Comments, documentation (#1121)

extra_fonts/README.txt

@@ -96,7 +96,9 @@
  EMBEDDING FONT IN SOURCE CODE
 ---------------------------------
 
- Compile and use 'binary_to_compressed_c.cpp' to create a compressed C style array. Then load the font with:
+ Compile and use 'binary_to_compressed_c.cpp' to create a compressed C style array. 
+ See the documentation in binary_to_compressed_c.cpp for instruction on how to use the tool.
+ Then load the font with:
  
    ImFont* font = io.Fonts->AddFontFromMemoryCompressedTTF(compressed_data, compressed_data_size, size_pixels, ...);
    

extra_fonts/binary_to_compressed_c.cpp

@@ -7,12 +7,17 @@
 // Note that even with compression, the output array is likely to be bigger than the binary file..
 // Load compressed TTF fonts with ImGui::GetIO().Fonts->AddFontFromMemoryCompressedTTF()
 
-// Single file application, build with:
-//  # cl.exe binary_to_compressed_c.cpp
-//  # gcc binary_to_compressed_c.cpp
-// etc.
+// Build with, e.g:
+//   # cl.exe binary_to_compressed_c.cpp
+//   # gcc binary_to_compressed_c.cpp
 // You can also find a precompiled Windows binary in the binary/demo package available from https://github.com/ocornut/imgui
 
+// Usage:
+//   binary_to_compressed_c.exe [-base85] [-nocompress] <inputfile> <symbolname>
+// Usage example:
+//   # binary_to_compressed_c.exe myfont.ttf MyFont > myfont.cpp
+//   # binary_to_compressed_c.exe -base85 myfont.ttf MyFont > myfont.cpp
+
 #define _CRT_SECURE_NO_WARNINGS
 #include <stdio.h>
 #include <string.h>