Add tests and documentation for 'interpolate_linestring'

README.rst

@@ -189,6 +189,33 @@ you would use::
 
 	var_dump(fraction_along_gc_line($point1, $point2, 0.25));
 
+Interpolating a GeoJSONLineString
+---------------------------------
+
+The ``interpolate_linestring`` functions takes a GeoJSONLineString. If the
+Pythagorean distance in degrees between two points in the line than the
+``epsilon`` value, it inserts a new point every ``epsilon / distance``
+fraction of the Great Circle Line.
+
+Given the Linestring::
+
+	$lineString = [
+		'type' => 'Linestring',
+		'coordinates' => [
+			[  5,  10 ],
+			[ 15,  10 ],
+			[  0, -50 ],
+		]
+	];
+
+The following will return an array with 26 elements::
+
+	var_dump(interpolate_linestring($lineString, 3));
+
+Five for the first pair, at fractions ``0.0``, ``0.3``, ``0.6``, ``0.9`` and
+``1.0``, and then two times, each another ``0.0485`` fraction along the Great
+Circle Line for the second pair.
+
 Geohashing
 ----------
 

php_geospatial.stub.php

@@ -38,11 +38,11 @@ function haversine(array $from, array $to, float $radius = GEO_EARTH_RADIUS): fl
 function vincenty(array $from, array $to, float $reference_ellipsoid = GEO_WGS84): float {}
 
 function fraction_along_gc_line(array $from, array $to, float $fraction): array {}
+function interpolate_linestring(array $line, float $epsilon): array {}
+
 function initial_bearing(array $from, array $to): float {}
 
 function rdp_simplify(array $points, float $epsilon): array {}
 
-function interpolate_linestring(array $line, float $epsilon): array {}
-
 function geohash_encode(array $point, int $precision = 12): string {}
 function geohash_decode(string $geohash): array {}

php_geospatial_arginfo.h

@@ -1,5 +1,5 @@
 /* This is a generated file, edit the .stub.php file instead.
- * Stub hash: 52022e47a6841ea20db60c2c92eba319cfc6c563 */
+ * Stub hash: 0fadd3390095e7624d9586206523e5352d345729 */
 
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_dms_to_decimal, 0, 3, IS_DOUBLE, 0)
 	ZEND_ARG_TYPE_INFO(0, degrees, IS_DOUBLE, 0)
@@ -58,6 +58,11 @@ ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_fraction_along_gc_line, 0, 3, IS
 	ZEND_ARG_TYPE_INFO(0, fraction, IS_DOUBLE, 0)
 ZEND_END_ARG_INFO()
 
+ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_interpolate_linestring, 0, 2, IS_ARRAY, 0)
+	ZEND_ARG_TYPE_INFO(0, line, IS_ARRAY, 0)
+	ZEND_ARG_TYPE_INFO(0, epsilon, IS_DOUBLE, 0)
+ZEND_END_ARG_INFO()
+
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_initial_bearing, 0, 2, IS_DOUBLE, 0)
 	ZEND_ARG_TYPE_INFO(0, from, IS_ARRAY, 0)
 	ZEND_ARG_TYPE_INFO(0, to, IS_ARRAY, 0)
@@ -68,11 +73,6 @@ ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_rdp_simplify, 0, 2, IS_ARRAY, 0)
 	ZEND_ARG_TYPE_INFO(0, epsilon, IS_DOUBLE, 0)
 ZEND_END_ARG_INFO()
 
-ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_interpolate_linestring, 0, 2, IS_ARRAY, 0)
-	ZEND_ARG_TYPE_INFO(0, line, IS_ARRAY, 0)
-	ZEND_ARG_TYPE_INFO(0, epsilon, IS_DOUBLE, 0)
-ZEND_END_ARG_INFO()
-
 ZEND_BEGIN_ARG_WITH_RETURN_TYPE_INFO_EX(arginfo_geohash_encode, 0, 1, IS_STRING, 0)
 	ZEND_ARG_TYPE_INFO(0, point, IS_ARRAY, 0)
 	ZEND_ARG_TYPE_INFO_WITH_DEFAULT_VALUE(0, precision, IS_LONG, 0, "12")
@@ -92,9 +92,9 @@ ZEND_FUNCTION(transform_datum);
 ZEND_FUNCTION(haversine);
 ZEND_FUNCTION(vincenty);
 ZEND_FUNCTION(fraction_along_gc_line);
+ZEND_FUNCTION(interpolate_linestring);
 ZEND_FUNCTION(initial_bearing);
 ZEND_FUNCTION(rdp_simplify);
-ZEND_FUNCTION(interpolate_linestring);
 ZEND_FUNCTION(geohash_encode);
 ZEND_FUNCTION(geohash_decode);
 
@@ -109,9 +109,9 @@ static const zend_function_entry ext_functions[] = {
 	ZEND_FE(haversine, arginfo_haversine)
 	ZEND_FE(vincenty, arginfo_vincenty)
 	ZEND_FE(fraction_along_gc_line, arginfo_fraction_along_gc_line)
+	ZEND_FE(interpolate_linestring, arginfo_interpolate_linestring)
 	ZEND_FE(initial_bearing, arginfo_initial_bearing)
 	ZEND_FE(rdp_simplify, arginfo_rdp_simplify)
-	ZEND_FE(interpolate_linestring, arginfo_interpolate_linestring)
 	ZEND_FE(geohash_encode, arginfo_geohash_encode)
 	ZEND_FE(geohash_decode, arginfo_geohash_decode)
 	ZEND_FE_END

