content: /*
   * Copyright (C) 2015 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.util;
  
  import com.android.ide.common.rendering.api.LayoutLog;
  import com.android.layoutlib.bridge.Bridge;
  import com.android.layoutlib.bridge.impl.DelegateManager;
  import com.android.tools.layoutlib.annotations.LayoutlibDelegate;
  
  import android.annotation.NonNull;
  import android.graphics.Path_Delegate;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.logging.Level;
  import java.util.logging.Logger;
  
  /**
   * Delegate that provides implementation for native methods in {@link android.util.PathParser}
   * <p/>
   * Through the layoutlib_create tool, selected methods of PathParser have been replaced by calls to
   * methods of the same name in this delegate class.
   *
   * Most of the code has been taken from the implementation in
   * {@code tools/base/sdk-common/src/main/java/com/android/ide/common/vectordrawable/PathParser.java}
   * revision be6fe89a3b686db5a75e7e692a148699973957f3
   */
  public class PathParser_Delegate {
  
      private static final Logger LOGGER = Logger.getLogger("PathParser");
  
      // ---- Builder delegate manager ----
      private static final DelegateManager<PathParser_Delegate> sManager =
              new DelegateManager<PathParser_Delegate>(PathParser_Delegate.class);
  
      // ---- delegate data ----
      @NonNull
      private PathDataNode[] mPathDataNodes;
  
      public static PathParser_Delegate getDelegate(long nativePtr) {
          return sManager.getDelegate(nativePtr);
      }
  
      private PathParser_Delegate(@NonNull PathDataNode[] nodes) {
          mPathDataNodes = nodes;
      }
  
      public PathDataNode[] getPathDataNodes() {
          return mPathDataNodes;
      }
  
      @LayoutlibDelegate
      /*package*/ static void nParseStringForPath(long pathPtr, @NonNull String pathString, int
              stringLength) {
          Path_Delegate path_delegate = Path_Delegate.getDelegate(pathPtr);
          if (path_delegate == null) {
              return;
          }
          assert pathString.length() == stringLength;
          PathDataNode.nodesToPath(createNodesFromPathData(pathString), path_delegate);
      }
  
      @LayoutlibDelegate
      /*package*/ static void nCreatePathFromPathData(long outPathPtr, long pathData) {
          Path_Delegate path_delegate = Path_Delegate.getDelegate(outPathPtr);
          PathParser_Delegate source = sManager.getDelegate(outPathPtr);
          if (source == null || path_delegate == null) {
              return;
          }
          PathDataNode.nodesToPath(source.mPathDataNodes, path_delegate);
      }
  
      @LayoutlibDelegate
      /*package*/ static long nCreateEmptyPathData() {
          PathParser_Delegate newDelegate = new PathParser_Delegate(new PathDataNode[0]);
          return sManager.addNewDelegate(newDelegate);
      }
  
      @LayoutlibDelegate
      /*package*/ static long nCreatePathData(long nativePtr) {
          PathParser_Delegate source = sManager.getDelegate(nativePtr);
          if (source == null) {
              return 0;
          }
          PathParser_Delegate dest = new PathParser_Delegate(deepCopyNodes(source.mPathDataNodes));
          return sManager.addNewDelegate(dest);
      }
  
      @LayoutlibDelegate
      /*package*/ static long nCreatePathDataFromString(@NonNull String pathString,
              int stringLength) {
          assert pathString.length() == stringLength : "Inconsistent path string length.";
          PathDataNode[] nodes = createNodesFromPathData(pathString);
          PathParser_Delegate delegate = new PathParser_Delegate(nodes);
          return sManager.addNewDelegate(delegate);
  
