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foudations/mogo-commons/src/main/java/com/mogo/commons/utils/MortonCode.java

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+package com.mogo.commons.utils;
+
+import java.text.DecimalFormat;
+
+/**
+ * 莫顿编码
+ *
+ * @author linyang
+ * @since 2020.07.09
+ */
+public class MortonCode {
+
+    /**
+     * morton 转 经纬度 时的中间常量
+     */
+    private static final long NDS_180_DEGREES = 0x7fffffff;
+
+    /**
+     * morton 转 经纬度 时的中间常量
+     */
+    private static final long NDS_360_DEGREES = 4294967295L;
+
+    /**
+     * morton 转 经纬度 时的中间常量
+     */
+    private static final long NDS_90_DEGREES = 0x3fffffff;
+
+    /**
+     * 经纬度转 morton 时的中间常量
+     */
+    private static final double RULE_MORTON = Math.pow( 2, 32 ) / 360;
+
+    /**
+     * morton 转 经纬度 时的中间常量
+     */
+    private static final double RULE_MORTON_TO_LONLAT = 360.0 / Math.pow( 2, 32 );
+
+    /**
+     * @param lon
+     * @param lat
+     * @return
+     */
+    public static long wrapEncodeMorton( Double lon, Double lat ) {
+        DecimalFormat decimalFormat = new DecimalFormat( "#.######" );
+        return encodeMorton( Double.valueOf( decimalFormat.format( lon ) ),
+                Double.valueOf( decimalFormat.format( lat ) ) );
+    }
+
+    /**
+     * 编码 morton code
+     *
+     * @param lon
+     * @param lat
+     * @return
+     */
+    public static long encodeMorton( Double lon, Double lat ) {
+
+        Long bit = 1L;
+        long mortonCode = 0L;
+        long x = ( long ) ( lon * RULE_MORTON );
+        long y = ( long ) ( lat * RULE_MORTON );
+
+        if ( y < 0 ) {
+            y += 0x7FFFFFFF;
+        }
+        y = y << 1;
+        for ( int i = 0; i < 32; i++ ) {
+            // x-part
+            mortonCode = mortonCode | ( x & bit );
+            x = x << 1;
+            bit = bit << 1;
+            // y-part
+            mortonCode = mortonCode | ( y & bit );
+            y = y << 1;
+            bit = bit << 1;
+        }
+
+        return mortonCode;
+    }
+
+    /**
+     * 将莫顿码解码为坐标
+     *
+     * @param mortonCode
+     * @return
+     */
+    public static double[] decodeMorton( long mortonCode ) {
+        long[] midPoint = mortonCodeToCoord( mortonCode );
+        normalizeCoord( midPoint );
+        double[] point = new double[2];
+
+        // 将经纬度长整数转化为 浮点类型
+        point[0] = midPoint[0] * RULE_MORTON_TO_LONLAT;
+        point[1] = midPoint[1] * RULE_MORTON_TO_LONLAT;
+        return point;
+    }
+
+    /**
+     * 莫顿码分别拆解为 编码后的经纬度长整数
+     *
+     * @param mortonCode
+     * @return
+     */
+    private static long[] mortonCodeToCoord( long mortonCode ) {
+        long bit = 1L;
+        long[] longPoint = new long[2];
+
+        for ( int i = 0; i < 32; i++ ) {
+            longPoint[0] |= mortonCode & bit;
+            mortonCode >>= 1;
+            longPoint[1] |= mortonCode & bit;
+            bit <<= 1;
+        }
+        return longPoint;
+    }
+
+    /**
+     * 对编码后的经纬度长整数进行解码
+     *
+     * @param midPoint
+     */
+    private static void normalizeCoord( long[] midPoint ) {
+        // if x > 180 degrees, then subtract 360 degrees
+        if ( midPoint[0] > NDS_180_DEGREES ) {
+            midPoint[0] -=
+                    NDS_360_DEGREES + 1;  // add 1 because 0 must be counted as well
+        } else if ( midPoint[0] < -NDS_180_DEGREES )  // if x < 180 , x += 360
+        {
+            midPoint[0] +=
+                    NDS_360_DEGREES + 1;  // add 1 because 0 must be counted as well
+        }
+
+        // if y > 90 degrees, then subtract 180 degrees
+        if ( midPoint[1] > NDS_90_DEGREES ) {
+            midPoint[1] -=
+                    NDS_180_DEGREES + 1;  // add 1 because 0 must be counted as well
+        } else if ( midPoint[1] < -NDS_90_DEGREES )  // if y < 90, y += 180
+        {
+            midPoint[1] +=
+                    NDS_180_DEGREES + 1;  // add 1 because 0 must be counted as well
+        }
+        return;
+    }
+
+
+    public static void main( String[] args ) {
+        System.out.println( encodeMorton( 116.39584, 39.98152 ) );
+    }
+}