diff --git a/src/celengine/galaxy.cpp b/src/celengine/galaxy.cpp
index a0103b891..ee2151825 100644
--- a/src/celengine/galaxy.cpp
+++ b/src/celengine/galaxy.cpp
@@ -112,20 +112,20 @@ constexpr const GalaxyTypeName GalaxyTypeNames[] =
     { "E7",  GalaxyType::E7 },
 };
 
-void galaxyTextureEval(float u, float v, float /*w*/, unsigned char *pixel)
+void galaxyTextureEval(float u, float v, float /*w*/, std::uint8_t *pixel)
 {
     float r = 0.9f - std::sqrt(u * u + v * v );
     if (r < 0)
         r = 0;
 
-    auto pixVal = static_cast<unsigned char>(r * 255.99f);
+    auto pixVal = static_cast<std::uint8_t>(r * 255.99f);
     pixel[0] = 255;//65;
     pixel[1] = 255;//64;
     pixel[2] = 255;//65;
     pixel[3] = pixVal;
 }
 
-void colorTextureEval(float u, float /*v*/, float /*w*/, unsigned char *pixel)
+void colorTextureEval(float u, float /*v*/, float /*w*/, std::uint8_t *pixel)
 {
     unsigned int i = static_cast<unsigned int>((static_cast<float>(u)*0.5f + 0.5f)*255.99f); // [-1, 1] -> [0, 255]
 
@@ -136,9 +136,9 @@ void colorTextureEval(float u, float /*v*/, float /*w*/, unsigned char *pixel)
     //convert Hue to RGB
     float r, g, b;
     DeepSkyObject::hsv2rgb(&r, &g, &b, hue, 0.20f, 1.0f);
-    pixel[0] = static_cast<unsigned char>(r * 255.99f);
-    pixel[1] = static_cast<unsigned char>(g * 255.99f);
-    pixel[2] = static_cast<unsigned char>(b * 255.99f);
+    pixel[0] = static_cast<std::uint8_t>(r * 255.99f);
+    pixel[1] = static_cast<std::uint8_t>(g * 255.99f);
+    pixel[2] = static_cast<std::uint8_t>(b * 255.99f);
 }
 
 struct GalaxyVertex
diff --git a/src/celengine/globular.cpp b/src/celengine/globular.cpp
index 9dc6ec735..943b365ab 100644
--- a/src/celengine/globular.cpp
+++ b/src/celengine/globular.cpp
@@ -80,7 +80,7 @@ constexpr const float RADIUS_CORRECTION = 0.025f;
 
 float CBin, RRatio, XI, Rr = 1.0f, Gg = 1.0f, Bb = 1.0f;
 
-void globularTextureEval(float u, float v, float /*w*/, unsigned char *pixel)
+void globularTextureEval(float u, float v, float /*w*/, std::uint8_t *pixel)
 {
     // use an exponential luminosity shape for the individual stars
     // giving sort of a halo for the brighter (i.e.bigger) stars.
@@ -91,7 +91,7 @@ void globularTextureEval(float u, float v, float /*w*/, unsigned char *pixel)
     if (lumi <= 0.0f)
         lumi = 0.0f;
 
-    auto pixVal = static_cast<unsigned char>(lumi * 255.99f);
+    auto pixVal = static_cast<std::uint8_t>(lumi * 255.99f);
     pixel[0] = 255;
     pixel[1] = 255;
     pixel[2] = 255;
@@ -123,7 +123,7 @@ float relStarDensity(float eta)
     return ((std::log(rho2) + 4.0f * (1.0f - std::sqrt(rho2)) * Xi) / (rho2 - 1.0f) + XI2) / (1.0f - 2.0f * Xi + XI2);
 }
 
-void centerCloudTexEval(float u, float v, float /*w*/, unsigned char *pixel)
+void centerCloudTexEval(float u, float v, float /*w*/, std::uint8_t *pixel)
 {
     /*! For reasons of speed, calculate central "cloud" texture only for
      *  8 bins of King_1962 concentration, c = CBin, XI(CBin), RRatio(CBin).
@@ -154,7 +154,7 @@ void centerCloudTexEval(float u, float v, float /*w*/, unsigned char *pixel)
     pixel[0] = 255;
     pixel[1] = 255;
     pixel[2] = 255;
-    pixel[3] = static_cast<unsigned char>(relStarDensity(eta) * profile_2d * 255.99f);
+    pixel[3] = static_cast<std::uint8_t>(relStarDensity(eta) * profile_2d * 255.99f);
 }
 
 void initGlobularData(celgl::VertexObject& vo,
diff --git a/src/celengine/texture.h b/src/celengine/texture.h
index 0b246333b..fb1d76c22 100644
--- a/src/celengine/texture.h
+++ b/src/celengine/texture.h
@@ -10,13 +10,14 @@
 #ifndef _CELENGINE_TEXTURE_H_
 #define _CELENGINE_TEXTURE_H_
 
+#include <cstdint>
 #include <string>
 #include <celutil/color.h>
 #include <celcompat/filesystem.h>
 #include <celengine/image.h>
 
 
-typedef void (*ProceduralTexEval)(float, float, float, unsigned char*);
+typedef void (*ProceduralTexEval)(float, float, float, std::uint8_t*);
 
 
 struct TextureTile
@@ -40,7 +41,7 @@ class TexelFunctionObject
     TexelFunctionObject() {};
     virtual ~TexelFunctionObject() {};
     virtual void operator()(float u, float v, float w,
-                            unsigned char* pixel) = 0;
+                            std::uint8_t* pixel) = 0;
 };