      }
  
      @LayoutlibDelegate
      /*package*/ static boolean nInterpolatePathData(long outDataPtr, long fromDataPtr,
              long toDataPtr, float fraction) {
          PathParser_Delegate out = sManager.getDelegate(outDataPtr);
          PathParser_Delegate from = sManager.getDelegate(fromDataPtr);
          PathParser_Delegate to = sManager.getDelegate(toDataPtr);
          if (out == null || from == null || to == null) {
              return false;
          }
          int length = from.mPathDataNodes.length;
          if (length != to.mPathDataNodes.length) {
              Bridge.getLog().error(LayoutLog.TAG_BROKEN,
                      "Cannot interpolate path data with different lengths (from " + length + " to " +
                              to.mPathDataNodes.length + ").", null);
              return false;
          }
          if (out.mPathDataNodes.length != length) {
              out.mPathDataNodes = new PathDataNode[length];
          }
          for (int i = 0; i < length; i++) {
              if (out.mPathDataNodes[i] == null) {
                  out.mPathDataNodes[i] = new PathDataNode(from.mPathDataNodes[i]);
              }
              out.mPathDataNodes[i].interpolatePathDataNode(from.mPathDataNodes[i],
                          to.mPathDataNodes[i], fraction);
          }
          return true;
      }
  
      @LayoutlibDelegate
      /*package*/ static void nFinalize(long nativePtr) {
          sManager.removeJavaReferenceFor(nativePtr);
      }
  
      @LayoutlibDelegate
      /*package*/ static boolean nCanMorph(long fromDataPtr, long toDataPtr) {
          PathParser_Delegate fromPath = PathParser_Delegate.getDelegate(fromDataPtr);
          PathParser_Delegate toPath = PathParser_Delegate.getDelegate(toDataPtr);
          if (fromPath == null || toPath == null || fromPath.getPathDataNodes() == null || toPath
                  .getPathDataNodes() == null) {
              return true;
          }
          return PathParser_Delegate.canMorph(fromPath.getPathDataNodes(), toPath.getPathDataNodes());
      }
  
      @LayoutlibDelegate
      /*package*/ static void nSetPathData(long outDataPtr, long fromDataPtr) {
          PathParser_Delegate out = sManager.getDelegate(outDataPtr);
          PathParser_Delegate from = sManager.getDelegate(fromDataPtr);
          if (from == null || out == null) {
              return;
          }
          out.mPathDataNodes = deepCopyNodes(from.mPathDataNodes);
      }
  
      /**
       * @param pathData The string representing a path, the same as "d" string in svg file.
       *
       * @return an array of the PathDataNode.
       */
      @NonNull
      public static PathDataNode[] createNodesFromPathData(@NonNull String pathData) {
          int start = 0;
          int end = 1;
  
          ArrayList<PathDataNode> list = new ArrayList<PathDataNode>();
          while (end < pathData.length()) {
              end = nextStart(pathData, end);
              String s = pathData.substring(start, end).trim();
              if (s.length() > 0) {
                  float[] val = getFloats(s);
                  addNode(list, s.charAt(0), val);
              }
  
              start = end;
              end++;
          }
          if ((end - start) == 1 && start < pathData.length()) {
              addNode(list, pathData.charAt(start), new float[0]);
          }
          return list.toArray(new PathDataNode[list.size()]);
      }
  
      /**
       * @param source The array of PathDataNode to be duplicated.
       *
       * @return a deep copy of the <code>source</code>.
       */
      @NonNull
      public static PathDataNode[] deepCopyNodes(@NonNull PathDataNode[] source) {
          PathDataNode[] copy = new PathDataNode[source.length];
          for (int i = 0; i < source.length; i++) {
              copy[i] = new PathDataNode(source[i]);
          }
          return copy;
      }
  
      /**
       * @param nodesFrom The source path represented in an array of PathDataNode
       * @param nodesTo The target path represented in an array of PathDataNode
       * @return whether the <code>nodesFrom</code> can morph into <code>nodesTo</code>
       */
      public static boolean canMorph(PathDataNode[] nodesFrom, PathDataNode[] nodesTo) {
          if (nodesFrom == null || nodesTo == null) {
              return false;
          }
  
          if (nodesFrom.length != nodesTo.length) {
              return false;
          }
  
          for (int i = 0; i < nodesFrom.length; i ++) {
              if (nodesFrom[i].mType != nodesTo[i].mType
                      || nodesFrom[i].mParams.length != nodesTo[i].mParams.length) {
                  return false;
              }
          }
          return true;
      }
  
