diff --git a/Cargo.lock b/Cargo.lock
index eabd7c5..27ba727 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4,7 +4,7 @@ version = "0.1.0"
 dependencies = [
  "ansi_term 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -19,14 +19,19 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "libc"
-version = "0.2.15"
+version = "0.2.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "rand"
-version = "0.3.14"
+version = "0.3.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.15 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.20 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[metadata]
+"checksum ansi_term 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "23ac7c30002a5accbf7e8987d0632fa6de155b7c3d39d0067317a391e00a2ef6"
+"checksum getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)" = "d9047cfbd08a437050b363d35ef160452c5fe8ea5187ae0a624708c91581d685"
+"checksum libc 0.2.20 (registry+https://github.com/rust-lang/crates.io-index)" = "684f330624d8c3784fb9558ca46c4ce488073a8d22450415c5eb4f4cfb0d11b5"
+"checksum rand 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "022e0636ec2519ddae48154b028864bdce4eaf7d35226ab8e65c611be97b189d"
diff --git a/src/main.rs b/src/main.rs
index 1052b9e..09d2068 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -100,6 +100,7 @@ fn main() {
     }
 }
 
+#[inline]
 fn rainbow(frec: f32, i: f32) -> (u8, u8, u8) {
     let red = (f32::sin(frec * i) * 127.0 + 128.0) as u8;
     let green = (f32::sin(frec * i + 2.0 * PI / 3.0) * 127.0 + 128.0) as u8;