RE: [ft] reading glyph bitmap

[Minhaj Ahmed]

Here is the sample code which fails to retrieve the bitmap glyph properly, I 
see all white space with a 
...................

at the end for number 3 for example..yet example1.c here 
 http://freetype.freedesktop.org/freetype2/docs/tutorial/
works well with letters/numbers oriented as provided in the original email 
below...
/////////////////////////////////////////////////////////
//
void PrintLetter(
                  unsigned char *my_buf, //this buffer is 
face->glyph->bitmap->buffer
                  FT_Bitmap *bmp //same bitmap struct to which the buffer above 
belongs
)
{
        FT_Int i, j, p;
        FT_Int x_max = bmp->pitch;
        FT_Int y_max = bmp->rows;

        //
        // i each time should equal the first pixel in each row and 
        // should move upward every iteration
        // j would print one by one each byte in a given row
        //
        for (i = (y_max-1)*x_max, p = 0; p < y_max ; i-=x_max, p++ )
        {
                for ( j = i; j < x_max; j++)
                {
                        putchar(my_buf[j] == 0 ? ' ' : my_buf[j] < 128 ? '-' : 
'.');
                }
                putchar('\n');
        }
}

________________________________________
From: Werner LEMBERG address@hidden
Sent: Wednesday, September 01, 2010 10:39 AM
To: Minhaj Ahmed
Subject: Re: [ft] reading glyph bitmap

> Thanx for the reply, I am using exactly the same method & it works
> but orients the glyph horizontally, was wondering why I am unable to
> read it row by row instead?

Without a (working) code snippet, I can't help.  And please don't
write to me privately but to the freetype list.


    Werner

From: Minhaj Ahmed
Sent: Tuesday, August 31, 2010 4:30 PM
To: address@hidden
Subject: reading glyph bitmap

Hope I am sending this on the right email list.  I am new to fonts in general 
and am trying to render the bitmap of various glyphs on to a label.  I can only 
read the bitmap using the index

 

y_offset * width_of_bmp + x_offset .  Starting for x and y offsets of 0 this as 
expected reads in the first vertical line in the bitmap into the first scanline 
and orients the glyph horizontally.  Every time I’ve tried to scan the bitmap 
from top left down or from bottom left up I’ve failed.  Can anybody explain 
why?  Also how do you flip the glyph, I ask because rotation is not enough to 
fix the glyph read in the way I’ve been able to so far.  Thanx in advance!

 

 

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