the gradient line
       * @param y0       The y-coordinate for the start of the gradient line
       * @param x1       The x-coordinate for the end of the gradient line
       * @param y1       The y-coordinate for the end of the gradient line
       * @param color0   The sRGB color at the start of the gradient line.
       * @param color1   The sRGB color at the end of the gradient line.
       * @param tile     The Shader tiling mode
       */
      public LinearGradient(float x0, float y0, float x1, float y1,
              @ColorInt int color0, @ColorInt int color1,
              @NonNull TileMode tile) {
          this(x0, y0, x1, y1, Color.pack(color0), Color.pack(color1), tile);
      }
  
      /**
       * Create a shader that draws a linear gradient along a line.
       *
       * @param x0       The x-coordinate for the start of the gradient line
       * @param y0       The y-coordinate for the start of the gradient line
       * @param x1       The x-coordinate for the end of the gradient line
       * @param y1       The y-coordinate for the end of the gradient line
       * @param color0   The color at the start of the gradient line.
       * @param color1   The color at the end of the gradient line.
       * @param tile     The Shader tiling mode
       *
       * @throws IllegalArgumentException if the colors do
       *      not share the same {@link ColorSpace} or do not use a valid one.
       */
      public LinearGradient(float x0, float y0, float x1, float y1,
              @ColorLong long color0, @ColorLong long color1,
              @NonNull TileMode tile) {
          this(x0, y0, x1, y1, new long[] {color0, color1}, null, tile);
      }
  
      @Override
      long createNativeInstance(long nativeMatrix) {
          return nativeCreate(nativeMatrix, mX0, mY0, mX1, mY1,
                  mColorLongs, mPositions, mTileMode.nativeInt,
                  colorSpace().getNativeInstance());
      }
  
      private native long nativeCreate(long matrix, float x0, float y0, float x1, float y1,
              long[] colors, float[] positions, int tileMode, long colorSpaceHandle);
  }
  