The samples on this page demonstrate TrueDoc's use of anti-aliasing and subpixel positioning for on-screen rendering. These features let you smooth jagged edges on the screen and fine tune the space between characters on lines of type.

The following samples show two of TrueDoc's formidable features, anti-aliasing and subpixel positioning.

Anti-aliasing smooths jagged edges on the screen by using gradations of gray. Using TrueDoc, you can specify the number of grayscale levels you want. The samples below show images rendered in black and white (no anti-aliasing) and sixteen grayscale levels.

The sample above uses no anti-aliasing. Note how the larger type appears jagged.

The sample above uses sixteen grayscale levels to anti-alias the rendered images.

Subpixel positioning lets you more accurately compose lines of type when rendering bitmap images. This results in better characters spacing.

In most cases, you use a bitmap cache when playing back characters. You play back the character once, store it in the cache, then take it from the cache the next time you use it. This saves you the overhead of regenerating the character each time you need to rasterize it for the screen.

When using a bitmap cache, you assume that a bitmap image does not change in respect to its position on a pixel grid. You can re-use a bitmap image any time you run across its character at the same point size, same rotation angle, and in the same font.

However, you can only render a bitmap image of a character on the nearest pixel boundary to its real position. This results in a plus-or-minus, half-pixel inaccuracy in the rendered position of each character, which shows up as poor intercharacter spacing. To get around this problem, TrueDoc lets you render characters between pixel boundaries, useful on screen displays that support grayscale output (most displays do). With TrueDoc, you can set character positioning, in both x and y, from whole pixels up to 1/16 subpixels.

The samples below show rotated text, first with no subpixel positioning, then with 1/16 pixel positioning.

		The sample to the left uses no subpixel positioning. Note how the "u" in "Source" and the "c" in "code" (first line), as well as the "s" in "resource" (second line), seem to float up. Also note the uneven spacing among the letters "hnolog" in "technology."
		The sample to the left uses 1/16 pixel positioning. This corrects the spacing problems noted in the previous sample.