在JDK的TrueTyepFont类中，看到以下注释：
/*
This is to obtain info from the TT 'gasp' (grid-fitting and
scan-conversion procedure) table which specifies three combinations:
Hint, Smooth (greyscale), Hint and Smooth.
In this simplified scheme we don't distinguish the latter two. We
hint even at small sizes, so as to preserve metrics consistency.
If the information isn't available default values are substituted.
The more precise defaults we'd do if we distinguished the cases are:
Bold (no other style) fonts :
0-8 : Smooth ( do grey)
9+ : Hint + smooth (gridfit + grey)
Plain, Italic and Bold-Italic fonts :
0-8 : Smooth ( do grey)
9-17 : Hint (gridfit)
18+ : Hint + smooth (gridfit + grey)
The defaults should rarely come into play as most TT fonts provide
better defaults.
REMIND: consider unpacking the table into an array of booleans
for faster use.
*/
@Override
public boolean useAAForPtSize(int ptsize) {