      /**
       * Update the target's data to match the source.
       * Before calling this, make sure canMorph(target, source) is true.
       *
       * @param target The target path represented in an array of PathDataNode
       * @param source The source path represented in an array of PathDataNode
       */
      public static void updateNodes(PathDataNode[] target, PathDataNode[] source) {
          for (int i = 0; i < source.length; i ++) {
              target[i].mType = source[i].mType;
              for (int j = 0; j < source[i].mParams.length; j ++) {
                  target[i].mParams[j] = source[i].mParams[j];
              }
          }
      }
  
      private static int nextStart(@NonNull String s, int end) {
          char c;
  
          while (end < s.length()) {
              c = s.charAt(end);
              // Note that 'e' or 'E' are not valid path commands, but could be
              // used for floating point numbers' scientific notation.
              // Therefore, when searching for next command, we should ignore 'e'
              // and 'E'.
              if ((((c - 'A') * (c - 'Z') <= 0) || ((c - 'a') * (c - 'z') <= 0))
                      && c != 'e' && c != 'E') {
                  return end;
              }
              end++;
          }
          return end;
      }
  
      /**
       * Calculate the position of the next comma or space or negative sign
       *
       * @param s the string to search
       * @param start the position to start searching
       * @param result the result of the extraction, including the position of the the starting
       * position of next number, whether it is ending with a '-'.
       */
      private static void extract(@NonNull String s, int start, @NonNull ExtractFloatResult result) {
          // Now looking for ' ', ',', '.' or '-' from the start.
          int currentIndex = start;
          boolean foundSeparator = false;
          result.mEndWithNegOrDot = false;
          boolean secondDot = false;
          boolean isExponential = false;
          for (; currentIndex < s.length(); currentIndex++) {
              boolean isPrevExponential = isExponential;
              isExponential = false;
              char currentChar = s.charAt(currentIndex);
              switch (currentChar) {
                  case ' ':
                  case ',':
                  case '\t':
                  case '\n':
                      foundSeparator = true;
                      break;
                  case '-':
                      // The negative sign following a 'e' or 'E' is not a separator.
                      if (currentIndex != start && !isPrevExponential) {
                          foundSeparator = true;
                          result.mEndWithNegOrDot = true;
                      }
                      break;
                  case '.':
                      if (!secondDot) {
                          secondDot = true;
                      } else {
                          // This is the second dot, and it is considered as a separator.
                          foundSeparator = true;
                          result.mEndWithNegOrDot = true;
                      }
                      break;
                  case 'e':
                  case 'E':
                      isExponential = true;
                      break;
              }
              if (foundSeparator) {
                  break;
              }
          }
          // When there is nothing found, then we put the end position to the end
          // of the string.
          result.mEndPosition = currentIndex;
      }
  
      /**
       * Parse the floats in the string. This is an optimized version of
       * parseFloat(s.split(",|\\s"));
       *
       * @param s the string containing a command and list of floats
       *
       * @return array of floats
       */
      @NonNull
      private static float[] getFloats(@NonNull String s) {
          if (s.charAt(0) == 'z' || s.charAt(0) == 'Z') {
              return new float[0];
          }
          try {
              float[] results = new float[s.length()];
              int count = 0;
              int startPosition = 1;
              int endPosition;
  
              ExtractFloatResult result = new ExtractFloatResult();
              int totalLength = s.length();
  
