diff --git a/tiny-doc/src/docs/asciidoc/sandbox.adoc b/tiny-doc/src/docs/asciidoc/sandbox.adoc
index b9ddf345..5fedb347 100644
--- a/tiny-doc/src/docs/asciidoc/sandbox.adoc
+++ b/tiny-doc/src/docs/asciidoc/sandbox.adoc
@@ -38,3 +38,4 @@ end
 - https://minigdx.github.io/tiny/sandbox.html?game=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[AABB Collision]
 - https://minigdx.github.io/tiny/sandbox.html?game=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[Control sprite move]
 - https://minigdx.github.io/tiny/sandbox.html?game=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[Bouncing Bat]
+- https://minigdx.github.io/tiny/sandbox.html?game=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[Perlin and dither]
diff --git a/tiny-engine/src/commonMain/kotlin/com/github/minigdx/tiny/lua/MathExamples.kt b/tiny-engine/src/commonMain/kotlin/com/github/minigdx/tiny/lua/MathExamples.kt
new file mode 100644
index 00000000..67d67b78
--- /dev/null
+++ b/tiny-engine/src/commonMain/kotlin/com/github/minigdx/tiny/lua/MathExamples.kt
@@ -0,0 +1,46 @@
+package com.github.minigdx.tiny.lua
+
+//language=Lua
+const val MATH_PERLIN_EXAMPLE = """
+function _draw()
+    gfx.cls(8)
+
+    gfx.dither(0x0001)
+    local x = math.perlin(0.1, 0.2, tiny.frame / 100)
+    local y = math.perlin(0.4, 0.5, tiny.frame / 100)
+    shape.circlef(x * 256, y * 256, 64, 7)
+end
+"""
+
+//language=Lua
+const val MATH_RND_EXAMPLE = """
+local value = {}
+function _update()
+    table.insert(value, math.rnd(126))
+
+    if(#value > 50) then
+        table.remove(value, #value)
+    end
+end
+
+function _draw()
+    gfx.cls()
+    local y = 0
+    for v in all(value) do
+        print("rnd: "..v, 4, y)
+        y = y + 6
+    end
+end
+"""
+
+//language=Lua
+const val MATH_SIGN_EXAMPLE = """
+function _draw()
+    gfx.cls()
+    local cos = math.cos(tiny.t)
+    print("cos: "..cos)
+    print("sign: "..math.sign(cos), 0, 8)
+
+    shape.line(128, 128, 128 + cos * 128, 128, 9)
+end
+"""
diff --git a/tiny-engine/src/commonMain/kotlin/com/github/minigdx/tiny/lua/MathLib.kt b/tiny-engine/src/commonMain/kotlin/com/github/minigdx/tiny/lua/MathLib.kt
index b446f181..342fc712 100644
--- a/tiny-engine/src/commonMain/kotlin/com/github/minigdx/tiny/lua/MathLib.kt
+++ b/tiny-engine/src/commonMain/kotlin/com/github/minigdx/tiny/lua/MathLib.kt
@@ -36,7 +36,7 @@ class MathLib : org.luaj.vm2.lib.MathLib() {
         return math
     }
 
-    @TinyFunction("Return the sign of the number: -1 if negative. 1 otherwise.")
+    @TinyFunction("Return the sign of the number: -1 if negative. 1 otherwise.", example = MATH_SIGN_EXAMPLE)
     internal inner class sign : OneArgFunction() {
 
         @TinyCall("Return the sign of the number.")
@@ -112,7 +112,7 @@ class MathLib : org.luaj.vm2.lib.MathLib() {
         }
     }
 
-    @TinyFunction("Generate random values")
+    @TinyFunction("Generate random values", example = MATH_RND_EXAMPLE)
     internal inner class rnd : TwoArgFunction() {
         @TinyCall("Generate a random int (negative or positive value)")
         override fun call(): LuaValue {
@@ -172,7 +172,7 @@ class MathLib : org.luaj.vm2.lib.MathLib() {
         }
     }
 
-    @TinyFunction("Perlin noise. The random generated value is between 0 and 1.")
+    @TinyFunction("Perlin noise. The random generated value is between 0.0 and 1.0.", example = MATH_PERLIN_EXAMPLE)
     inner class perlin(seed: Long) : ThreeArgFunction() {
 
         private val permutation: MutableList<Int>
@@ -240,9 +240,9 @@ class MathLib : org.luaj.vm2.lib.MathLib() {
 
         @TinyCall("Generate a random value regarding the parameters x,y and z.")
         override fun call(
-            @TinyArg("x") arg1: LuaValue,
-            @TinyArg("y") arg2: LuaValue,
-            @TinyArg("z") arg3: LuaValue,
+            @TinyArg("x", description = "A value between 0.0 and 1.0.") arg1: LuaValue,
+            @TinyArg("y", description = "A value between 0.0 and 1.0.") arg2: LuaValue,
+            @TinyArg("z", description = "A value between 0.0 and 1.0.") arg3: LuaValue,
         ): LuaValue {
             return valueOf(noise(arg1.todouble(), arg2.todouble(), arg3.todouble()))
         }