Starting 1.2 spec version

studentdsx · Oct 11, 2011 · b5b4024 · b5b4024
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diff --git a/1.2/spec.md b/1.2/spec.md
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+# MBTiles 1.1
+
+# Sub-sections:
+
+* **Interaction**: HTTP endpoints needed for implementing interactivity
+* **UTFGrid**: storage of data used for interactivity
+
+## Abstract
+
+MBTiles is a specification for storing tiled map data in
+[SQLite](http://sqlite.org/) databases for immediate usage and for transfer.
+MBTiles files, known as **tilesets**, must implement the specification below
+to ensure compatibility with devices.
+
+## Database Specifications
+
+Tilesets are expected to be valid SQLite databases of
+[version 3.0.0](http://sqlite.org/formatchng.html) or higher.
+Only core SQLite features are permitted; tilesets **cannot require extensions**.
+
+## Database
+
+Note: the schemas outlined are meant to be followed as interfaces.
+SQLite views that produce compatible results are equally valid.
+For convenience, this specification refers to tables and virtual
+tables (views) as tables.
+
+### Metadata
+
+#### Schema
+
+The database is required to contain a table or view named `metadata`.
+
+This table must yield exactly two columns named `name` and
+`value`. A typical create statement for the `metadata` table:
+
+    CREATE TABLE metadata (name text, value text);
+
+#### Content
+
+The metadata table is used as a key/value store for settings. Five keys are **required**:
+
+* `name`: The plain-english name of the tileset.
+* `type`: `overlay` or `baselayer`
+* `version`: The version of the tileset, as a plain number.
+* `description`: A description of the layer as plain text.
+* `format`: The image file format of the tile data: `png` or `jpg`
+
+One row in `metadata` is **suggested** and, if provided, may enhance performance.
+
+* `bounds`: The maximum extent of the rendered map area. Bounds must define an
+  area covered by all zoom levels. The bounds are represented in `WGS:84` -
+  latitude and longitude values, in the OpenLayers Bounds format -
+  **left, bottom, right, top**. Example of the full earth: `-180.0,-85,180,85`.
+
+Several additional keys are supported for tilesets that implement
+UTFGrid-based interaction. See `interaction.md`.
+
+### Tiles
+
+#### Schema
+
+The database is required to contain a table named `tiles`.
+
+The table must yield four columns named `zoom_level`, `tile_column`,
+`tile_row`, and `tile_data`. A typical create statement for the `tiles` table:
+
+    CREATE TABLE tiles (zoom_level integer, tile_column integer, tile_row integer, tile_data blob);
+
+#### Content
+
+The tiles table contains tiles and the values used to locate them.
+The `zoom_level`, `tile_column`, and `tile_row` columns follow the
+[Tile Map Service Specification](http://wiki.osgeo.org/wiki/Tile_Map_Service_Specification) in
+their construction, but in a restricted form:
+
+* **The [global-mercator](http://wiki.osgeo.org/wiki/Tile_Map_Service_Specification#global-mercator) (aka Spherical Mercator) profile is assumed**
+
+The `blob` column contains raw image data in binary.
+
+A subset of image file formats are permitted:
+
+* `png`
+* `jpg`
diff --git a/README.md b/README.md
@@ -7,6 +7,7 @@ to ensure compatibility with devices.
 
 # Versions
 
+* **Development** - NOT USABLE: [1.2](https://github.com/mapbox/mbtiles-spec/blob/master/1.2/spec.md)
 * **Stable**: [1.1](https://github.com/mapbox/mbtiles-spec/blob/master/1.1/spec.md)
 * [1.0](https://github.com/mapbox/mbtiles-spec/blob/master/1.0/spec.md)