Add -o parameter support for gfx font converter.

Improve documentation.

README.md

@@ -10,7 +10,10 @@ And there is nothing between.
 
 Here, I started to fill this gap with the class library for the common embedded developers' tasks I faced in my own projects.
 Also, it contains a common hardware interface (SPI, I2C, UART, RTC, etc) mapped to the framework-specific implementations.
-Currently, ESP-IDF is supported, and the root CMake file is fully integrated into its native build system. The STM32-specific version is under development. And to make the transition fluent there is also an Arduino-based backend integrated with PlatformIO.
+Currently, there are three ways to use library:
+- ESP-IDF framework, can be imported as a component. The CMake file is fully integrated into its native build system.
+- PlatformIO framework (Arduino backend). The library.json file is provided, so it can be imported as a library in the PlatformIO projects.
+- A standalone CMake project. The CMakeLists.txt can be used as a standalone CMake project, the tests are provided in this way.
 
 ## The main concepts
 
@@ -79,22 +82,38 @@ EXPECT_EQ(*retrievedObject, testObject);
 This library contains various graphics primitives, fonts and frame buffer.
 See the [Readme](graphics/Readme.md) for details.
 
+## GFX Font Converter
+
+This is a console utility to convert the font from the TTF format to the GFX format used by the graphics library.
+For the 7 bit (ASCII) charset it's compatible with the Adafruit GFX library.
+For the 8 bit charset it's possible to specify the codepage to map one-byte character codes to the Unicode code points for rendering.
+The non-printable codes between 0X7E and 0XA0 are omitted to save space.
+Another difference is to create two binary files instead of C++ generated code. One for the font itself and another for the glyph metrics.
+The utility is written in C++ and uses FreeType library to render the glyphs.
+The suppported command line options are:
+- -f, --font - the path to the TTF font file
+- -s, --size - the output font size in points
+- -d, --dpi - the output font resolution in DPI, default 141
+- -e, --encoding - charset to use, default is ASCII (7-bit)
+- -b - use binary format for the font data (default is generated C++ header)
+- -o, --output - the output directory, default the executable's one.
+
 ## Hardware-independent interfaces
 
 The library contains the hardware-independent interfaces for the common hardware:
 - SpiDevice
-  - sendSync() - half-duplex send
-  - receiveSync() - half-duplex receive
-  - sendAndReceive() - full-duplex send and receive
+  - sendSync() - half-duplex blocking send
+  - receiveSync() - half-duplex blocking receive
+  - sendAndReceive() - full-duplex blocking send and receive
 - I2CDevice
-  - sendSync() - send
-  - receiveSync() - receive
+  - sendSync() - blocking send with timeout
+  - receiveSync() - blocking receive with timeout
 - PacketUart
-  - sendSync() - send
-  - receiveSync() - receive
-  - receiveUntil() - receive until the specified byte is received
-  - receiveBetween() - receive a packet betwiin specified start and stop bytes
+  - sendSync() - blocking send with timeout
+  - receiveSync() - blocking receive with timeout
+  - receiveUntil() - blocking receive until the specified byte is received or timeout happened
+  - receiveBetween() - blocking receive a packet between specified start and stop bytes, which are included in the result
 
 ## Hardware-specific implementations
 
-Currencly Arduino and ESP-IDF frameworks are supported.
+Currently, ESP32 and generic Arduino are supported. STM32 native implementation is under development.