              // The startPosition should always be the first character of the
              // current number, and endPosition is the character after the current
              // number.
              while (startPosition < totalLength) {
                  extract(s, startPosition, result);
                  endPosition = result.mEndPosition;
  
                  if (startPosition < endPosition) {
                      results[count++] = Float.parseFloat(
                              s.substring(startPosition, endPosition));
                  }
  
                  if (result.mEndWithNegOrDot) {
                      // Keep the '-' or '.' sign with next number.
                      startPosition = endPosition;
                  } else {
                      startPosition = endPosition + 1;
                  }
              }
              return Arrays.copyOf(results, count);
          } catch (NumberFormatException e) {
              assert false : "error in parsing \"" + s + "\"" + e;
              return new float[0];
          }
      }
  
  
      private static void addNode(@NonNull ArrayList<PathDataNode> list, char cmd,
              @NonNull float[] val) {
          list.add(new PathDataNode(cmd, val));
      }
  
      private static class ExtractFloatResult {
          // We need to return the position of the next separator and whether the
          // next float starts with a '-' or a '.'.
          private int mEndPosition;
          private boolean mEndWithNegOrDot;
      }
  
      /**
       * Each PathDataNode represents one command in the "d" attribute of the svg file. An array of
       * PathDataNode can represent the whole "d" attribute.
       */
      public static class PathDataNode {
          private char mType;
          @NonNull
          private float[] mParams;
  
          private PathDataNode(char type, @NonNull float[] params) {
              mType = type;
              mParams = params;
          }
  
          public char getType() {
              return mType;
          }
  
          @NonNull
          public float[] getParams() {
              return mParams;
          }
  
          private PathDataNode(@NonNull PathDataNode n) {
              mType = n.mType;
              mParams = Arrays.copyOf(n.mParams, n.mParams.length);
          }
  
          /**
           * Convert an array of PathDataNode to Path. Reset the passed path as needed before
           * calling this method.
           *
           * @param node The source array of PathDataNode.
           * @param path The target Path object.
           */
          public static void nodesToPath(@NonNull PathDataNode[] node, @NonNull Path_Delegate path) {
              float[] current = new float[6];
              char previousCommand = 'm';
              //noinspection ForLoopReplaceableByForEach
              for (int i = 0; i < node.length; i++) {
                  addCommand(path, current, previousCommand, node[i].mType, node[i].mParams);
                  previousCommand = node[i].mType;
              }
          }
  
          /**
           * The current PathDataNode will be interpolated between the <code>nodeFrom</code> and
           * <code>nodeTo</code> according to the <code>fraction</code>.
           *
           * @param nodeFrom The start value as a PathDataNode.
           * @param nodeTo The end value as a PathDataNode
           * @param fraction The fraction to interpolate.
           */
          private void interpolatePathDataNode(@NonNull PathDataNode nodeFrom,
                  @NonNull PathDataNode nodeTo, float fraction) {
              for (int i = 0; i < nodeFrom.mParams.length; i++) {
                  mParams[i] = nodeFrom.mParams[i] * (1 - fraction)
                          + nodeTo.mParams[i] * fraction;
              }
          }
  
          @SuppressWarnings("PointlessArithmeticExpression")
          private static void addCommand(@NonNull Path_Delegate path, float[] current,
                  char previousCmd, char cmd, @NonNull float[] val) {
  
              int incr = 2;
              float currentX = current[0];
              float currentY = current[1];
              float ctrlPointX = current[2];
              float ctrlPointY = current[3];
              float currentSegmentStartX = current[4];
              float currentSegmentStartY = current[5];
              float reflectiveCtrlPointX;
              float reflectiveCtrlPointY;
  
              switch (cmd) {
                  case 'z':
                  case 'Z':
                      path.close();
                      // Path is closed here, but we need to move the pen to the
                      // closed position. So we cache the segment's starting position,
                      // and restore it here.
                      currentX = currentSegmentStartX;
                      currentY = currentSegmentStartY;
                      ctrlPointX = currentSegmentStartX;
                      ctrlPointY = currentSegmentStartY;
                      path.moveTo(currentX, currentY);
                      break;
                  case 'm':
                  case 'M':
                  case 'l':
                  case 'L':
                  case 't':
                  case 'T':
                      incr = 2;
                      break;
                  case 'h':
                  case 'H':
                  case 'v':
                  case 'V':
                      incr = 1;
                      break;
                  case 'c':
                  case 'C':
                      incr = 6;
                      break;
                  case 's':
                  case 'S':
                  case 'q':
                  case 'Q':
                      incr = 4;
                      break;
                  case 'a':
                  case 'A':
                      incr = 7;
                      break;
              }
  
              for (int k = 0; k < val.length; k += incr) {
                  switch (cmd) {
                      case 'm': // moveto - Start a new sub-path (relative)
                          currentX += val[k + 0];
                          currentY += val[k + 1];
  
