Re: [ft-devel] Having trouble rendering emojis with FreeType

[Moazin Khatri]

Hi Werner,

Pleased to inform you that you were right about the size not being correct. I just changed the line to:

FT_Error err = FT_Set_Char_Size(face, 6976, 0, 72, 72);

The program just works fine now. Just rendered an emoji on console, works totally fine! 

The way I figured these sizes out is that I ran `ftview' in gdb and followed the code to a point where it sets the sizes. I just grabbed the size from there and everything works just fine. I still need to understand the exact steps `ftview' takes to calculate these sizes and why it does that. Too tired for it today, so I am calling it a night. Will do that very soon. 

Thank you for telling me about `ftview'. I have seen it mentioned at places, but had no idea it was such a nicely written tool. Had I known about it earlier, I would have figured this out quicker. 

Regards,

Moazin

On Wed, May 15, 2019 at 10:48 PM Werner LEMBERG <address@hidden> wrote:

Moazin,


the `ftview' demo program displays the font in question just fine, so
maybe it makes sense to check this program how it works.  Probably
tomorrow I will check your code – but maybe you are faster than me in
identifying the error :-)

> *What's the problem?*
>
> If I call `FT_Set_Char_Size' in the program, it returns error code
> 0x17 which is `Invalid Pixel Size'.

The ppem value is 109.

> Secondly, `FT_Load_Glyph' returns error code 0x24 which is `Invalid
> Size Handle'. `FT_Load_Glyph' returns the same even if I don't call
> `FT_Set_Char_Size' at all.

This is a consequence of not selecting the right ppem value, I guess.


    Werner