diff --git a/benchmarks/benchmark_opencascade/main.cpp b/benchmarks/benchmark_opencascade/main.cpp
index 6a0689f..cd9e44b 100644
--- a/benchmarks/benchmark_opencascade/main.cpp
+++ b/benchmarks/benchmark_opencascade/main.cpp
@@ -68,7 +68,7 @@ public:
     Standard_Boolean Show(const Standard_Boolean /*force*/) override
     {
         const Standard_Real pc = this->GetPosition(); // Always within [0,1]
-        const int val = 1 + pc * (100 - 1);
+        const int val = static_cast<int>(1 + pc * (100 - 1));
         if (val > m_val) {
             std::cout << val;
             if (val < 100)
diff --git a/src/gmio_amf/amf_document.h b/src/gmio_amf/amf_document.h
index fcfc024..fa41c59 100644
--- a/src/gmio_amf/amf_document.h
+++ b/src/gmio_amf/amf_document.h
@@ -44,16 +44,18 @@
 
 #include <stddef.h>
 
+/*! Addition information about an element(eg name, description, ... */
 struct gmio_amf_metadata {
     const char* type; /*!< UTF8-encoded */
     const char* data; /*!< UTF8-encoded */
 };
 
+/*! Red, green, blue and alpha channels as numbers or formulas in [0,1] */
 struct gmio_amf_color {
-    double r; /*!< Red channel in [0,1] */
-    double g; /*!< Green channel in [0,1] */
-    double b; /*!< Blue channel in [0,1] */
-    double a; /*!< Optional alpha(transparency) channel in [0,1] */
+    double r;
+    double g;
+    double b;
+    double a;
     const char* r_formula;
     const char* g_formula;
     const char* b_formula;
@@ -77,7 +79,7 @@ struct gmio_amf_composite {
     const char* value_formula;
 };
 
-/*! Vertex within an AMF mesh */
+/*! Vertex within a mesh */
 struct gmio_amf_vertex {
     struct gmio_vec3d coords;
     bool has_normal;
@@ -87,7 +89,7 @@ struct gmio_amf_vertex {
     uint32_t metadata_count;
 };
 
-/*! Edge within an AMF mesh, for curved triangles */
+/*! Edge within a mesh, for curved triangles */
 struct gmio_amf_edge {
     uint32_t v1; /* XML:nonNegativeInteger */
     uint32_t v2; /* XML:nonNegativeInteger */
@@ -122,7 +124,7 @@ enum gmio_amf_volume_type {
     GMIO_AMF_VOLUME_TYPE_SUPPORT
 };
 
-/*! Volume within an AMF mesh */
+/*! Closed volume of an object */
 struct gmio_amf_volume {
     uint32_t materialid; /* XML:nonNegativeInteger */
     enum gmio_amf_volume_type type;
@@ -132,12 +134,14 @@ struct gmio_amf_volume {
     struct gmio_amf_color color; /* XML:Color */
 };
 
+/*! Triangular mesh referencing a set of vertices */
 struct gmio_amf_mesh {
     uint32_t vertex_count;
     uint32_t edge_count;
     uint32_t volume_count;
 };
 
+/*! Volume or volumes of material */
 struct gmio_amf_object {
     uint32_t id; /* XML:integer */
     uint32_t mesh_count;
@@ -146,13 +150,14 @@ struct gmio_amf_object {
     struct gmio_amf_color color; /* XML:Color */
 };
 
+/*! Combination of objects */
 struct gmio_amf_constellation {
     uint32_t id; /* XML:integer */
     uint32_t instance_count; /*!< Should be >= 2 */
     uint32_t metadata_count;
 };
 
-/*! Instance within an AMF constellation */
+/*! Position of an object in a constellation */
 struct gmio_amf_instance
 {
     uint32_t objectid; /* XML:nonNegativeInteger */
diff --git a/src/gmio_amf/amf_io.h b/src/gmio_amf/amf_io.h
index 57b05ef..a957448 100644
--- a/src/gmio_amf/amf_io.h
+++ b/src/gmio_amf/amf_io.h
@@ -53,6 +53,10 @@ GMIO_C_LINKAGE_BEGIN
  *  buffer</i> and the second half is employed as a <i>compression buffer</i>
  *  for zlib.
  *
+ *  If specified, gmio_amf_write_options::task_iface::func_is_stop_requested
+ *  is checked each time the gmio_amf_write_options::stream_memblock is about
+ *  to be flushed to the stream.
+ *
  *  \pre <tt> stream != NULL </tt>
  *  \pre <tt> doc != NULL </tt>
  *
diff --git a/src/gmio_core/internal/itoa.h b/src/gmio_core/internal/itoa.h
index 0dd957c..37955a2 100644
--- a/src/gmio_core/internal/itoa.h
+++ b/src/gmio_core/internal/itoa.h
@@ -50,9 +50,7 @@ char* gmio_u32toa(uint32_t value, char* str)
         *str++ = '0' + (char)value;
         return str;
     }
-    else {
-        return u32toa_branchlut(value, str);
-    }
+    return u32toa_branchlut(value, str);
 }
 
 char* gmio_i32toa(int32_t value, char* str)