411 REFERENCE · Wikibooks
Rebol Programming/scroll-para
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USAGE:
SCROLL-PARA tf sf
DESCRIPTION:
Scroll a text face, given a scroller/slider face.
SCROLL-PARA is a function value.
ARGUMENTS
tf -- Text face to scroll (Type: any)
sf -- Scroller face (Type: any)
SOURCE CODE
scroll-para: func [
"Scroll a text face, given a scroller/slider face."
tf "Text face to scroll"
sf "Scroller face"
/local tmp
][
if none? tf/para [exit]
tmp: tf/para/margin + tf/para/origin + size-text tf
tmp: min 0x0 tf/size - tmp - either tf/edge [2 * tf/edge/size] [0x0]
either sf/size/x > sf/size/y [tf/para/scroll/x: sf/data * first tmp] [
tf/para/scroll/y: sf/data * second tmp
]
show tf
]