ref: a7b53c47fca0520636b633e3b812ef6313ea1891
parent: 6b0bf34665059d437995a5dabc53975ad3ecf8f7
author: David Turner <[email protected]>
date: Thu Jun 1 02:01:59 EDT 2000
changed an important comment note for FT_Size_Metrics describing the ascender, descender and text height..
--- a/include/freetype/freetype.h
+++ b/include/freetype/freetype.h
@@ -837,10 +837,17 @@
/* fixed point pixels. Always positive. */
/* */
/* <Note> */
- /* This structure doesn't return the vertical ascender, descender, */
- /* and height, as well as a few other esoteric properties. One can */
- /* however compute these through the size's x_scale and y_scale, */
- /* applied to the relevant face properties. */
+ /* The values of "ascender", "descender" and "height" are only the */
+ /* scaled versions of "face->ascender", "face->descender" and */
+ /* "face->height". */
+ /* */
+ /* Unfortunately, due to glyph hinting, these values might not be */
+ /* exact for certain fonts, they thus must be treated as unreliable */
+ /* with an error margin of at least one pixel !! */
+ /* */
+ /* Indeed, the only way to get the exact pixel ascender and descender */
+ /* is to render _all_ glyphs. As this would be a definite performance */
+ /* hit, it's up to client applications to perform such computations.. */
/* */
typedef struct FT_Size_Metrics_
{