Fonts

A Font is a collection of images that can be used to represent text on a screen.

There are various font classes that you can use, each with it's own advantages and disadvantages

Default Font

The Default Font (provided by CL_Font ) uses the current ClanLib default font provider. Currently this is CL_Font_Bitmap

Native Font

The Native Font (provided by CL_Font_Native ) uses the operating system font, stored in a pixel buffer ( CL_PixelBuffer ). On Windows, this is the standard window font. On Linux, this is a FreeType Font )

Freetype Font

The Freetype Font (provided by CL_Font_FreeType ) uses a truetype font, stored in a pixel buffer ( CL_PixelBuffer ).

Texture Font

The texture font (provided by CL_Font_Texture ) uses a font based on a pixel buffer (for example, a png file). This font imports the pixel buffer, and stores the result a texture group CL_TextureGroup. The Texture Font is faster than the Native Font and the Freetype Font. You can also import a Native font, which can be used to provide missing font glpyhs.

Vector Font

The vector font (provided by CL_Font_Vector ) uses a truetype font, stored as triangle primitives (drawn using CL_PrimitivesArray )

Constructing fonts

All fonts use a common font description class CL_FontDescription that is passed to the constructor of the desired font

Native Font

	CL_FontDescription desc;
	font_desc.set_typeface_name("tahoma");
	CL_Font_Native native_font(gc, font_desc);
	native_font.draw_text(gc, 100, 100, "Hello World");

Freetype Font

  CL_FontDescription desc;
  font_desc.set_typeface_name("myfont.ttf");
  CL_Font_Freetype freetype_font(font_desc);
  freetype_font.draw_text(gc, 100, 100, "Hello World");

Texture Font

  // To use a native font as CL_Textures's

  CL_FontDescription desc;
  font_desc.set_typeface_name("tahoma");
  CL_Font_Texture texture_font(gc, font_desc);
  texture_font.draw_text(gc, 100, 100, "Hello World");

  // To use a font from a png

  CL_FontDescription desc;
  font_desc.set_typeface_name("tahoma");
  CL_Font_Texture texture_font(gc, &pixel_buffer_font, font_positions);
  texture_font.load_font(gc, font_desc);	// Use tahoma for unknown glyphs
  texture_font.draw_text(gc, 100, 100, "Hello World");

Vector Font

  CL_FontDescription desc;
  font_desc.set_typeface_name("myfont.ttf");
  CL_Font_Vector vector_font(font_desc);
  vector_font.draw_text(gc, 100, 100, "Hello World");

ClanGUI and Fonts

If you want ClanGUI to use a custom font, instead of a native font, you will first need to register the font as follows

	CL_FontDescription font_desc;
	font_desc.set_typeface_name("GUI Font Name");
	font_desc.set_height(-21);
	font_desc.set_weight(700);
	CL_Font_Texture font_texture(gc, font_desc);
	font_desc.set_typeface_name("Custom Font Name (usually the same)");
	gui->set_named_font(font_texture, font_desc);