Wraps TTF_GetFontSDF (from SDL_ttf 2.0.18) to get whether the dsdl2.ttf.Font has signed distance field
true if the dsdl2.ttf.Font has SDF, otherwise false
See Implementation
Wraps TTF_GetFontSDF (from SDL_ttf 2.0.18) to get whether the dsdl2.ttf.Font has signed distance field