Problem with bitmap font in texture atlas with retina version of atlas texture

noamgat

Hi,

In my game, I have the following structure :
1) Bitmap font was generated and I got .fnt and .png files.
2) I embedded the .png into a texture atlas.
3) I generated a @2x version of the texture atlas. Some of the textures have double size versions, others just get supersampled. The bitmap font gets supersampled.

When I try to display letters from the bitmap font under retina, they show in the wrong positions. This is because the scale factor of the texture affects the texture coordinates twice : the width of the base texture is 2 and the SPSubTexture also reports its scale as 2, so the division by two happens twice.

I can fix this problem locally by changing SPSubTexture's scale to return 1 instead of returning its base texture's scale. This seems correct as the width and height that it reports are already affected by the scale.

However, I do not want to create a separate version of sparrow.
Does this change make sense? Am I doing something wrong and this is just a fix to that wrong-doing?

noamgat

Solved-ish : I generated a double size bitmap font, and now the atlases that I generate do not use the same texture for the font, so each version loads a different .fnt file and a different texture from the atlas. Now the coordinates in the .fnt file are double size, so it works.

Daniel

Yes, unfortunately it's quite tricky to add the font texture to an atlas when working with multiple resolutions, because the textures of the different font sizes are not exactly equivalent. There's no easy workaround for that, unfortunately!