diff --git a/agg/agg_color_rgba.h b/agg/agg_color_rgba.h
index b2a1b11..2e98b9d 100644
--- a/agg/agg_color_rgba.h
+++ b/agg/agg_color_rgba.h
@@ -438,7 +438,7 @@ namespace agg
             draw::ParseColor(_input, *this);
         };
         
-        uint32_t Get(void)
+        uint32_t Get(void) const
         {
             return ((uint32_t)r<<24)+((uint32_t)g<<16)+((uint32_t)b<<8)+((uint32_t)a);
         };
diff --git a/draw/Color.cpp b/draw/Color.cpp
index 1f6d504..954e47d 100644
--- a/draw/Color.cpp
+++ b/draw/Color.cpp
@@ -480,14 +480,14 @@ etk::CCout& agg::operator <<(etk::CCout &os, const  struct agg::rgba8& obj)
 }
 
 
-etk::UString draw::GetHexString(draw::Color& color)
+etk::UString draw::GetHexString(const draw::Color& color)
 {
 	char colorText[256];
 	sprintf(colorText, "0x%08X", color.Get());
 	return colorText;
 }
 
-etk::UString draw::GetString(draw::Color& color)
+etk::UString draw::GetString(const draw::Color& color)
 {
 	char colorText[256];
 	sprintf(colorText, "#%08X", color.Get());
diff --git a/draw/Color.h b/draw/Color.h
index 2919e89..5a60ae1 100644
--- a/draw/Color.h
+++ b/draw/Color.h
@@ -84,8 +84,8 @@ namespace draw {
 	};
 	
 	void ParseColor(const char* _input, struct agg::rgba8& color);
-	etk::UString GetHexString(draw::Color& color);
-	etk::UString GetString(draw::Color& color);
+	etk::UString GetHexString(const draw::Color& color);
+	etk::UString GetString(const draw::Color& color);
 	
 	namespace color {
 		extern const Color none;