rework placment logic

tree.lua

+-- NUR DURCH 4 TEILBARE ZAHLEN > 20 VERWENDEN!!!
 local leds = {
-    32,
-    28,
-    16,
-    8,
-    4,
+    64,
+    56,
+    48,
+    36,
+    20,
 }
 
+for i = 1, #leds do
+    if leds[i] % 4 ~= 0 then
+        error("[ledtree] led count per layer must be divisible by 4. Error location: 'leds' table, item "..i..": "..leds[i])
+    end
+    if leds[i] < 20 then
+        error("[ledtree] led count per layer must be greater than or qual to 20. Error location: 'leds' table, item "..i..": "..leds[i])
+    end
+end
+
 local height_increment = 3
 
 local function breite(n)
@@ -28,13 +38,13 @@ local function place_layer(center, breite)
     breite = breite * 2 + 1
     local needles = {}
     local leds = {}
-    local max_offset = math.ceil(breite / 2)
-    for y = -height_increment / 2, height_increment / 2 do
+    local max_offset = math.floor(breite / 2)
+    for y = math.ceil(-height_increment / 2), math.floor(height_increment / 2) do
         for x = -max_offset, max_offset do
             for z = -max_offset, max_offset do
                 local pos = vector.new({x = center.x + x, y = center.y + y, z = center.z + z})
                 table.insert(needles, pos)
-                if is_led(center, breite, pos) then
+                if y == 0 and is_led(center, breite, pos) then
                     table.insert(leds, pos)
                 end
             end