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OGLFT::Grayscale Class Reference

Render text as a grayscale raster image. More...

#include <OGLFT.h>

Inheritance diagram for OGLFT::Grayscale::

OGLFT::Raster OGLFT::Face List of all members.

Public Methods

 Grayscale (const char *filename, float point_size=12, FT_UInt resolution=100)
 Grayscale (FT_Face face, float point_size=12, FT_UInt resolution=100)
 ~Grayscale (void)

Detailed Description

Render text as a grayscale raster image.

grayscale_class.png
The Grayscale style is similar to the Monochrome style. FreeType is used to rasterize a glyph and this is then drawn on the screen using glDrawPixels. The FreeType rasterization is done in anti-aliased mode. When Grayscale draws the glyph image, the resulting text is blended smoothly from the foreground color to the background color. The background of the glyph is opaque, so this style works best over a solid background.

Note: you must call

 glPixelStorei( GL_UNPACK_ALIGNMENT, 1 );
before drawing in order for grayscale glyphs to be rendered properly.

Another note: It is helpful to have the option GL_RASTER_POSITION_UNCLIPPED_IBM available if you intend to draw text at MODELVIEW based positions, otherwise if the initial text position is off the screen, the entire image is clipped.


Constructor & Destructor Documentation

OGLFT::Grayscale::Grayscale ( const char * filename,
float point_size = 12,
FT_UInt resolution = 100 )
 

Parameters:
file   the filename which contains the font face.
point_size   the initial point size of the font to generate. A point is essentially 1/72th of an inch. Defaults to 12.
resolution   the pixel density of the display in dots per inch (DPI). Defaults to 100 DPI.

OGLFT::Grayscale::Grayscale ( FT_Face face,
float point_size = 12,
FT_UInt resolution = 100 )
 

Parameters:
face   open FreeType FT_Face.
point_size   the initial point size of the font to generate. A point is essentially 1/72th of an inch. Defaults to 12.
resolution   the pixel density of the display in dots per inch (DPI). Defaults to 100 DPI.

OGLFT::Grayscale::~Grayscale ( void )
 

The destructor doesn't do anything in particular.


The documentation for this class was generated from the following files:
Generated at Fri Jul 12 10:47:15 2002 for OGLFT by doxygen1.2.8.1 written by Dimitri van Heesch, © 1997-2001