diff --git a/.gitignore b/.gitignore
index 587bbcb..e958ea8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,7 +3,7 @@ node_modules/
 !/src/libs/sqljsfork/dist/
 .vscode/
 /cache*/
-/extract/
+/extract*/
 *.code-workspace
 .*
 *.sqlite3
diff --git a/generated/maprenderconfig.schema.json b/generated/maprenderconfig.schema.json
new file mode 100644
index 0000000..f8da683
--- /dev/null
+++ b/generated/maprenderconfig.schema.json
@@ -0,0 +1,100 @@
+{
+	"properties": {
+		"layers": {
+			"items": {
+				"properties": {
+					"mode": {
+						"type": "string",
+						"enum": [
+							"3d",
+							"map",
+							"height",
+							"collision",
+							"locs",
+							"maplabels",
+							"rendermeta",
+							"minimap"
+						]
+					},
+					"name": {
+						"type": "string"
+					},
+					"pxpersquare": {
+						"type": "number"
+					},
+					"level": {
+						"type": "number"
+					},
+					"format": {
+						"type": "string",
+						"enum": [
+							"png",
+							"webp"
+						]
+					},
+					"usegzip": {
+						"type": "boolean"
+					},
+					"subtractlayers": {
+						"items": {
+							"type": "string"
+						}
+					},
+					"dxdy": {
+						"type": "number"
+					},
+					"dzdy": {
+						"type": "number"
+					},
+					"wallsonly": {
+						"type": "boolean"
+					}
+				},
+				"required": [
+					"mode",
+					"name",
+					"level",
+					"pxpersquare"
+				]
+			}
+		},
+		"tileimgsize": {
+			"type": "number"
+		},
+		"mapsizex": {
+			"type": "number"
+		},
+		"mapsizez": {
+			"type": "number"
+		},
+		"area": {
+			"default": "full",
+			"description": "A string representing the the map area to render. Either one of the named presets (main, full, test ...), or one or more chunk ranges. eg: 50.50,20.20-70.70",
+			"anyOf": [
+				{
+					"type": "string",
+					"pattern": "^\\d+\\.\\d+(-\\d+\\.\\d+)?(,\\d+\\.\\d+(-\\d+\\.\\d+)?)*$"
+				},
+				{
+					"type": "string",
+					"enum": [
+						"main",
+						"full",
+						"test"
+					]
+				},
+				{
+					"type": "string",
+					"pattern": "^\\w+$"
+				}
+			]
+		}
+	},
+	"required": [
+		"layers",
+		"tileimgsize",
+		"mapsizex",
+		"mapsizez",
+		"area"
+	]
+}
\ No newline at end of file
diff --git a/src/buildfiletypes.ts b/src/buildfiletypes.ts
index 5f725e0..c9f24eb 100644
--- a/src/buildfiletypes.ts
+++ b/src/buildfiletypes.ts
@@ -2,11 +2,13 @@ import * as fs from "fs";
 import * as path from "path";
 import * as opcode_reader from "./opcode_reader";
 import * as commentjson from "comment-json";
-
+import { maprenderConfigSchema } from "./jsonschemas";
 
 async function buildFileTypes() {
 	let basedir = path.resolve("./src/opcodes");
 	let outdir = path.resolve("./generated");
+
+	//generate config file metas
 	let files = fs.readdirSync(basedir);
 	if (files.some(f => !path.basename(f).match(/\.jsonc?$/))) {
 		console.error("non-json files matched, is path wrong?");
@@ -35,6 +37,8 @@ async function buildFileTypes() {
 		fs.writeFileSync(outfile, typesfile);
 	}
 
+	//other one off files
+	fs.writeFileSync(path.resolve(outdir, "maprenderconfig.schema.json"), JSON.stringify(maprenderConfigSchema, undefined, "\t"));
 }
 
