fixed compilation errors.

Author: drobnyjt

src/material.rs

@@ -332,7 +332,7 @@ pub fn surface_binding_energy<T: Geometry>(particle_1: &mut particle::Particle,
                 SurfaceBindingModel::PLANAR{..} => {
                     particle::surface_refraction(particle_1, Vector::new(dx/mag, dy/mag, dz/mag), Es);
                 }
-                _ => particle.E += Es;
+                _ => particle_1.E += Es,
             }
         }
     }
@@ -358,7 +358,7 @@ pub fn surface_binding_energy<T: Geometry>(particle_1: &mut particle::Particle,
                     SurfaceBindingModel::PLANAR{..} => {
                         particle::surface_refraction(particle_1, Vector::new(-dx/mag, -dy/mag, -dz/mag), -Es);
                     }
-                    _ => particle.E += -Es;
+                    _ => particle_1.E += -Es,
                 }
 
             } else {

src/particle.rs

@@ -210,8 +210,9 @@ pub fn particle_advance(particle_1: &mut particle::Particle, mfp: f64, asymptoti
 
 pub fn surface_refraction(particle: &mut Particle, normal: Vector, Es: f64) {
     let E = particle.E;
-    let costheta = particle.dir.dot(&normal);
 
+    let costheta = particle.dir.dot(&normal);
+
     let a = (E/(E + Es)).sqrt();
     let b = -(E).sqrt()*costheta;
     let c = (E*costheta.powi(2) + Es).sqrt();