                          if (k > 0) {
                              // According to the spec, if a moveto is followed by multiple
                              // pairs of coordinates, the subsequent pairs are treated as
                              // implicit lineto commands.
                              path.rLineTo(val[k + 0], val[k + 1]);
                          } else {
                              path.rMoveTo(val[k + 0], val[k + 1]);
                              currentSegmentStartX = currentX;
                              currentSegmentStartY = currentY;
                          }
                          break;
                      case 'M': // moveto - Start a new sub-path
                          currentX = val[k + 0];
                          currentY = val[k + 1];
  
                          if (k > 0) {
                              // According to the spec, if a moveto is followed by multiple
                              // pairs of coordinates, the subsequent pairs are treated as
                              // implicit lineto commands.
                              path.lineTo(val[k + 0], val[k + 1]);
                          } else {
                              path.moveTo(val[k + 0], val[k + 1]);
                              currentSegmentStartX = currentX;
                              currentSegmentStartY = currentY;
                          }
                          break;
                      case 'l': // lineto - Draw a line from the current point (relative)
                          path.rLineTo(val[k + 0], val[k + 1]);
                          currentX += val[k + 0];
                          currentY += val[k + 1];
                          break;
                      case 'L': // lineto - Draw a line from the current point
                          path.lineTo(val[k + 0], val[k + 1]);
                          currentX = val[k + 0];
                          currentY = val[k + 1];
                          break;
                      case 'h': // horizontal lineto - Draws a horizontal line (relative)
                          path.rLineTo(val[k + 0], 0);
                          currentX += val[k + 0];
                          break;
                      case 'H': // horizontal lineto - Draws a horizontal line
                          path.lineTo(val[k + 0], currentY);
                          currentX = val[k + 0];
                          break;
                      case 'v': // vertical lineto - Draws a vertical line from the current point (r)
                          path.rLineTo(0, val[k + 0]);
                          currentY += val[k + 0];
                          break;
                      case 'V': // vertical lineto - Draws a vertical line from the current point
                          path.lineTo(currentX, val[k + 0]);
                          currentY = val[k + 0];
                          break;
                      case 'c': // curveto - Draws a cubic Bézier curve (relative)
                          path.rCubicTo(val[k + 0], val[k + 1], val[k + 2], val[k + 3],
                                  val[k + 4], val[k + 5]);
  
                          ctrlPointX = currentX + val[k + 2];
                          ctrlPointY = currentY + val[k + 3];
                          currentX += val[k + 4];
                          currentY += val[k + 5];
  
                          break;
                      case 'C': // curveto - Draws a cubic Bézier curve
                          path.cubicTo(val[k + 0], val[k + 1], val[k + 2], val[k + 3],
                                  val[k + 4], val[k + 5]);
                          currentX = val[k + 4];
                          currentY = val[k + 5];
                          ctrlPointX = val[k + 2];
                          ctrlPointY = val[k + 3];
                          break;
                      case 's': // smooth curveto - Draws a cubic Bézier curve (reflective cp)
                          reflectiveCtrlPointX = 0;
                          reflectiveCtrlPointY = 0;
                          if (previousCmd == 'c' || previousCmd == 's'
                                  || previousCmd == 'C' || previousCmd == 'S') {
                              reflectiveCtrlPointX = currentX - ctrlPointX;
                              reflectiveCtrlPointY = currentY - ctrlPointY;
                          }
                          path.rCubicTo(reflectiveCtrlPointX, reflectiveCtrlPointY,
                                  val[k + 0], val[k + 1],
                                  val[k + 2], val[k + 3]);
  
