Meaning of some Paint constants in Android

Question

There are a few Paint constant in Android about which I couldn't find much info. Could anyone help me with a bit of explanation about those flags:

• LINEAR_TEXT_FLAG
• SUBPIXEL_TEXT_FLAG
• FILTER_BITMAP_FLAG

Is 'subpixel' mode something close to ClearType or is it something altogether different?

Answer 1

SUBPIXEL is indeed for sub-pixel antialiasing, which is currently not supported on Android. Setting this flag will have no effect. FILTER_BITMAP is used to apply bilinear filtering to bitmaps when they are transformed (scaled for instance.) It's usually a good idea to enable FILTER_BITMAP unless speed matters (much) more than quality. LINEAR_TEXT is used to draw text at a 64px text size with a scale factor set to your textSize/64.