I can draw a line or a circle on a 256-color bitmap, because operating 256-color bitmap file is a easy stuff, just like VGA mode 13H.But now I want to show more information on my bitmap,something like a sentence.I dont know how to do it.:( The biggest problem is how to graw outline with truetype font file.I must read data from ttf file while I dont want to use winAPI,how can I do it?

Not using the Win32 API (or some other existing library) is asking for a lot of pain. TrueType is a vector font format, which means that the file contains a series of vector-based drawing instructions for each character in that font. You'd need to decode the file, interpret the instructions, and then carry them out manually.

It's so much trouble that I don't know of a single programmer who has ever done it that wasn't working on the TTF subsystem of, say, a windowing system.

Try FreeType.