Add implementation comment for binary reader.

This commit is contained in:
Holt59 2018-03-04 21:41:47 +01:00
parent a1be0fc586
commit e522eaa728

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@ -26,39 +26,6 @@ public class BinaryGraphReaderInsa2018 extends BinaryReader implements GraphRead
// Length of the map id field (in bytes)
protected static final int MAP_ID_FIELD_LENGTH = 32;
/*
* 4 bits are associated to each type of vehicle, these 4 bits represents the
* type of access (see below).
*
* Note: The highest 4 bits of the long are not used, for compatibility issue
* (unsigned/signed... ).
*/
// @formatter:off
// These masks indicates which bit should be set for the access value.
public static final long
MASK_NO = 0x0L, // *=no,
MASK_YES = 0x111111111111111L, // *=yes
MASK_PRIVATE = 0x222222222222222L, // *=private
MASK_DESTINATION = 0x333333333333333L, // *=destination
MASK_DELIVERY = 0x444444444444444L, // *=delivery
MASK_CUSTOMERS = 0x555555555555555L, // *=customers,
MASK_FORESTRY = 0x666666666666666L, // *=forestry,*=agricultural
MASK_UNKNOWN = 0xfffffffffffffffL;
// These masks indicates which parts of the long should be set for each type of
// vehicle
public static final long
MASK_FOOT = 0x00000000000000fL, // foot=*
MASK_BICYCLE = 0x000000000000f00L, // bicycle=*
MASK_SMALL_MOTORCYCLE = 0x00000000000f000L, // moped,mofa=*
MASK_AGRICULTURAL = 0x0000000000f0000L, // agricultural=*
MASK_MOTORCYCLE = 0x000000000f00000L, // motorcycle=*
MASK_MOTORCAR = 0x00000000f000000L, // motorcar=*
MASK_HEAVY_GOODS = 0x0000000f0000000L, // motorcar=*
MASK_PUBLIC_TRANSPORT = 0x0000f0000000000L; // psv,bus,minibus,share_taxi=*
// @formatter:on
/**
* Create a new access information by parsing the given value (V6 version).
*
@ -66,10 +33,21 @@ public class BinaryGraphReaderInsa2018 extends BinaryReader implements GraphRead
* @return
*/
protected static AccessRestrictions toAccessInformationV7(final long access) {
// See the following for more information:
// https://github.com/Holt59/OSM2Graph/blob/master/src/main/org/laas/osm2graph/model/AccessData.java
// The order of values inside this array is VERY IMPORTANT: For allRestrictions,
// the order correspond to the 4 bits value (i.e. FORBIDDEN is 0 or PRIVATE is
// 2) - UKNOWN is not included because value above 6 (FORESTRY) are all
// considered unknown.
final AccessRestriction[] allRestrictions = new AccessRestriction[] { AccessRestriction.FORBIDDEN,
AccessRestriction.ALLOWED, AccessRestriction.PRIVATE, AccessRestriction.DESTINATION,
AccessRestriction.DELIVERY, AccessRestriction.CUSTOMERS, AccessRestriction.FORESTRY };
// The order of values inside this array is VERY IMPORTANT: The order is such
// that each 4-bits group of the long value is processed in the correct order,
// i.e. FOOT is processed first (4 lowest bits), and so on.
final AccessMode[] allModes = new AccessMode[] { AccessMode.FOOT, null, AccessMode.BICYCLE,
AccessMode.SMALL_MOTORCYCLE, AccessMode.AGRICULTURAL, AccessMode.MOTORCYCLE, AccessMode.MOTORCAR,
AccessMode.HEAVY_GOODS, null, AccessMode.PUBLIC_TRANSPORT };