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+# Supported resource types/drivers
+
+Mapproxy supports following resource types:
+ * tms: *tile map service* (bound layer)
+ * surface: surfaces (i.e. tileset generator)
+ * geodata: vector free layers
+
+Mapproxy provides multiple drivers (*generators*) for each resource type.
+
+## Basic resource layout
+
+NB: In following, all resource definitions are documented by pseudo format. Actual configuration is either
+a JSON file on disk (for JSON resource backend) or a python data tree. 
+ 
+ * `{}`: JSON object/python dictionary
+ * `[]` JSON/python array
+ * `String`: string data type
+ * `Int`: integral JSON number/python integer
+ * `Double`: real JSON number/python double
+ * `Boolean`: boolean JSON/python value
+ * `Array<type>`: array of given type(s)
+ * `Optional` given entry is optional
+ * `?` no fixed name
+
+Basic resource layout:
+
+resource = {
+    String comment      // any comment, ignored
+    String group        // group this resource belongs to
+    String id           // resource identifier (withing group)
+    String type         // data type (tms, surface, geodata)
+    String driver       // data generator (see below)
+    Object registry     // additional local resource registry, see below
+    Array<String, Int> credits // list of credits identifiers (either textual or numeric)
+    Object referenceFrames = { // range definitions for different reference frames
+        Object ? = { // reference frame ID, for example melown2015
+            lodRange: [ Int, Int ]               // LOD range this resource produces data
+            tileRange: [[Int, Int], [Int, Int]]  // tile range: minx, miny, maxx, maxy; inclusive range
+        }
+    }
+    Object definition = {...} // driver-dependent definition, see below
+}
+
+## TMS drivers
+
+### tms-raster
+
+Raster-based bound layer generator. Uses any raster GDAL dataset as its data source. Supports optional data masking.
+
+```javascript
+definition = {
+    String dataset         // path to GDAL dataset
+    Optional String mask   // path to RF mask or masking GDAL dataset
+    Optional String format // output image format, "jpg" or "png" (defaults to "jpg")
+    Optional Boolean transparent // Boundlayer is transparent, forces format to "png"
+}
+```