tests/interpolate-line-string-001.phpt

@@ -0,0 +1,200 @@
+--TEST--
+Test for "interpolate_linestring" #1
+--FILE--
+<?php
+$lineString = [
+	'type' => 'Linestring',
+	'coordinates' => [
+		[  5,  10 ],
+		[ 15,  10 ],
+		[  0, -50 ],
+	]
+];
+
+var_dump(interpolate_linestring($lineString, 3));
+?>
+--EXPECTF--
+array(26) {
+  [0]=>
+  array(2) {
+    [0]=>
+    float(5)
+    [1]=>
+    float(10)
+  }
+  [1]=>
+  array(2) {
+    [0]=>
+    float(7.9998706635703245)
+    [1]=>
+    float(10.03143197167244)
+  }
+  [2]=>
+  array(2) {
+    [0]=>
+    float(11.000073920872426)
+    [1]=>
+    float(10.035925156338873)
+  }
+  [3]=>
+  array(2) {
+    [0]=>
+    float(14.000110773799255)
+    [1]=>
+    float(10.013466491669567)
+  }
+  [4]=>
+  array(2) {
+    [0]=>
+    float(14.999999999999998)
+    [1]=>
+    float(10)
+  }
+  [5]=>
+  array(2) {
+    [0]=>
+    float(14.431497984318062)
+    [1]=>
+    float(7.0743500242581225)
+  }
+  [6]=>
+  array(2) {
+    [0]=>
+    float(13.87016260996529)
+    [1]=>
+    float(4.148019326790382)
+  }
+  [7]=>
+  array(2) {
+    [0]=>
+    float(13.312974140472463)
+    [1]=>
+    float(1.221294808989993)
+  }
+  [8]=>
+  array(2) {
+    [0]=>
+    float(12.756998952507347)
+    [1]=>
+    float(-1.7055449208364544)
+  }
+  [9]=>
+  array(2) {
+    [0]=>
+    float(12.199328445763877)
+    [1]=>
+    float(-4.632223663590317)
+  }
+  [10]=>
+  array(2) {
+    [0]=>
+    float(11.63701903368877)
+    [1]=>
+    float(-7.55846185163128)
+  }
+  [11]=>
+  array(2) {
+    [0]=>
+    float(11.067030621797189)
+    [1]=>
+    float(-10.483970622513857)
+  }
+  [12]=>
+  array(2) {
+    [0]=>
+    float(10.486160869758637)
+    [1]=>
+    float(-13.408445478413974)
+  }
+  [13]=>
+  array(2) {
+    [0]=>
+    float(9.890972221197222)
+    [1]=>
+    float(-16.331559233911236)
+  }
+  [14]=>
+  array(2) {
+    [0]=>
+    float(9.277708136408956)
+    [1]=>
+    float(-19.252953899216553)
+  }
+  [15]=>
+  array(2) {
+    [0]=>
+    float(8.642194115015831)
+    [1]=>
+    float(-22.172231059691807)
+  }
+  [16]=>
+  array(2) {
+    [0]=>
+    float(7.979717846837639)
+    [1]=>
+    float(-25.08894018486976)
+  }
+  [17]=>
+  array(2) {
+    [0]=>
+    float(7.284881023816488)
+    [1]=>
+    float(-28.002564114424196)
+  }
+  [18]=>
+  array(2) {
+    [0]=>
+    float(6.55141274516024)
+    [1]=>
+    float(-30.91250069881375)
+  }
+  [19]=>
+  array(2) {
+    [0]=>
+    float(5.771930687062061)
+    [1]=>
+    float(-33.81803917851203)
+  }
+  [20]=>
+  array(2) {
+    [0]=>
+    float(4.937630724808758)
+    [1]=>
+    float(-36.718329304916004)
+  }
+  [21]=>
+  array(2) {
+    [0]=>
+    float(4.037877612215368)
+    [1]=>
+    float(-39.61234033808264)
+  }
+  [22]=>
+  array(2) {
+    [0]=>
+    float(3.059657259010722)
+    [1]=>
+    float(-42.49880573947054)
+  }
+  [23]=>
+  array(2) {
+    [0]=>
+    float(1.9868328958488306)
+    [1]=>
+    float(-45.37614734526896)
+  }
+  [24]=>
+  array(2) {
+    [0]=>
+    float(0.7991194226357126)
+    [1]=>
+    float(-48.2423696103279)
+  }
+  [25]=>
+  array(2) {
+    [0]=>
+    float(0)
+    [1]=>
+    float(-50)
+  }
+}

tests/interpolate-line-string-002.phpt

@@ -0,0 +1,59 @@
+--TEST--
+Test for "interpolate_linestring" #2
+--FILE--
+<?php
+$lineString = [
+	'type' => 'Linestring',
+	'coordinates' => [
+		[  0,   0 ],
+		[ 90,   0 ],
+	]
+];
+
+var_dump(interpolate_linestring($lineString, 20));
+?>
+--EXPECTF--
+array(6) {
+  [0]=>
+  array(2) {
+    [0]=>
+    float(0)
+    [1]=>
+    float(0)
+  }
+  [1]=>
+  array(2) {
+    [0]=>
+    float(19.999999999999996)
+    [1]=>
+    float(0)
+  }
+  [2]=>
+  array(2) {
+    [0]=>
+    float(40.00000000000001)
+    [1]=>
+    float(0)
+  }
+  [3]=>
+  array(2) {
+    [0]=>
+    float(59.99999999999999)
+    [1]=>
+    float(0)
+  }
+  [4]=>
+  array(2) {
+    [0]=>
+    float(80)
+    [1]=>
+    float(0)
+  }
+  [5]=>
+  array(2) {
+    [0]=>
+    float(90)
+    [1]=>
+    float(0)
+  }
+}