NAME

TextLength: Determine raster length of text data.

SYNOPSIS

length = TextLength(rp, string, count)
D0 A1 A0 D0:16

WORD TextLength(struct RastPort *, STRPTR, WORD);

FUNCTION

This graphics function determines the length that text data would occupy if output to the specified RastPort with the current attributes. The length is specified as the number of raster dots: to determine what the current position would be after a Write() using this string, add the length to cp_x (cp_y is unchanged by Write()). Use the newer TextExtent() to get more information.

INPUTS

rp: a pointer to the RastPort which describes where the text attributes reside.
string: the address of string to determine the length of
count: the string length. If zero, there are no characters in the string.

RESULT

length: the number of pixels in x this text would occupy, not including any negative kerning that may take place at the beginning of the text string, nor taking into account the effects of any clipping that may take place.

NOTES

Prior to V36, the result length occupied only the low word of d0 and was not sign extended into the high word.

BUGS

A length that would overflow single word arithmetic is not calculated correctly.