implemented snake sort

app/src/main/java/com/willowtreeapps/spurceexampleapp/fragments/ControlsFragment.java

@@ -51,6 +51,7 @@
 import com.willowtreeapps.spruce.sort.LinearSort;
 import com.willowtreeapps.spruce.sort.RadialSort;
 import com.willowtreeapps.spruce.sort.RandomSort;
+import com.willowtreeapps.spruce.sort.SnakeSort;
 import com.willowtreeapps.spruce.sort.SortFunction;
 import com.willowtreeapps.spurceexampleapp.R;
 import com.willowtreeapps.spurceexampleapp.SpruceActivity;
@@ -69,6 +70,7 @@ public class ControlsFragment extends Fragment implements RadioGroupGridLayout.O
     private static final int LINEAR_SORT = 5;
     private static final int RADIAL_SORT = 6;
     private static final int RANDOM_SORT = 7;
+    private static final int SNAKE_SORT = 8;
 
     private Animator spruceAnimator;
     private SeekBar seekBar;
@@ -139,6 +141,7 @@ public void onClick(View v) {
             @Override
             public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                 switch (position) {
+                    case SNAKE_SORT:
                     case CORNERED_SORT:
                     case INLINE_SORT:
                         linearRadioGroup.setVisibility(View.GONE);
@@ -389,6 +392,13 @@ private void setupSort() {
                 sortFunction = new RandomSort(seekBar.getProgress());
                 codeSample.setText(String.format(getResources().getString(R.string.random_sort_code), seekBar.getProgress()));
                 break;
+            case SNAKE_SORT:
+                sortFunction = new SnakeSort(seekBar.getProgress(), linearReversed.isChecked(), corner);
+                codeSample.setText(String.format(getResources().getString(R.string.snake_sort_code),
+                        seekBar.getProgress(),
+                        String.valueOf(linearReversed.isChecked()),
+                        corner));
+                break;
             default:
                 sortFunction = new DefaultSort(seekBar.getProgress());
                 codeSample.setText(String.format(getResources().getString(R.string.default_sort_code), seekBar.getProgress()));

app/src/main/res/values/sort_functions_array.xml

@@ -31,5 +31,6 @@
         <item>@string/linear_sort</item>
         <item>@string/radial_sort</item>
         <item>@string/random_sort</item>
+        <item>@string/snake_sort</item>
     </string-array>
 </resources>

app/src/main/res/values/strings.xml

@@ -38,6 +38,7 @@
     <string name="linear_sort">Linear Sort</string>
     <string name="radial_sort">Radial Sort</string>
     <string name="random_sort">Random Sort</string>
+    <string name="snake_sort">Snake Sort</string>
     <!-- Linear -->
     <string name="bottom_to_top">Bottom to Top</string>
     <string name="top_to_bottom">Top to Bottom</string>
@@ -82,5 +83,6 @@
     <string name="linear_sort_code">new LinearSort(%1$d, %2$s, LinearSort.Direction.%3$s);</string>
     <string name="radial_sort_code">new RadialSort(%1$d, %2$s, RadialSort.Position.%3$s);</string>
     <string name="random_sort_code">new RandomSort(%1$d);</string>
+    <string name="snake_sort_code">new SnakeSort(%1$d, %2$s, CorneredSort.Corner.%3$s);</string>
     <string name="sort_controls">Sort Controls</string>
 </resources>

lib/src/main/java/com/willowtreeapps/spruce/sort/InlineSort.java

@@ -84,4 +84,4 @@ public int compare(View left, View right) {
         return timedViews;
     }
 
-}
+}

lib/src/main/java/com/willowtreeapps/spruce/sort/SnakeSort.java

@@ -0,0 +1,108 @@
+/*
+ *     Spruce
+ *
+ *     Copyright (c) 2017 WillowTree, Inc.
+ *     Permission is hereby granted, free of charge, to any person obtaining a copy
+ *     of this software and associated documentation files (the "Software"), to deal
+ *     in the Software without restriction, including without limitation the rights
+ *     to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *     copies of the Software, and to permit persons to whom the Software is
+ *     furnished to do so, subject to the following conditions:
+ *     The above copyright notice and this permission notice shall be included in
+ *     all copies or substantial portions of the Software.
+ *     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *     IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *     FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *     AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *     LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *     OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ *     THE SOFTWARE.
+ *
+ */
+
+package com.willowtreeapps.spruce.sort;
+
+import android.graphics.PointF;
+import android.view.View;
+import android.view.ViewGroup;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+
+public class SnakeSort extends CorneredSort {
+
+    private final long interObjectDelay;
+    private final boolean reversed;
+
+    /**
+     * Animate child views from side to side (based on the provided corner parameter), alternating left to right and right to left on each row.
+     *
+     * @param interObjectDelay long delay between objects
+     * @param reversed boolean indicating if the selection is reversed
+     * @param corner {@link com.willowtreeapps.spruce.sort.CorneredSort.Corner Corner} value to start from
+     */
+    public SnakeSort(long interObjectDelay, boolean reversed, Corner corner) {
+        super(interObjectDelay, reversed, corner);
+        this.interObjectDelay = interObjectDelay;
+        this.reversed = reversed;
+    }
+
+    @Override
+    public List<SpruceTimedView> getViewListWithTimeOffsets(ViewGroup parent, List<View> children) {
+        final PointF comparisonPoint = getDistancePoint(parent, children);
+        List<SpruceTimedView> timedViews = new ArrayList<>();
+        long currentTimeOffset = 0;
+
+        // Calculate all possible vertical distances from the point of comparison.
+        final List<Float> verticalDistances = new ArrayList<>();
+        for (View child: children) {
+            float d = Utils.verticalDistance(comparisonPoint, Utils.viewToPoint(child));
+            if (!verticalDistances.contains(d)) {
+                verticalDistances.add(d);
+            }
+        }
+
+        // Sort these so we can find the row index by the vertical distance.
+        Collections.sort(verticalDistances);
+
+        Collections.sort(children, new Comparator<View>() {
+            @Override
+            public int compare(View left, View right) {
+                double leftHorizontalDistance = Utils.horizontalDistance(comparisonPoint, Utils.viewToPoint(left));
+                double leftVerticalDistance = Utils.verticalDistance(comparisonPoint, Utils.viewToPoint(left));
+                double rightHorizontalDistance = Utils.horizontalDistance(comparisonPoint, Utils.viewToPoint(right));
+                double rightVerticalDistance = Utils.verticalDistance(comparisonPoint, Utils.viewToPoint(right));
+
+                // Difference in vertical distance takes priority.
+                if (leftVerticalDistance < rightVerticalDistance) {
+                    return -1;
+                } else if (leftVerticalDistance > rightVerticalDistance) {
+                    return 1;
+                }
+
+                // If the are in the same row, find the row index.
+                int row = verticalDistances.indexOf((float) leftVerticalDistance);
+                if (leftHorizontalDistance < rightHorizontalDistance) {
+                    return row % 2 == 0 ? -1: 1;
+                } else {
+                    return row % 2 == 0 ? 1: -1;
+                }
+            }
+        });
+
+        if (reversed) {
+            Collections.reverse(children);
+        }
+
+        for (View view : children) {
+            timedViews.add(new SpruceTimedView(view, currentTimeOffset));
+            currentTimeOffset += interObjectDelay;
+        }
+
+        return timedViews;
+    }
+
+
+}