Drawing-Buffer Size

The drawing-buffer size varies depending on the contents set for Redraw of a graphic function.

To set Redraw, click Preferences → Appearance → Display Setup from the Edit menu in the session window. Select Graphics from Category.

Selecting Host from the optional items of Redraw requires no buffer.

If you select Retained, the graphic execution module stores all redrawing data into a buffer. Such a buffer is called a retained buffer. The buffer size varies depending on the complexity of the graphic data from an application program. For example, a simple table has a buffer size of 10 KB to 20 KB, while a complicated graphic image has a buffer size of 200 KB to 300 KB.

When you select Bitmap to set Redraw, the buffer size will be the same as the sum of the retained buffer size and compatible bit map size:

(Height) x (Width) x (Number of planes) x (Bits/Pixel) / 8 bytes

For example, when you select a 7x12 font for a VGA 16-Color Display Model 2 (24x80), the bitmap size is:

(7x80) x (12x24) x 1 x 4 / 8 = 80 KB

When you select a 12x20 font for an IBM® PS/55 High-Resolution 256-Color Display Model 2, the bitmap size is:

(12x80) x (20x24) x 1 x 8 / 8 = 460 KB