From a64bf39d1fc4e6c27c431e673ac875ab56ac2450 Mon Sep 17 00:00:00 2001
From: SymbolixAU <dcooley@symbolix.com.au>
Date: Thu, 30 Aug 2018 12:20:59 +1000
Subject: [PATCH] empty points go to 0,0 - is this correct #32

---
 R/scratch.R    | 63 +++++++++++++++++++++++++++++++++++++++++++++++++-
 R/sfencoded.R  | 21 +++++++++++------
 src/encode.cpp | 16 +++++++------
 3 files changed, 85 insertions(+), 15 deletions(-)

diff --git a/R/scratch.R b/R/scratch.R
index 0e2c3e2e8..7ca1a1849 100644
--- a/R/scratch.R
+++ b/R/scratch.R
@@ -24,26 +24,87 @@
 # ept <- sf::st_sfc(sf::st_point())
 # pt <- sf::st_sfc(sf::st_point(c(1,1)))
 # 
+# sfept <- sf::st_sf(geometry = ept)
+# sfpt <- sf::st_sf(geometry = pt)
+# 
 # emp <- sf::st_sfc(sf::st_multipoint())
 # mp <- sf::st_sfc(sf::st_multipoint(matrix(1:4, ncol = 2)))
 # 
+# sfemp <- sf::st_sf(geometry = emp)
+# sfmp <- sf::st_sf(geometry = mp )
+# 
 # el <- sf::st_sfc(sf::st_linestring())
 # l <- sf::st_sfc(sf::st_linestring(matrix(1:4, ncol = 2)))
 # 
+# sfel <- sf::st_sf(geometry = el )
+# sfl <- sf::st_sf(geometry = l )
+# 
 # eml <- sf::st_sfc(sf::st_multilinestring())
 # ml <- sf::st_sfc(sf::st_multilinestring(x = list(matrix(1:4, ncol = 2))))
 # 
+# sfeml <- sf::st_sf(geometry = eml )
+# sfml <- sf::st_sf(geometry = ml )
+# 
 # epl <- sf::st_sfc(sf::st_polygon())
-# pl <- sf::st_sfc(sf::st_multipolygon(x = list(sf::st_polygon(list(x = matrix(c(0,0,1,0,1,1,0,1,0,0), ncol = 2, byrow = T))))))
+# pl <- sf::st_sfc(sf::st_polygon(list(x = matrix(c(0,0,1,0,1,1,0,1,0,0), ncol = 2, byrow = T))))
+# 
+# sfepl <- sf::st_sf(geometry = epl)
+# sfpl <- sf::st_sf(geometry = pl)
+# 
+# empl <- sf::st_sfc(sf::st_multipolygon())
+# mpl <- sf::st_sfc(sf::st_multipolygon(x = list(sf::st_polygon(list(x = matrix(c(0,0,1,0,1,1,0,1,0,0), ncol = 2, byrow = T))))))
+# 
+# sfempl <- sf::st_sf(geometry = empl)
+# sfmpl <- sf::st_sf(geometry = mpl)
+# 
+# 
 # 
 # encode(ept)
 # encode(pt)
+# 
+# encode(sfept)
+# encode(sfpt)
+# 
 # encode(emp)
 # encode(mp)
+# 
+# encode( sfemp )
+# encode( sfmp )
+# 
 # encode(el)
 # encode(l)
+# 
+# encode( sfel )
+# encode( sfl )
+# 
 # encode(eml)
 # encode(ml)
+# 
+# encode( sfeml )
+# encode( sfml )
+# 
 # encode(epl)
 # encode(pl)
 # 
+# encode( sfepl )
+# encode( sfpl )
+# 
+# encode(empl)
+# encode(mpl)
+# 
+# encode( sfempl )
+# encode( sfmpl )
+# 
+# 
+# library(googleway)
+# set_key(read.dcf("~/Documents/.googleAPI", fields = "GOOGLE_MAP_KEY"))
+# 
+# google_map() %>%
+#   add_markers(sfemp)
+# 
+# google_map() %>%
+#   add_polylines(data = sfel)
+# 
+# google_map() %>%
+#   add_polylines(data = sfeml)
+# 
diff --git a/R/sfencoded.R b/R/sfencoded.R
index f2bafbd91..898d6e45f 100644
--- a/R/sfencoded.R
+++ b/R/sfencoded.R
@@ -170,17 +170,24 @@ printSfEncodedPrefix <- function(e, encType) {
   
   if(encType == "sfencoded") {
     e <- vapply(e, function(z) {
-      paste0(
-        attr(z, "sfc")[2], ": ",
-        substr(z[1], 1, pmin(nchar(z[1]), 20)),
-        "..."
+      m <- pmin(nchar(z[1]), 20)
+      a <- attr(z, "sfc")[2]
+      ifelse(is.na(m), paste0(a, ": EMPTY"), 
+        paste0(
+          a, ": ",
+             substr(z[1], 1, m) 
+          , ifelse(m >= 20, "...", "")
+        )
       )
     }, "" )
   } else {
     e <- vapply(e, function(z) {
-      paste0(
-        substr(z[1], 1, pmin(nchar(z[1]), 20)),
-        "..."
+      m <- pmin(nchar(z[1]), 20)
+      ifelse(is.na(m), "EMPTY", 
+        paste0(
+          substr(z[1], 1, m),
+          ifelse(m >= 20, "...", "")
+        )
       )
     }, "" )
   }
diff --git a/src/encode.cpp b/src/encode.cpp
index 08047b619..0948f4589 100644
--- a/src/encode.cpp
+++ b/src/encode.cpp
@@ -298,15 +298,14 @@ void write_data(std::ostringstream& os, std::ostringstream& oszm, Rcpp::Characte
 Rcpp::List rcpp_encodeSfGeometry(Rcpp::List sfc, bool strip){
   
   Rcpp::CharacterVector cls_attr = sfc.attr("class");
-  
-  int db = 0;
-  
+
   Rcpp::CharacterVector sfg_dim;
   int dim_divisor;
   
   Rcpp::List output(sfc.size());
   Rcpp::List output_zm(sfc.size());
   int lastItem;
+  Rcpp::List thisSfc;
   
   // TODO(empty geometries should not enter this list and return something?)
   
@@ -317,11 +316,14 @@ Rcpp::List rcpp_encodeSfGeometry(Rcpp::List sfc, bool strip){
     Rcpp::checkUserInterrupt();
 
     sfg_dim = getSfClass(sfc[i]);
-
-    make_dim_divisor(sfg_dim[0], &dim_divisor);
+    thisSfc = sfc[i];
+    
+    if (thisSfc.size() > 0 ) {
       
-    write_data(os, oszm, sfg_dim, dim_divisor, sfc[i], cls_attr[0], 0);
-
+      make_dim_divisor(sfg_dim[0], &dim_divisor);
+      
+      write_data(os, oszm, sfg_dim, dim_divisor, sfc[i], cls_attr[0], 0);
+    }
 
     std::string str = os.str();
     // std::string zmstr = oszm.str();