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/****************************************************************************
*
* ftsizes.h
*
* FreeType size objects management (specification).
*
* Copyright (C) 1996-2020 by
* David Turner, Robert Wilhelm, and Werner Lemberg.
*
* This file is part of the FreeType project, and may only be used,
* modified, and distributed under the terms of the FreeType project
* license, LICENSE.TXT. By continuing to use, modify, or distribute
* this file you indicate that you have read the license and
* understand and accept it fully.
*
*/
/**************************************************************************
*
* Typical application would normally not need to use these functions.
* However, they have been placed in a public API for the rare cases where
* they are needed.
*
*/
#ifndef FTSIZES_H_
#define FTSIZES_H_
#include <ft2build.h>
#include FT_FREETYPE_H
#ifdef FREETYPE_H
#error "freetype.h of FreeType 1 has been loaded!"
#error "Please fix the directory search order for header files"
#error "so that freetype.h of FreeType 2 is found first."
#endif
FT_BEGIN_HEADER
/**************************************************************************
*
* @section:
* sizes_management
*
* @title:
* Size Management
*
* @abstract:
* Managing multiple sizes per face.
*
* @description:
* When creating a new face object (e.g., with @FT_New_Face), an @FT_Size
* object is automatically created and used to store all pixel-size
* dependent information, available in the `face->size` field.
*
* It is however possible to create more sizes for a given face, mostly
* in order to manage several character pixel sizes of the same font
* family and style. See @FT_New_Size and @FT_Done_Size.
*
* Note that @FT_Set_Pixel_Sizes and @FT_Set_Char_Size only modify the
* contents of the current 'active' size; you thus need to use
* @FT_Activate_Size to change it.
*
* 99% of applications won't need the functions provided here, especially
* if they use the caching sub-system, so be cautious when using these.
*
*/
/**************************************************************************
*
* @function:
* FT_New_Size
*
* @description:
* Create a new size object from a given face object.
*
* @input:
* face ::
* A handle to a parent face object.
*
* @output:
* asize ::
* A handle to a new size object.
*
* @return:
* FreeType error code. 0~means success.
*
* @note:
* You need to call @FT_Activate_Size in order to select the new size for
* upcoming calls to @FT_Set_Pixel_Sizes, @FT_Set_Char_Size,
* @FT_Load_Glyph, @FT_Load_Char, etc.
*/
FT_EXPORT( FT_Error )
FT_New_Size( FT_Face face,
FT_Size* size );
/**************************************************************************
*
* @function:
* FT_Done_Size
*
* @description:
* Discard a given size object. Note that @FT_Done_Face automatically
* discards all size objects allocated with @FT_New_Size.
*
* @input:
* size ::
* A handle to a target size object.
*
* @return:
* FreeType error code. 0~means success.
*/
FT_EXPORT( FT_Error )
FT_Done_Size( FT_Size size );
/**************************************************************************
*
* @function:
* FT_Activate_Size
*
* @description:
* Even though it is possible to create several size objects for a given
* face (see @FT_New_Size for details), functions like @FT_Load_Glyph or
* @FT_Load_Char only use the one that has been activated last to
* determine the 'current character pixel size'.
*
* This function can be used to 'activate' a previously created size
* object.
*
* @input:
* size ::
* A handle to a target size object.
*
* @return:
* FreeType error code. 0~means success.
*
* @note:
* If `face` is the size's parent face object, this function changes the
* value of `face->size` to the input size handle.
*/
FT_EXPORT( FT_Error )
FT_Activate_Size( FT_Size size );
/* */
FT_END_HEADER
#endif /* FTSIZES_H_ */
/* END */