                          ctrlPointX = currentX + val[k + 0];
                          ctrlPointY = currentY + val[k + 1];
                          currentX += val[k + 2];
                          currentY += val[k + 3];
                          break;
                      case 'S': // shorthand/smooth curveto Draws a cubic Bézier curve(reflective cp)
                          reflectiveCtrlPointX = currentX;
                          reflectiveCtrlPointY = currentY;
                          if (previousCmd == 'c' || previousCmd == 's'
                                  || previousCmd == 'C' || previousCmd == 'S') {
                              reflectiveCtrlPointX = 2 * currentX - ctrlPointX;
                              reflectiveCtrlPointY = 2 * currentY - ctrlPointY;
                          }
                          path.cubicTo(reflectiveCtrlPointX, reflectiveCtrlPointY,
                                  val[k + 0], val[k + 1], val[k + 2], val[k + 3]);
                          ctrlPointX = val[k + 0];
                          ctrlPointY = val[k + 1];
                          currentX = val[k + 2];
                          currentY = val[k + 3];
                          break;
                      case 'q': // Draws a quadratic Bézier (relative)
                          path.rQuadTo(val[k + 0], val[k + 1], val[k + 2], val[k + 3]);
                          ctrlPointX = currentX + val[k + 0];
                          ctrlPointY = currentY + val[k + 1];
                          currentX += val[k + 2];
                          currentY += val[k + 3];
                          break;
                      case 'Q': // Draws a quadratic Bézier
                          path.quadTo(val[k + 0], val[k + 1], val[k + 2], val[k + 3]);
                          ctrlPointX = val[k + 0];
                          ctrlPointY = val[k + 1];
                          currentX = val[k + 2];
                          currentY = val[k + 3];
                          break;
                      case 't': // Draws a quadratic Bézier curve(reflective control point)(relative)
                          reflectiveCtrlPointX = 0;
                          reflectiveCtrlPointY = 0;
                          if (previousCmd == 'q' || previousCmd == 't'
                                  || previousCmd == 'Q' || previousCmd == 'T') {
                              reflectiveCtrlPointX = currentX - ctrlPointX;
                              reflectiveCtrlPointY = currentY - ctrlPointY;
                          }
                          path.rQuadTo(reflectiveCtrlPointX, reflectiveCtrlPointY,
                                  val[k + 0], val[k + 1]);
                          ctrlPointX = currentX + reflectiveCtrlPointX;
                          ctrlPointY = currentY + reflectiveCtrlPointY;
                          currentX += val[k + 0];
                          currentY += val[k + 1];
                          break;
                      case 'T': // Draws a quadratic Bézier curve (reflective control point)
                          reflectiveCtrlPointX = currentX;
                          reflectiveCtrlPointY = currentY;
                          if (previousCmd == 'q' || previousCmd == 't'
                                  || previousCmd == 'Q' || previousCmd == 'T') {
                              reflectiveCtrlPointX = 2 * currentX - ctrlPointX;
                              reflectiveCtrlPointY = 2 * currentY - ctrlPointY;
                          }
                          path.quadTo(reflectiveCtrlPointX, reflectiveCtrlPointY,
                                  val[k + 0], val[k + 1]);
                          ctrlPointX = reflectiveCtrlPointX;
                          ctrlPointY = reflectiveCtrlPointY;
                          currentX = val[k + 0];
                          currentY = val[k + 1];
                          break;
                      case 'a': // Draws an elliptical arc
                          // (rx ry x-axis-rotation large-arc-flag sweep-flag x y)
                          drawArc(path,
                                  currentX,
                                  currentY,
                                  val[k + 5] + currentX,
                                  val[k + 6] + currentY,
                                  val[k + 0],
                                  val[k + 1],
                                  val[k + 2],
                                  val[k + 3] != 0,
                                  val[k + 4] != 0);
                          currentX += val[k + 5];
                          currentY += val[k + 6];
                          ctrlPointX = currentX;
                          ctrlPointY = currentY;
                          break;
                      case 'A': // Draws an elliptical arc
                          drawArc(path,
                                  currentX,
                                  currentY,
                                  val[k + 5],
                                  val[k + 6],
                                  val[k + 0],
                                  val[k + 1],
                                  val[k + 2],
                                  val[k + 3] != 0,
                                  val[k + 4] != 0);
                          currentX = val[k + 5];
                          currentY = val[k + 6];
                          ctrlPointX = currentX;
                          ctrlPointY = currentY;
                          break;
                  }
                  previousCmd = cmd;
              }
              current[0] = currentX;
              current[1] = currentY;
              current[2] = ctrlPointX;
              current[3] = ctrlPointY;
              current[4] = currentSegmentStartX;
              current[5] = currentSegmentStartY;
          }
  
