From 4a5aebea43c4e8cf42a9965bad77501755574a51 Mon Sep 17 00:00:00 2001
From: Eric Fischer <enf@pobox.com>
Date: Wed, 31 Oct 2018 10:43:21 -0700
Subject: [PATCH] Change representation of null/true/false to match
 vector-tile-base

---
 mvt.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/mvt.cpp b/mvt.cpp
index e567a1a..85e2656 100644
--- a/mvt.cpp
+++ b/mvt.cpp
@@ -935,10 +935,10 @@ void mvt_layer::tag_v3_value(mvt_value value, std::vector<unsigned long> &onto)
 			}
 			onto.push_back(vo);
 		} else if (value.type == mvt_bool) {
-			vo = (value.numeric_value.bool_value << 4) | 7;
+			vo = ((value.numeric_value.bool_value + 1) << 4) | 7;
 			onto.push_back(vo);
 		} else if (value.type == mvt_null) {
-			vo = (2 << 4) | 7;
+			vo = (0 << 4) | 7;
 			onto.push_back(vo);
 		} else if (value.type == mvt_list) {
 			bool all_ints = true;
@@ -1137,12 +1137,12 @@ mvt_value mvt_layer::decode_property(std::vector<unsigned long> const &property,
 		return ret;
 
 	case 7: /* boolean */
-		if ((property[off] >> 4) == 2) {
+		if ((property[off] >> 4) == 0) {
 			ret.type = mvt_null;
 			ret.numeric_value.null_value = 0;
 		} else {
 			ret.type = mvt_bool;
-			ret.numeric_value.bool_value = property[off] >> 4;
+			ret.numeric_value.bool_value = (property[off] >> 4) - 1;
 		}
 		return ret;