Initial building part definition

Add the notion of a building part. Both building footprints and building
parts share in some shape definitions. These are pulled out in a common
defs.yaml file which are shared by buildings (footprints) and parts.

Validated/tested with the test.sh script

examples/buildings/building-part-basic.yaml

@@ -0,0 +1,33 @@
+---
+id: overture:buildings:part:1234
+type: Feature
+geometry:
+  type: Polygon
+  coordinates: [[
+            [-77.036873, 38.897804],
+            [-77.036873, 38.897559],
+            [-77.036260, 38.897559],
+            [-77.036260, 38.897804],
+            [-77.036873, 38.897804]
+          ]]
+properties:
+  # Custom user properties.
+  extFoo: I am a customer user property.
+  extBar: Me too!
+  # Overture properties
+  theme: buildings
+  type: part
+  version: 1
+  level: 1
+  updateTime: "2023-06-06T10:30:00-08:00"
+  height: 21.34
+  numFloors: 4
+  minHeight: 15.0
+  roofShape: dome
+  roofOrientation: across
+  roofDirection: 23.4
+  sources:
+  - property: ""
+    dataset: microsoftMLBuildings
+  - property: /properties/height
+    dataset:  metaLidarExtractions

schema/buildings/building.yaml

@@ -19,16 +19,9 @@ properties:
     allOf:
       - "$ref": ../defs.yaml#/$defs/propertyContainers/overtureFeaturePropertiesContainer
       - "$ref": ../defs.yaml#/$defs/propertyContainers/levelContainer
+      - "$ref": ./defs.yaml#/shapeContainer
     properties:
       names: { "$ref": "../defs.yaml#/$defs/propertyDefinitions/names" }
-      height:
-        description: Height of the building in meters
-        type: number
-        exclusiveMinimum: 0
-      numFloors:
-        description: Number of above-ground floors of the building
-        type: integer
-        exclusiveMinimum: 0
       class:
         description: >-
           A broad category of the building type / purpose. When the current use of the building does not match the built purpose, the class should
@@ -48,3 +41,6 @@ properties:
           - medical
           - entertainment
           - military
+      hasParts:
+        description: Flag indicating whether the building has parts
+        type: boolean

schema/buildings/building_part.yaml

@@ -0,0 +1,26 @@
+---
+"$schema": https://json-schema.org/draft/2020-12/schema
+title: Building Footprint Schema
+description: >-
+  A single building part. Parts describe their shape and color and other properties. Each
+  building part must contain the building with which it is associated.
+type: object
+properties:
+  geometry:
+    description: >-
+      The part's geometry. It must be a polygon or multipolygon.
+    unevaluatedProperties: false
+    oneOf:
+      - "$ref": https://geojson.org/schema/Polygon.json
+      - "$ref": https://geojson.org/schema/MultiPolygon.json
+  properties:
+    unevaluatedProperties: false
+    allOf:
+      - "$ref": ../defs.yaml#/$defs/propertyContainers/overtureFeaturePropertiesContainer
+      - "$ref": ../defs.yaml#/$defs/propertyContainers/levelContainer
+      - "$ref": ./defs.yaml#/shapeContainer
+    properties:
+      building:
+        description: The building ID that this part belongs to
+        type: string
+

schema/buildings/defs.yaml

@@ -0,0 +1,50 @@
+---
+"$schema": https://json-schema.org/draft/2020-12/schema
+title: Overture Maps Shared Building Properties
+description: Common schema definitions shared by building footprints and building parts
+shapeContainer:
+  properties:
+    height:
+      description: Height of the building in meters
+      type: number
+      exclusiveMinimum: 0
+    numFloors:
+      description: Number of above-ground floors of the building
+      type: integer
+      exclusiveMinimum: 0
+    minHeight:
+      description: The height of the bottom part of building in Height Units.  Used if a building or part of building starts above the ground leve
+      type: number
+    roofShape:
+      description: The shape of the roof
+      type: string
+      enum:
+        - dome
+        - flat
+        - gable
+        - gambrel
+        - half-hip
+        - hip
+        - mansard
+        - onion
+        - pyramid
+        - round
+        - spherical
+        - other
+    roofDirection:
+      description: Direction of the roof shape.
+      type: number
+      exclusiveMinimum: 0
+      exclusiveMaximum: 360
+    roofOrientation:
+      description: The shape of the roof
+      type: string
+      enum:
+        - across
+        - along
+    roofColor:
+      description: The color (name or color triplet) of the roof of a building or building part in hexadecimal 
+      type: string
+    eaveHeight:
+      description: The height of the building eave in Height Units
+      type: number

schema/defs.yaml

@@ -19,6 +19,7 @@ description: Common schema definitions shared by all themes
       enum:
         - connector
         - building
+        - part
         - segment
         - locality
         - administrativeBoundary

schema/schema.yaml

@@ -34,6 +34,14 @@ oneOf:
             type: { enum: [building] }
     then: { "$ref": buildings/building.yaml }
     else: { propertyNames: false }
+  - if:
+      properties:
+        properties:
+          properties:
+            theme: { enum: [buildings] }
+            type: { enum: [part] }
+    then: { "$ref": buildings/building_part.yaml }
+    else: { propertyNames: false }
   - if:
       properties:
         properties: