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Diffstat (limited to 'ipl/gprogs/etch.icn')
| -rw-r--r-- | ipl/gprogs/etch.icn | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/ipl/gprogs/etch.icn b/ipl/gprogs/etch.icn new file mode 100644 index 0000000..d491554 --- /dev/null +++ b/ipl/gprogs/etch.icn @@ -0,0 +1,153 @@ +############################################################################ +# +# File: etch.icn +# +# Subject: Program for distributed Etch-A-Sketch +# +# Author: Clinton L. Jeffery +# +# Date: June 17, 1994 +# +############################################################################ +# +# This file is in the public domain. +# +############################################################################ +# +# A drawing program. Invoked with one optional argument, the +# name of a remote host on which to share the drawing surface. +# +# Dragging the left button draws black dots +# The middle button draws a line from button press to the release point +# The right button draws white dots +# Control-L clears the screen +# The Escape character exits the program +# +############################################################################ +# +# Requires: Version 9 graphics +# +############################################################################ +# +# Links: wopen, xcompat +# +############################################################################ + +link wopen +link xcompat + +procedure main(av) + local w1, w2, w3, w4, w5, w6, w, x1, xa, x2, xb, y1, ya, y2, yb, dragging, + da, xc, xd, yc, yd, dc, e + # + # open an etch window. If there was a command line argument, + # attempt to open a second window on another display. For + # each window, create a binding with reverse video for erasing. + # + w1 := WOpen("label=etch", "size=300,300") | stop("can't open window") + w2 := XBind(w1,"drawop=xor") | stop("can't XBind w2") + w3 := XBind(w1,"reverse=on") | stop("can't XBind w3") + if *av>0 then { + w4 := WOpen("label=etch", "display="||av[1]||":0","size=300,300") | + stop("can't open window, display=",av[1]) + w5 := XBind(w4,"drawop=xor") | stop("Can't XBind w5") + w6 := XBind(w4,"reverse=on") | stop("Can't XBind w6") + } + repeat { + # + # wait for an available event on either display + # + w := Active() | stop("Active fails") + if (w === (w1|w2)) then { + x1 := xa + x2 := xb + y1 := ya + y2 := yb + dragging := da + } else { + x1 := xc + x2 := xd + y1 := yc + y2 := yd + dragging := dc + } + + case e := Event(w) of { + # + # Mouse down events specify an (x1,y1) point for later drawing. + # (x2,y2) is set to null; each down event starts a new draw command. + # + &lpress | &mpress | &rpress: { + x1 := &x + y1 := &y + x2 := y2 := &null + } + # + # Mouse up events obtain second point (x2,y2), and draw a line. + # + &lrelease: { + DrawLine(w1,\x1,\y1,&x,&y) + DrawLine(\w4,\x1,\y1,&x,&y) + } + &mrelease: { + DrawLine(w1,x1,y1,&x,&y) + DrawLine(\w4,x1,y1,&x,&y) + dragging := &null + } + &rrelease: { + DrawLine(w3,x1,y1,&x,&y) + DrawLine(\w6,x1,y1,&x,&y) + } + # + # Drag events obtain a second point, (x2,y2), and draw a line + # If we are drawing points, we update (x1,y1); if we are + # drawing lines, we erase the "rubberband" line and draw a new + # one at each drag event; a permanent line will be drawn when + # the button comes up. + # + &ldrag : { + DrawLine(w1,x1,y1,&x,&y) + DrawLine(\w4,x1,y1,&x,&y) + # left and right buttons use current position + x1 := &x # for subsequent operations + y1 := &y + } + &rdrag : { + DrawLine(w3,x1,y1,&x,&y) + DrawLine(\w6,x1,y1,&x,&y) + # left and right buttons use current position + x1 := &x # for subsequent operations + y1 := &y + } + &mdrag: { + if /dragging then dragging := 1 + else { # erase previous line, if any + DrawLine(w2,x1,y1,\x2,\y2) + DrawLine(\w5,x1,y1,\x2,\y2) + } + x2 := &x + y2 := &y + DrawLine(w2,x1,y1,x2,y2) + DrawLine(\w5,x1,y1,x2,y2) + } + "\^l": { + EraseArea(w1) + EraseArea(\w4) + } + "\e": break + } + if (w === (w1|w2)) then { + xa := x1 + xb := x2 + ya := y1 + yb := y2 + da := dragging + } else { + xc := x1 + xd := x2 + yc := y1 + yd := y2 + dc := dragging + } + } +end |