diff --git a/stb_voxel_render.h b/stb_voxel_render.h
index 6517b3a..576926e 100644
--- a/stb_voxel_render.h
+++ b/stb_voxel_render.h
@@ -1183,7 +1183,7 @@ struct stbvox_mesh_maker
 #endif
 
 
-// The following are candidate voxel modes. Only modes 0, 1, and 20 are
+// The following are candidate voxel modes. Only modes 0, 1, and 20, and 21 are
 // currently implemented. Reducing the storage-per-quad further
 // shouldn't improve performance, although obviously it allow you
 // to create larger worlds without streaming.
@@ -1205,7 +1205,7 @@ struct stbvox_mesh_maker
 
 // not sure why I only wrote down the above "result data" and didn't preserve
 // the vertex formats, but here I've tried to reconstruct the designs...
-//     mode # 3 is wrong, one byte too large
+//     mode # 3 is wrong, one byte too large, but they may have been an error originally
 
 //            Mode:     0     1     2     3     4     5     6        10    11    12      20    21    22    23    24
 // =============================================================================================================
diff --git a/tests/test_c_compilation.c b/tests/test_c_compilation.c
index 2aa85b0..309be5a 100644
--- a/tests/test_c_compilation.c
+++ b/tests/test_c_compilation.c
@@ -7,6 +7,7 @@
 #define STB_HERRINGBONE_WANG_TILE_IMEPLEMENTATIOn
 #define STB_IMAGE_RESIZE_IMPLEMENTATION
 #define STB_RECT_PACK_IMPLEMENTATION
+#define STB_VOXEL_RENDER_IMPLEMENTATION
 
 #include "stb_herringbone_wang_tile.h"
 #include "stb_image.h"
@@ -18,6 +19,9 @@
 #include "stb_image_resize.h"
 #include "stb_rect_pack.h"
 
+#define STBVOX_CONFIG_MODE 1
+#include "stb_voxel_render.h"
+
 #define STBTE_DRAW_RECT(x0,y0,x1,y1,color)      0
 #define STBTE_DRAW_TILE(x,y,id,highlight,data)  0
 #define STB_TILEMAP_EDITOR_IMPLEMENTATION