initial version of normalization built-in

probably broken for negative values

init.lua

@@ -0,0 +1,61 @@
+math.randomseed(os.time())
+
+local heightmap = require((...)\gsub("%.", "/") .. "/heightmap")
+
+local floor = math.floor
+
+local function min(t)
+    local r = t[0][0]
+    for i=0,#t do
+        for j=0,#t[0] do
+            if r > t[i][j] then r = t[i][j] end
+        end
+    end
+    return r
+end
+
+local function max(t)
+    local r = t[0][0]
+    for i=0,#t do
+        for j=0,#t[0] do
+            if r < t[i][j] then r = t[i][j] end
+        end
+    end
+    return r
+end
+
+local function create(width, height, f, rangeMin, rangeMax)
+    local map = heightmap.create(width, height, f)
+
+    local minimum = min(map)
+    local maximum = max(map)
+
+    --[[
+    -- if minimum is below zero, + everything till minimum is zero
+    if minimum < 0 then
+        for i=0,#map do
+            for j=0,#map[0] do
+                map[i][j] = map[i][j] - minimum
+            end
+        end
+    end
+    --]]
+
+    -- normalize range of values to desired range
+    for i=0,#map do
+        for j=0,#map[0] do
+            --floor(map[i][j] * NEW_MAX_VALUE / maximum)
+            map[i][j] = (map[i][j] - minimum) / (maximum - minimum)
+        end
+    end
+
+    map.min = min(map)
+    map.max = max(map)
+
+    return map
+end
+
+return {
+    create = create,
+    defaultf = heightmap.defaultf
+}