Merge pull request #8 from TianyiShi2001/remove-clamp-macro

replace the clamp macro with the clamp function

src/lib.rs

@@ -59,20 +59,15 @@ that this copyright notice remain intact.
 //! let indixes: Vec<u8> = data.chunks(4).map(|pix| nq.index_of(pix) as u8).collect();
 //! let color_map = nq.color_map_rgba();
 //! ```
-//! 
+
+mod math;
+use crate::math::clamp;
+
 use std::cmp::{
     max,
     min
 };
 
-macro_rules! clamp(		
-    ($x:expr) => (match $x {		
-        x if x < 0 => 0,		
-        x if x > 255 => 255,		
-        x => x		
-    })		
-);
-
 const CHANNELS: usize = 4;
 
 const RADIUS_DEC: i32 = 30; // factor of 1/30 each cycle
@@ -337,10 +332,10 @@ impl NeuQuant {
     /// initializes the color map
     fn build_colormap(&mut self) {
         for i in 0usize..self.netsize {
-            self.colormap[i].b = clamp!(self.network[i].b.round() as i32);
-            self.colormap[i].g = clamp!(self.network[i].g.round() as i32);
-            self.colormap[i].r = clamp!(self.network[i].r.round() as i32);
-            self.colormap[i].a = clamp!(self.network[i].a.round() as i32);
+            self.colormap[i].b = clamp(self.network[i].b.round() as i32);
+            self.colormap[i].g = clamp(self.network[i].g.round() as i32);
+            self.colormap[i].r = clamp(self.network[i].r.round() as i32);
+            self.colormap[i].a = clamp(self.network[i].a.round() as i32);
         }
     }
 

src/math.rs

@@ -0,0 +1,11 @@
+#[inline]
+pub(crate) fn clamp(a: i32) -> i32
+{
+    if a < 0 {
+        0
+    } else if a > 255 {
+        255
+    } else {
+        a
+    }
+}