ÿþThe way to do it is to first go to ttinterp.c , then at the start of the file declare two variables: char FT_injectedGETINFOhack = 0; FT_Long FT_injectedGETINFOhackvalue; Now here's the tricky part. Go near line 7660 and find the ending of the GETINFO function. It would look something like this: #endif /* TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY */ args[0] = K; } So the way to add the intercept is to then proceed to add code to overwrite the value: #endif /* TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY */ if(FT_injectedGETINFOhack){ K = FT_injectedGETINFOhackvalue; } args[0] = K; } What will provide in it better render result? Of course, this makes the GETINFO customizable for users of FreeType (that include the FreeType files in their programs). The benefits of interception can be seen for instance in the v38 renderer. Disclaimer: The sample images are made with v38 FreeType bytecode, but the outlines are not rasterized with FreeType rasterizer. The correct gasp setting for symmetric smoothing is used in the renders, with 6×1 or 6×5 oversampling and the subpixel box filter to simulate ClearType. First of all, a commercial font is rendered like this when GETINFO is not intercepted: https://i.imgur.com/W9FSEzd.png Size 18ppem and up is where it gets very controversial in rendering. In this case what default v38 FreeType does is end up with fractional horizontal stems. Using Visual TrueType reveals that the font only does that when fractional widths are used in ClearType. However it is very worrying that this is default FreeType behavior, and no FT_RENDER_MODE_XXX is documented to use an integer width version of subpixel hinting. What happens with the intercepted GETINFO? In the following image I use the following settings: FT_injectedGETINFOhack = 1; FT_injectedGETINFOhackvalue = 0x00006C00; https://i.imgur.com/PuhGJ13.png . Suddenly the problems with fractional horizontal stems disappear. This will in fact allow the FreeType user to use a custom GETINFO value, and GETINFO (what fonts see how the renderer is like) becomes detached from the FreeType render mode (what the renderer is actually like), allowing for personalized renderer settings. However, even when the GETINFO is changed the v38 or v40 renderer is still miles from being finished, especially considering that FreeType does not even directly have a proper rasterizer for the base form of subpixel hinting.