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diff --git a/data/map_02.png b/data/map_02.png
new file mode 100644
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diff --git a/data/map_03.png b/data/map_03.png
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diff --git a/tests/stb.dsp b/tests/stb.dsp
index 68c1806..b5ce917 100644
--- a/tests/stb.dsp
+++ b/tests/stb.dsp
@@ -66,7 +66,7 @@ LINK32=link.exe
 # PROP Ignore_Export_Lib 0
 # PROP Target_Dir ""
 # ADD BASE CPP /nologo /W3 /Gm /GX /ZI /Od /D "WIN32" /D "_DEBUG" /D "_CONSOLE" /D "_MBCS" /YX /FD /GZ /c
-# ADD CPP /nologo /MTd /W3 /GX /Zi /Od /I ".." /D "WIN32" /D "_DEBUG" /D "_CONSOLE" /D "_MBCS" /D "MAIN_TEST" /FR /FD /GZ /c
+# ADD CPP /nologo /MTd /W3 /GX /Zi /Od /I ".." /D "WIN32" /D "_DEBUG" /D "_CONSOLE" /D "_MBCS" /D "GRID_TEST" /FR /FD /GZ /c
 # SUBTRACT CPP /YX
 # ADD BASE RSC /l 0x409 /d "_DEBUG"
 # ADD RSC /l 0x409 /d "_DEBUG"
@@ -86,6 +86,10 @@ LINK32=link.exe
 # Name "stb - Win32 Debug"
 # Begin Source File
 
+SOURCE=.\grid_reachability.c
+# End Source File
+# Begin Source File
+
 SOURCE=..\docs\other_libs.md
 # End Source File
 # Begin Source File
diff --git a/tests/test_c_compilation.c b/tests/test_c_compilation.c
index de25330..3f4148c 100644
--- a/tests/test_c_compilation.c
+++ b/tests/test_c_compilation.c
@@ -9,6 +9,7 @@
 #define STB_RECT_PACK_IMPLEMENTATION
 #define STB_VOXEL_RENDER_IMPLEMENTATION
 #define STB_EASY_FONT_IMPLEMENTATION
+#define STB_CONNECTED_COMPONENTS_IMPLEMENTATION
 
 #include "stb_easy_font.h"
 #include "stb_herringbone_wang_tile.h"
@@ -21,6 +22,10 @@
 #include "stb_image_resize.h"
 #include "stb_rect_pack.h"
 
+#define STBCC_GRID_COUNT_X_LOG2  10
+#define STBCC_GRID_COUNT_Y_LOG2  10
+#include "stb_connected_components.h"
+
 #define STBVOX_CONFIG_MODE 1
 #include "stb_voxel_render.h"
 
diff --git a/tests/test_cpp_compilation.cpp b/tests/test_cpp_compilation.cpp
index 97bd2c2..4e77da5 100644
--- a/tests/test_cpp_compilation.cpp
+++ b/tests/test_cpp_compilation.cpp
@@ -8,6 +8,7 @@
 #define STB_HERRINGBONE_WANG_TILE_IMPLEMENTATION
 #define STB_RECT_PACK_IMPLEMENTATION
 #define STB_VOXEL_RENDER_IMPLEMENTATION
+#define STB_CONNECTED_COMPONENTS_IMPLEMENTATION
 
 #define STBI_MALLOC     my_malloc
 #define STBI_FREE       my_free
@@ -27,6 +28,10 @@ void my_free(void *) { }
 #include "stb_divide.h"
 #include "stb_herringbone_wang_tile.h"
 
+#define STBCC_GRID_COUNT_X_LOG2  10
+#define STBCC_GRID_COUNT_Y_LOG2  10
+#include "stb_connected_components.h"
+
 #define STBVOX_CONFIG_MODE 1
 #include "stb_voxel_render.h"
 
diff --git a/tests/test_truetype.c b/tests/test_truetype.c
index 4b78152..d18d3b5 100644
--- a/tests/test_truetype.c
+++ b/tests/test_truetype.c
@@ -3,13 +3,13 @@
 #include "stb_truetype.h"
 #include "stb_image_write.h"
 
+#ifdef TT_TEST
+
 #include <stdio.h>
 
 char ttf_buffer[1<<25];
 unsigned char output[512*100];
 
-#ifdef TT_TEST
-
 void debug(void)
 {
    stbtt_fontinfo font;