          private static void drawArc(@NonNull Path_Delegate p, float x0, float y0, float x1,
                  float y1, float a, float b, float theta, boolean isMoreThanHalf,
                  boolean isPositiveArc) {
  
              LOGGER.log(Level.FINE, "(" + x0 + "," + y0 + ")-(" + x1 + "," + y1
                      + ") {" + a + " " + b + "}");
          /* Convert rotation angle from degrees to radians */
              double thetaD = theta * Math.PI / 180.0f;
          /* Pre-compute rotation matrix entries */
              double cosTheta = Math.cos(thetaD);
              double sinTheta = Math.sin(thetaD);
          /* Transform (x0, y0) and (x1, y1) into unit space */
          /* using (inverse) rotation, followed by (inverse) scale */
              double x0p = (x0 * cosTheta + y0 * sinTheta) / a;
              double y0p = (-x0 * sinTheta + y0 * cosTheta) / b;
              double x1p = (x1 * cosTheta + y1 * sinTheta) / a;
              double y1p = (-x1 * sinTheta + y1 * cosTheta) / b;
              LOGGER.log(Level.FINE, "unit space (" + x0p + "," + y0p + ")-(" + x1p
                      + "," + y1p + ")");
          /* Compute differences and averages */
              double dx = x0p - x1p;
              double dy = y0p - y1p;
              double xm = (x0p + x1p) / 2;
              double ym = (y0p + y1p) / 2;
          /* Solve for intersecting unit circles */
              double dsq = dx * dx + dy * dy;
              if (dsq == 0.0) {
                  LOGGER.log(Level.FINE, " Points are coincident");
                  return; /* Points are coincident */
              }
              double disc = 1.0 / dsq - 1.0 / 4.0;
              if (disc < 0.0) {
                  LOGGER.log(Level.FINE, "Points are too far apart " + dsq);
                  float adjust = (float) (Math.sqrt(dsq) / 1.99999);
                  drawArc(p, x0, y0, x1, y1, a * adjust, b * adjust, theta,
                          isMoreThanHalf, isPositiveArc);
                  return; /* Points are too far apart */
              }
              double s = Math.sqrt(disc);
              double sdx = s * dx;
              double sdy = s * dy;
              double cx;
              double cy;
              if (isMoreThanHalf == isPositiveArc) {
                  cx = xm - sdy;
                  cy = ym + sdx;
              } else {
                  cx = xm + sdy;
                  cy = ym - sdx;
              }
  
              double eta0 = Math.atan2((y0p - cy), (x0p - cx));
              LOGGER.log(Level.FINE, "eta0 = Math.atan2( " + (y0p - cy) + " , "
                      + (x0p - cx) + ") = " + Math.toDegrees(eta0));
  
              double eta1 = Math.atan2((y1p - cy), (x1p - cx));
              LOGGER.log(Level.FINE, "eta1 = Math.atan2( " + (y1p - cy) + " , "
                      + (x1p - cx) + ") = " + Math.toDegrees(eta1));
              double sweep = (eta1 - eta0);
              if (isPositiveArc != (sweep >= 0)) {
                  if (sweep > 0) {
                      sweep -= 2 * Math.PI;
                  } else {
                      sweep += 2 * Math.PI;
                  }
              }
  
