diff --git a/src/editor/src/texture3d/image3d.cpp b/src/editor/src/texture3d/image3d.cpp
index db763051..9df8d815 100644
--- a/src/editor/src/texture3d/image3d.cpp
+++ b/src/editor/src/texture3d/image3d.cpp
@@ -291,7 +291,11 @@ void Image3DWidget::browse_filename()
                 if(new_filename.isEmpty())
                     return;
 
-                std::ifstream fin(new_filename.toStdString(), std::ios::in);
+                std::ifstream fin(new_filename.toStdString());
+                if(!fin)
+                    throw tracer::ObjectConstructionException(
+                        "failed to open file: " + new_filename.toStdString());
+
                 new_real_data = tracer::toRC(
                     tracer::texture3d_load::load_real_from_ascii(fin));
 
diff --git a/src/tracer/src/core/material/disney.cpp b/src/tracer/src/core/material/disney.cpp
index 2961d631..65c57d43 100644
--- a/src/tracer/src/core/material/disney.cpp
+++ b/src/tracer/src/core/material/disney.cpp
@@ -603,7 +603,7 @@ namespace disney_impl
             {
                 if(sam_selector < sample_w.transmission)
                     lwi = sample_transmission(lwo, new_sam);
-                else if(sam_selector -= sample_w.specular;
+                else if(sam_selector -= sample_w.transmission;
                         sam_selector < sample_w.specular)
                     lwi = sample_specular(lwo, new_sam);
                 else
diff --git a/src/tracer/src/core/material/dream_works_fabric.cpp b/src/tracer/src/core/material/dream_works_fabric.cpp
index 5fb90d1f..1a0acbb1 100644
--- a/src/tracer/src/core/material/dream_works_fabric.cpp
+++ b/src/tracer/src/core/material/dream_works_fabric.cpp
@@ -91,7 +91,7 @@ namespace
                 return {};
 
             const FVec3 lwh = (lwi + lwo).normalize();
-            const real S = std::pow(1 - std::abs(lwh.x), n_);
+            const real S = std::pow(1 - std::abs(lwh.x), static_cast<real>(n_));
 
             return color_ * S / Io[n_];
         }
@@ -139,7 +139,8 @@ namespace
 
             // construct result
 
-            const real S = std::pow(1 - std::abs(sin_theta_h), n_);
+            const real S = std::pow(
+                1 - std::abs(sin_theta_h), static_cast<real>(n_));
 
             SampleResult ret;
             ret.f   = color_ * S / Io[n_];
@@ -157,7 +158,8 @@ namespace
             const FVec3 lwh = (lwi + lwo).normalize();
             const real sin_theta_h = lwh.x;
 
-            const real S = std::pow(1 - std::abs(sin_theta_h), n_);
+            const real S = std::pow(
+                1 - std::abs(sin_theta_h), static_cast<real>(n_));
 
             return real(n_ + 1) * S / (8 * PI_r * dot(lwi, lwh));
         }
diff --git a/src/tracer/src/core/material/utility/microfacet.h b/src/tracer/src/core/material/utility/microfacet.h
index ad1fe834..f5074f84 100644
--- a/src/tracer/src/core/material/utility/microfacet.h
+++ b/src/tracer/src/core/material/utility/microfacet.h
@@ -10,7 +10,7 @@ namespace microfacet
     inline real one_minus_5(real x) noexcept
     {
         real t = 1 - x, t2 = t * t; return t2 * t2 * t;
-        }
+    }
 
     real gtr2(real cos_theta_h, real alpha) noexcept;