From eb4293df40c04789016552a83e22bdda3271a5c2 Mon Sep 17 00:00:00 2001 From: marqh Date: Thu, 27 Dec 2018 11:50:02 +0000 Subject: [PATCH 1/4] use text string for wkt-crs --- spec.md | 30 +++--------------------------- 1 file changed, 3 insertions(+), 27 deletions(-) diff --git a/spec.md b/spec.md index 8f10fc6..974e259 100644 --- a/spec.md +++ b/spec.md @@ -408,35 +408,11 @@ Example of a vertical CRS, here representing height above the NAV88 datum: ``` #### 5.1.4 Providing inline definitions of CRSs -Sometimes there may be no well-known identifier for a geospatial CRS. Or the data provider may wish to make the CoverageJSON file more self-contained by avoiding external lookups. In this case a full inline definition of the CRS in JSON (instead of, or in addition to the `"id"`). This has not yet been fully defined in this specification, but we recommend following the OGC Well-Known Text (WKT) structure, for example: +Sometimes there may be no well-known identifier for a geospatial CRS. Or the data provider may wish to make the CoverageJSON file more self-contained by avoiding external lookups. In this case a full inline definition of the CRS in JSON (instead of, or in addition to the `"id"`) may be provided. -```json -{ - "type": "VerticalCRS", - "id": "http://www.opengis.net/def/crs/EPSG/0/5703", - "datum": { - "id": "http://www.opengis.net/def/datum/EPSG/0/5103", - "label": { - "en": "North American Vertical Datum 1988" - } - }, - "cs": { - "id": "http://www.opengis.net/def/cs/EPSG/0/6499", - "csAxes": [{ - "id": "http://www.opengis.net/def/axis/EPSG/0/114", - "name": { - "en": "Gravity-related height" - }, - "direction": "up", - "unit": { - "symbol": "m" - } - }] - } -} -``` +It is recommended that a Well-Known Text Coordinate Reference System String, conforming to the OGC WKT-CRS and ISO19162 joint specification is included as a string attribute. -In future work, a mapping from OGC WKT2 to JSON may be defined, and may be adopted into the CoverageJSON specification. +The attribute name shall be `"WKTCRS"`. ### 5.2. Temporal Reference Systems From ad42621ad0092962210ac5cf8f81813c58713cfd Mon Sep 17 00:00:00 2001 From: marqh Date: Thu, 27 Dec 2018 16:00:33 +0000 Subject: [PATCH 2/4] return vertical datum example as WKT string --- spec.md | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/spec.md b/spec.md index 974e259..17280c3 100644 --- a/spec.md +++ b/spec.md @@ -414,6 +414,16 @@ It is recommended that a Well-Known Text Coordinate Reference System String, con The attribute name shall be `"WKTCRS"`. +```json +{ + "WKTCRS": "VERTCRS["NAVD88 height", + VDATUM["North American Vertical Datum 1988"], + CS[vertical,1], + AXIS["gravity-related height (H)",up], + LENGTHUNIT["metre",1.0]]" +} +``` + ### 5.2. Temporal Reference Systems From c9f4e70f662270e379f43039a10fb0a65a93c97a Mon Sep 17 00:00:00 2001 From: marqh Date: Fri, 28 Dec 2018 11:08:45 +0000 Subject: [PATCH 3/4] escape characters for WKT --- spec.md | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/spec.md b/spec.md index 17280c3..968540d 100644 --- a/spec.md +++ b/spec.md @@ -414,17 +414,14 @@ It is recommended that a Well-Known Text Coordinate Reference System String, con The attribute name shall be `"WKTCRS"`. +The following example inlcudes escape characters for all of the double quote characters in the WKT-CRS, which are required. It also includes escaped line returns and extra whitespace; whilst these are not required for WKT-CRS they do aid readability. + ```json { - "WKTCRS": "VERTCRS["NAVD88 height", - VDATUM["North American Vertical Datum 1988"], - CS[vertical,1], - AXIS["gravity-related height (H)",up], - LENGTHUNIT["metre",1.0]]" + "WKTCRS": "VERTCRS[\"NAVD88 height\",\\n VDATUM[\"North American Vertical Datum 1988\"],\\n CS[vertical, 1],\\n AXIS[\"gravity-related height (H)\", up],\\n LENGTHUNIT[\"metre\", 1.0]]" } ``` - ### 5.2. Temporal Reference Systems Time is referenced by a temporal reference system (temporal RS). From f664bfb8a84dc822656025902edc0b01ce824db5 Mon Sep 17 00:00:00 2001 From: marqh Date: Fri, 28 Dec 2018 11:41:34 +0000 Subject: [PATCH 4/4] remove line returns --- spec.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/spec.md b/spec.md index 968540d..1ec9909 100644 --- a/spec.md +++ b/spec.md @@ -414,11 +414,11 @@ It is recommended that a Well-Known Text Coordinate Reference System String, con The attribute name shall be `"WKTCRS"`. -The following example inlcudes escape characters for all of the double quote characters in the WKT-CRS, which are required. It also includes escaped line returns and extra whitespace; whilst these are not required for WKT-CRS they do aid readability. +The following example inlcudes escape characters for all of the double quote characters in the WKT-CRS, which are required. ```json { - "WKTCRS": "VERTCRS[\"NAVD88 height\",\\n VDATUM[\"North American Vertical Datum 1988\"],\\n CS[vertical, 1],\\n AXIS[\"gravity-related height (H)\", up],\\n LENGTHUNIT[\"metre\", 1.0]]" + "WKTCRS": "VERTCRS[\"NAVD88 height\",VDATUM[\"North American Vertical Datum 1988\"],CS[vertical, 1],AXIS[\"gravity-related height (H)\", up],LENGTHUNIT[\"metre\", 1.0]]" } ```