              cx *= a;
              cy *= b;
              double tcx = cx;
              cx = cx * cosTheta - cy * sinTheta;
              cy = tcx * sinTheta + cy * cosTheta;
              LOGGER.log(
                      Level.FINE,
                      "cx, cy, a, b, x0, y0, thetaD, eta0, sweep = " + cx + " , "
                              + cy + " , " + a + " , " + b + " , " + x0 + " , " + y0
                              + " , " + Math.toDegrees(thetaD) + " , "
                              + Math.toDegrees(eta0) + " , " + Math.toDegrees(sweep));
  
              arcToBezier(p, cx, cy, a, b, x0, y0, thetaD, eta0, sweep);
          }
  
          /**
           * Converts an arc to cubic Bezier segments and records them in p.
           *
           * @param p The target for the cubic Bezier segments
           * @param cx The x coordinate center of the ellipse
           * @param cy The y coordinate center of the ellipse
           * @param a The radius of the ellipse in the horizontal direction
           * @param b The radius of the ellipse in the vertical direction
           * @param e1x E(eta1) x coordinate of the starting point of the arc
           * @param e1y E(eta2) y coordinate of the starting point of the arc
           * @param theta The angle that the ellipse bounding rectangle makes with the horizontal
           * plane
           * @param start The start angle of the arc on the ellipse
           * @param sweep The angle (positive or negative) of the sweep of the arc on the ellipse
           */
          private static void arcToBezier(@NonNull Path_Delegate p, double cx, double cy, double a,
                  double b, double e1x, double e1y, double theta, double start,
                  double sweep) {
              // Taken from equations at:
              // http://spaceroots.org/documents/ellipse/node8.html
              // and http://www.spaceroots.org/documents/ellipse/node22.html
              // Maximum of 45 degrees per cubic Bezier segment
              int numSegments = (int) Math.ceil(Math.abs(sweep * 4 / Math.PI));
  
  
              double eta1 = start;
              double cosTheta = Math.cos(theta);
              double sinTheta = Math.sin(theta);
              double cosEta1 = Math.cos(eta1);
              double sinEta1 = Math.sin(eta1);
              double ep1x = (-a * cosTheta * sinEta1) - (b * sinTheta * cosEta1);
              double ep1y = (-a * sinTheta * sinEta1) + (b * cosTheta * cosEta1);
  
              double anglePerSegment = sweep / numSegments;
              for (int i = 0; i < numSegments; i++) {
                  double eta2 = eta1 + anglePerSegment;
                  double sinEta2 = Math.sin(eta2);
                  double cosEta2 = Math.cos(eta2);
                  double e2x = cx + (a * cosTheta * cosEta2)
                          - (b * sinTheta * sinEta2);
                  double e2y = cy + (a * sinTheta * cosEta2)
                          + (b * cosTheta * sinEta2);
                  double ep2x = -a * cosTheta * sinEta2 - b * sinTheta * cosEta2;
                  double ep2y = -a * sinTheta * sinEta2 + b * cosTheta * cosEta2;
                  double tanDiff2 = Math.tan((eta2 - eta1) / 2);
                  double alpha = Math.sin(eta2 - eta1)
                          * (Math.sqrt(4 + (3 * tanDiff2 * tanDiff2)) - 1) / 3;
                  double q1x = e1x + alpha * ep1x;
                  double q1y = e1y + alpha * ep1y;
                  double q2x = e2x - alpha * ep2x;
                  double q2y = e2y - alpha * ep2y;
  
                  p.cubicTo((float) q1x,
                          (float) q1y,
                          (float) q2x,
                          (float) q2y,
                          (float) e2x,
                          (float) e2y);
                  eta1 = eta2;
                  e1x = e2x;
                  e1y = e2y;
                  ep1x = ep2x;
                  ep1y = ep2y;
              }
          }
      }
  }
  