diff --git a/src/openrct2-ui/windows/Error.cpp b/src/openrct2-ui/windows/Error.cpp
index c8cdc1b62d..4a5e559cce 100644
--- a/src/openrct2-ui/windows/Error.cpp
+++ b/src/openrct2-ui/windows/Error.cpp
@@ -20,7 +20,7 @@
 #include <openrct2-ui/windows/Window.h>
 
 #include <openrct2/audio/audio.h>
-#include <openrct2/drawing/font.h>
+#include <openrct2/drawing/Font.h>
 #include <openrct2/interface/widget.h>
 #include <openrct2/localisation/localisation.h>
 
diff --git a/src/openrct2/drawing/font.c b/src/openrct2/drawing/Font.cpp
similarity index 98%
rename from src/openrct2/drawing/font.c
rename to src/openrct2/drawing/Font.cpp
index 7bc353a9c1..0c790876a5 100644
--- a/src/openrct2/drawing/font.c
+++ b/src/openrct2/drawing/Font.cpp
@@ -15,16 +15,20 @@
 #pragma endregion
 
 #include "../core/Guard.hpp"
+#include "../core/Util.hpp"
 #include "../localisation/localisation.h"
 #include "../sprites.h"
 #include "drawing.h"
-#include "font.h"
+#include "Font.h"
 #include "ttf.h"
 
 static const sint32 SpriteFontLineHeight[] = { 6, 10, 10, 18 };
 
 static uint8 _spriteFontCharacterWidths[896];
 
+extern "C"
+{
+
 #ifndef NO_TTF
 TTFFontSetDescriptor *gCurrentTTFFontSet;
 #endif // NO_TTF
@@ -125,7 +129,7 @@ sint32 font_sprite_get_codepoint_width(uint16 fontSpriteBase, sint32 codepoint)
     }
 
     sint32 spriteFontIdx = fontSpriteBase + font_sprite_get_codepoint_offset(codepoint);
-    if (spriteFontIdx < 0 || spriteFontIdx >= countof(_spriteFontCharacterWidths))
+    if (spriteFontIdx < 0 || spriteFontIdx >= (sint32)Util::CountOf(_spriteFontCharacterWidths))
     {
         log_warning("Invalid font index %u", spriteFontIdx);
         spriteFontIdx = 0;
@@ -270,3 +274,5 @@ bool font_supports_string(const utf8 *text, sint32 fontSize)
         return font_supports_string_sprite(text);
     }
 }
+
+}
diff --git a/src/openrct2/drawing/font.h b/src/openrct2/drawing/Font.h
similarity index 100%
rename from src/openrct2/drawing/font.h
rename to src/openrct2/drawing/Font.h
diff --git a/src/openrct2/drawing/drawing.h b/src/openrct2/drawing/drawing.h
index 7e902579c6..8f9a60bbeb 100644
--- a/src/openrct2/drawing/drawing.h
+++ b/src/openrct2/drawing/drawing.h
@@ -19,7 +19,7 @@
 
 #include "../common.h"
 #include "../interface/colour.h"
-#include "font.h"
+#include "Font.h"
 
 typedef struct rct_g1_element {
     uint8* offset;          // 0x00
diff --git a/src/openrct2/drawing/ttf.h b/src/openrct2/drawing/ttf.h
index 973bc60f92..8b06bc81c4 100644
--- a/src/openrct2/drawing/ttf.h
+++ b/src/openrct2/drawing/ttf.h
@@ -16,7 +16,7 @@
 
 #pragma once
 
-#include "font.h"
+#include "Font.h"
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/src/openrct2/interface/Fonts.h b/src/openrct2/interface/Fonts.h
index 02ca78c319..a1a30c6184 100644
--- a/src/openrct2/interface/Fonts.h
+++ b/src/openrct2/interface/Fonts.h
@@ -17,7 +17,7 @@
 #ifndef OPENRCT2_FONTS_H
 #define OPENRCT2_FONTS_H
 
-#include "../drawing/font.h"
+#include "../drawing/Font.h"
 
 #ifndef NO_TTF
 extern TTFFontSetDescriptor TTFFontMSGothic;
diff --git a/src/openrct2/localisation/language.h b/src/openrct2/localisation/language.h
index b869472536..9b6c0f7e6c 100644
--- a/src/openrct2/localisation/language.h
+++ b/src/openrct2/localisation/language.h
@@ -22,7 +22,7 @@
 #endif
 
 #include "../common.h"
-#include "../drawing/font.h"
+#include "../drawing/Font.h"
 
 enum {
     LANGUAGE_UNDEFINED,