 buildFileTypes();
\ No newline at end of file
diff --git a/src/jsonschemas.ts b/src/jsonschemas.ts
index 9efa95e..3d8e113 100644
--- a/src/jsonschemas.ts
+++ b/src/jsonschemas.ts
@@ -173,7 +173,15 @@ export const maprenderConfigSchema: JSONSchema6 = {
         tileimgsize: number,
         mapsizex: number,
         mapsizez: number,
-        area: string
+        area: {
+            default: "full",
+            description: "A string representing the the map area to render. Either one of the named presets (main, full, test ...), or one or more chunk ranges. eg: 50.50,20.20-70.70",
+            anyOf: [
+                { type: "string", pattern: /^\d+\.\d+(-\d+\.\d+)?(,\d+\.\d+(-\d+\.\d+)?)*$/.source },
+                { type: "string", enum: ["main", "full", "test"] },
+                { type: "string", pattern: /^\w+$/.source },
+            ]
+        }
     },
     required: ["layers", "tileimgsize", "mapsizex", "mapsizez", "area"]
 }
\ No newline at end of file
diff --git a/src/scripts/dependencies.ts b/src/scripts/dependencies.ts
index a299aaf..f8c304b 100644
--- a/src/scripts/dependencies.ts
+++ b/src/scripts/dependencies.ts
@@ -9,6 +9,8 @@ import { crc32, crc32addInt } from "../libs/crc32util";
 import { arrayEnum, trickleTasksTwoStep, trickleTasks } from "../utils";
 import { EngineCache, iterateConfigFiles } from "../3d/modeltothree";
 import { legacyMajors, legacyGroups } from "../cache/legacycache";
+import { mapsquare_overlays } from "../../generated/mapsquare_overlays";
+import { mapsquare_underlays } from "../../generated/mapsquare_underlays";
 
 const depids = arrayEnum(["material", "model", "item", "loc", "mapsquare", "sequence", "skeleton", "frameset", "animgroup", "npc", "framebase", "texture", "enum", "overlay", "underlay"]);
 const depidmap = Object.fromEntries(depids.map((q, i) => [q, i]));
@@ -51,7 +53,7 @@ function chunkDeps(data: ChunkData, addDep: DepCallback, addHash: HashCallback)
 	}
 	//set iterators are same as insertion order according to the spec
 	overlays.forEach(id => addDep("overlay", id, "mapsquare", squareindex));
-	underlays.forEach(id => addDep("overlay", id, "mapsquare", squareindex));
+	underlays.forEach(id => addDep("underlay", id, "mapsquare", squareindex));
 }
 
 const mapsquareDeps2: DepCollector = async (cache, addDep, addHash, args) => {
@@ -68,27 +70,41 @@ const mapsquareDeps2: DepCollector = async (cache, addDep, addHash, args) => {
 	});
 }
 
+function coltoint(col: number[] | undefined | null) {
+	if (!col) { return 0xff00ff; }
+	return col[0] << 16 | col[1] << 8 | col[2];
+}
+
+function hashFloorType(lay: mapsquare_overlays & mapsquare_underlays, hash: number) {
+	hash = crc32addInt(+!!lay.bleedToUnderlay, hash);
+	hash = crc32addInt(lay.bleedpriority ?? -1, hash);
+	hash = crc32addInt(lay.materialbyte ?? lay.material ?? -1, hash);
+	hash = crc32addInt(coltoint(lay.color), hash);
+	hash = crc32addInt(coltoint(lay.secondary_colour), hash);
+	hash = crc32addInt(coltoint(lay.tertiary_colour), hash);
+	hash = crc32addInt(lay.material_tiling ?? -1, hash);
+	return hash;
+}
+
 const mapUnderlayDeps: DepCollector = async (cache, addDep, addHash) => {
 	for (let [id, underlay] of cache.mapUnderlays.entries()) {
 		if (!underlay) { continue; }
-		//the original underlay file may not even exist in some versions, just rebuild one for the hash
-		//its actually an overlay config in legacy caches
-		let rebuiltfile = (cache.legacyData ? parse.mapsquareOverlays : parse.mapsquareUnderlays).write(underlay);
-		let crc = crc32(rebuiltfile);
+
+		let crc = hashFloorType(underlay, 0);
 		addHash("underlay", id, crc, 0);
 		if (underlay.material) {
 			addDep("material", underlay.material, "underlay", id);
 		}
 	}
 }
+
 const mapOverlayDeps: DepCollector = async (cache, addDep, addHash) => {
 	for (let [id, overlay] of cache.mapOverlays.entries()) {
 		if (!overlay) { continue; }
 		//the original overlay file may not even exist in some versions, just rebuild one for the hash
-		let rebuiltfile = parse.mapsquareOverlays.write(overlay);
-		let crc = crc32(rebuiltfile);
+		let crc = hashFloorType(overlay, 0);
 		if (overlay.material) {
-			addDep("material", overlay.material, "underlay", id);
+			addDep("material", overlay.material, "overlay", id);
 		}
 		addHash("overlay", id, crc, 0);
 	}