Added emscripten calls for hz interpretation

This also uncovered a weird compilation issue. Emscripten did NOT like
me using the remainder operator with a floating point number.

2 files changed, 7 insertions, 19 deletions

diff --git a/src/emscripten_api.rs b/src/emscripten_api.rs
index ec6704e..c371d86 100644
--- a/src/emscripten_api.rs
+++ b/src/emscripten_api.rs
@@ -1,5 +1,8 @@
 use transforms;
 
+use std::os::raw::c_char;
+use std::ffi::CString;
+
 #[no_mangle]
 pub extern "C" fn find_fundamental_frequency(signal: *const f32, signal_length: isize, sample_rate: f32) -> f32 {
     use std::slice;
@@ -11,29 +14,14 @@ pub extern "C" fn find_fundamental_frequency(signal: *const f32, signal_length:
 }
 
 #[no_mangle]
-pub extern "C" fn correlation(signal: *const f32, signal_length: isize) {
-    //TODO correlate inline
-}
-
-#[no_mangle]
 pub extern "C" fn hz_to_cents_error(hz: f32) -> f32 {
-    //TODO implement
-    0.0
+    transforms::hz_to_cents_error(hz)
 }
 
-use std::os::raw::c_char;
-use std::ffi::CStr;
-use std::ffi::CString;
-
 #[no_mangle]
 pub extern "C" fn hz_to_pitch(hz: f32) -> *mut c_char {
-    //TODO implement
-    CString::new("C 4")
+    let pitch = transforms::hz_to_pitch(hz);
+    CString::new(pitch)
 		.unwrap()
         .into_raw()
 }
-
-#[no_mangle]
-pub extern "C" fn align_to_rising_edge(signal: *const f32, signal_length: isize) {
-    //TODO format signal nicely inline
-}
diff --git a/src/transforms.rs b/src/transforms.rs
index 55f81b6..aaae83b 100644
--- a/src/transforms.rs
+++ b/src/transforms.rs
@@ -169,7 +169,7 @@ fn hz_to_midi_number(hz: f32) -> f32 {
 
 pub fn hz_to_cents_error(hz: f32) -> f32 {
     let midi_number = hz_to_midi_number(hz);
-    let cents = (midi_number % 1.0) * 100.0;
+    let cents = (midi_number - midi_number.floor()) * 100.0;
     if cents >= 50.0 {
         cents - 100.0
     }