gfx-font-converter/FontConverterConfig.cpp

@@ -16,7 +16,7 @@ FontConverterConfig::FontConverterConfig(int argc, char** argv)
                 fontFileName = optarg;
                 break;
             case 'o':
-                outputFileName = optarg;
+                outputDirectory = optarg;
                 break;
             case 'd':
                 DPI = std::stoi(optarg);

gfx-font-converter/FontConverterConfig.h

@@ -9,7 +9,7 @@ class FontConverterConfig
     enum class Format { Header, Binary};
     FontConverterConfig(int argc, char * argv[]);
     const std::string& getFontFileName() const { return fontFileName; }
-    const std::string& getOutputFileName() const { return outputFileName; }
+    const std::string& getOutputDirectory() const { return outputDirectory; }
     const std::string& getEncoding() const { return encoding; }
     int getDPI() const { return DPI; }
     int getFontSize() const { return fontSize; }
@@ -19,7 +19,7 @@ class FontConverterConfig
     bool getPrintHelp() const { return printHelp; }
 private:
     std::string fontFileName;
-    std::string outputFileName;
+    std::string outputDirectory;
     std::string encoding;
     int DPI = 141;
     int fontSize = 12;

gfx-font-converter/main.cpp

@@ -259,7 +259,7 @@ int main(int argc, char* argv[])
     if (config.getPrintHelp() || fontFileName.empty())
     {
         std::cout << "Usage: " << std::filesystem::path(argv[0]).filename().string()
-                  << " -f fontfile [-o outputfile] [-d DPI] [-s size] [-l last char] [-e 8-bit codepage, default ISO-8859-1] [-h]"
+                  << " -f fontfile [-o outputfile] [-d DPI] [-s size] [-e 8-bit codepage, default ISO-8859-1] [-b] [-h]"
                   << std::endl;
         return 1;
     }
@@ -271,7 +271,8 @@ int main(int argc, char* argv[])
                 fontName =
                 fontFilePath.filename().replace_extension("").string() + std::to_string(config.getFontSize()) + "pt" +
                 std::to_string(config.getLastChar() > 127 ? 8 : 7) + "b";
-        auto outputDir = std::filesystem::path(argv[0]).parent_path();
+        auto outputDir = std::filesystem::is_directory(config.getOutputDirectory()) ?
+                         std::filesystem::path(config.getOutputDirectory()) : std::filesystem::path(argv[0]).parent_path();
 
         const auto dpi = config.getDPI();
         const FT_F26Dot6 fontSize = config.getFontSize() << 6;

graphics/Readme.md

@@ -45,29 +45,13 @@ It provides the following operations:
 
 ## EmbeddedFonts(.h/.cpp)
 
-As an entry point for fonts used in application it declare and define a set of `EmbeddedFont` objects.
-EmbeddedFonts.cpp contains a template for adding new fonts.
+For the fonts converted to the C++ headers used in application it declares and define a set of `EmbeddedFont` objects.
+EmbeddedFonts.cpp contains an example font definition and can be used as a template for adding new fonts.
 It maps the GFX font definition files to `EmbeddedFont` objects.
 The font definition files are located in `GFXFonts` directory. Initially it contains the following fonts:
 * `FreeSans15pt7b`
 
-The default font converter from Adafruit as well as online services available create a font file definition
-with the C-style type casting of arrays. Instead, the adapter classes expect arrays for size deduction.
-So you could modify the converter of just manually remove the castings like this:
-```c++
-// Original
-const GFXfont FreeSans15pt7b PROGMEM = {
-(uint8_t  *)FreeSans15pt7bBitmaps,
-(GFXglyph *)FreeSans15pt7bGlyphs,
-0x20, 0x7E, 35 };
-
-// Modified
-const GFXfont FreeSans15pt7b PROGMEM = {
-FreeSans15pt7bBitmaps,
-FreeSans15pt7bGlyphs,
-0x20, 0x7E, 35 };
-```
-
 ## GFXFontsAdapter.h
 
 Contains font and glyph adapters for GFX-compatible fonts.
+It can be initialized from the embedded binary data or with the arrays from the generated C++ header

library.json

@@ -3,7 +3,7 @@
   "name": "General Support Library",
   "version": "1.0.0",
   "description": "General C++ library for embedded development.",
-  "keywords": "C++17, esp32",
+  "keywords": "C++17, esp32, graphics, fonts",
   "repository":
   {
     "type": "git",