Complex Properties Overhaul

3.0/vector_tile.proto

@@ -44,6 +44,46 @@ message Tile {
                 // A detailed description on geometry encoding is located in 
                 // section 4.3 of the specification.
                 repeated uint32 geometry = 4 [ packed = true ];
+
+                // Properties replace existing tags field and
+                // uses the properties field instead. This would only be used if version
+                // for a layer is 3 or greater and tags should not be used at that point
+                //
+                // The properties field is much like the tags value in the it is two integers
+                // pairs that reference key and value pairs however, it is broken out into a
+                // "key_index" and an "complex_value". 
+                // 
+                // The "key_index" is much like the key index in the use for tags, but instead
+                // of pointing to "keys" field in the Layers, it points to the "string_values".
+                // This is the same value store as strings for use in values, so duplicates here
+                // will be pointing to the same indexed position. 
+                //
+                // An complex value has two parts, the first 4 bits are the type bits
+                // and the remaining bits are the parameter bits. What is stored in the parameter
+                // bits is dependant on what the type bit is selected. For example for inline values,
+                // the parameter field is not an index but simply a value. For other types it might
+                // be an index position into a value storage of the layer.
+                // 
+                // uint64t type = complex_value & 0x0F; // First 4 Bits
+                // uint64t parameter = complex_value >> 4;
+                // 
+                //     Type     | Id  | Parameter
+                // ---------------------------------
+                // inline sint  |  0  | value of integer ( values between -2^59+1 to 2^59-1 )
+                // inline uint  |  1  | value of unsigned integer ( values between 0 to 2^60-1 )
+                // bool/null    |  2  | value of 0 = false, 1 = true, 2 = null
+                // float        |  3  | index to float_values in layer
+                // double       |  4  | index to double_values in layer
+                // string       |  5  | index to string_values in layer
+                // int          |  6  | index to int_values in layer
+                // uint         |  7  | index to uint_values in layer
+                // list / map   |  8  | (if 4th bit is 0 is list)
+                //              |     |   remaining bits are length of the list where
+                //              |     |   each item in the list is a complex value
+                //              |     | (if 4th bit is 1 is map)
+                //              |     |   remaining bits are the number of key_index and 
+                //              |     |   complex_value pairs to follow (same as properties)
+                repeated uint64 properties = 5 [ packed = true ];
         }
 
         // Layers are described in section 4.1 of the specification
@@ -69,6 +109,12 @@ message Tile {
                 // See https://github.com/mapbox/vector-tile-spec/issues/47
                 optional uint32 extent = 5 [ default = 4096 ];
 
+                repeated string string_values = 7;
+                repeated double double_values = 8 [ packed = true ];
+                repeated float float_values = 9 [ packed = true ];
+                repeated sint64 sint64_values = 10 [ packed = true ];
+                repeated uint64 uint64_values = 11 [ packed = true ];
+
                 extensions 16 to max;
         }