TweetFollow Us on Twitter

Split Button
Volume Number:7
Issue Number:6
Column Tag:HyperChat

Splitting Your Sides

By Carl J. Manaster, Globe, AZ

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

[Carl is a mining engineer and programmer whose appreciation for environments such as HyperCard and THINK Pascal is enhanced by painful memories of dBase and FORTRAN.]

Objectives

It’s endemic among HyperCard fans to try to “fill in” the gaps left by Apple. Such supplements often take the form of XCMDs and XFCNs, offering everything from standard file calls to color windows. Occasionally, the purists among us like to write these extensions in HyperTalk itself, keeping it “all in the family,” as it were. (Also, having once used TCL or MacApp, it’s hard to imagine going back to writing Pascal without such crutches - and they don’t help with code resources!)

One thing missing from HyperCard is polygonal buttons - arbitrary shapes that behave like a button. The need for these has been apparent since the first release and its Clip Art stack, where the user clicks on certain parts of the pictures to travel to related cards. Since it’s all done with transparent (rectangular) buttons, there’s a great deal of “slop” space, where a click that ought to be on a hat (for instance) is really in the rectangle of the man.

There are doubtless XCMDs available that solve this problem, and I’ve seen at least one article describing a HyperTalk-based solution; here is another.

The Basic Solution

My solution is to place buttons over each side of the polygon, and split the message chain along each button’s diagonal. The message to do this is in the stack’s script:

--1

--message split
--syntax: split(orientation,¬
----------------topMessage,bottomMessage)
--where: orientation is “/” or “\”
--topMessage is message to be called if click
------------------was in top half of target
--bottomMessage is message to be called if click
--------------------was in bottom half of target

on split
  put param(2) into topMessage
  put param(3) into bottomMessage
  put (the bottom of the target) - ¬
 (the clickV) into vDiff
  if param(1) is “/”
  then put (the clickH) - (the left of¬
 the target) into hDiff
  else put (the right of the target) - ¬
 (the clickH) into hDiff
  put vDiff * (the width of the target)¬
 > hDiff * (the height of the target)¬
 into doTop
  if doTop
  then send topMessage to target
  else send bottomMessage to target
end split

Each button’s mouseUp script calls split with the appropriate orientation and messages, thereby simulating two adjacent triangular buttons with differing mouseUp messages. With this script and the button tool, buttons can be placed around a polygon to simulate polygonal buttons.

Figure 1 - How a Split Button Simulates a Pair of Triangular Buttons

Getting Fancy

The obvious next step is to make it easier to generate polygonal buttons. The script in Listing #1, makePolyButton, does this. It tracks and records clicks until one is close to the first vertex, outlining the polygon as it is defined.

Figure 2 - Original Image with Polygonal Outline

Once all the vertices of the polygon have been entered, the maximum and minimum horizontal and vertical coördinates are determined, as well as the next-to-maximum and next-to-minimum.

A button is created whose sides are the next-to-extreme coördinates of the polygon’s vertices; most mouseUp messages reaching it will be within the polygon but not within any of the buttons around its edge.

Figure 3 - Polygon with Interior Button

Lastly, for each side of the polygon, a button is created whose mouseUp handler uses the split message to choose between the two messages that are passed to makePolyButton as parameters.

Figure 4 - Polygon with Border Buttons

Limitations and Flaws

Like most solutions, this one is imperfect; here are some of the problems associated with my implementation of polygonal buttons:

No AutoHilite or Outline

Because polygonal buttons have no single data structure where they are defined, autoHiliting is out of the question. Outlining is not impossible - a script could be written that included:

--2

choose line tool
if the script of the target¬
contains “split” and the script of¬
the target contains “/” then drag 

but it would not behave like normal outlining: painting would obscure it; moving the button would neither erase the old outline nor draw the new one; even if this were solved, erasing the old could mess up the paint layer with traces of white It is best to accept that outlining is not a feature of these polygonal buttons.

Sharp Corners Confuse

It is possible to generate polygons that are not modelled well with this technique. Indeed, the polygon used in Figures 2-4 shows some space that will report an “inside” message when certain “outside” areas are clicked (the upper right corner of the interior button, whose message is “inside”, extends beyond where border buttons cover it.) Similar mis-routing of the message chain can occur when the angles of a polygon are too sharp, and one border button overlaps another. This problem can be overcome by tweaking with the button tool, but even without such tweaking there is much less slop space than with plain, rectangular buttons.

Conclusions

The Spectrum of Solutions

There are countless ways in which a polygon may be made to act as a button in HyperCard; the methods differ in degree of resolution. The trade-off is between accuracy of representation on the one hand and programming demands, memory, and speed on the other. The roughest solution is to use rectangular buttons that more-or-less cover the polygon. At the fine end of the spectrum lie solutions such as pixel-sized buttons to fill the polygon, XCMDs, and complex scripts that rely on globals or fields to keep track of the polygon’s vertices.

Split buttons fall somewhere in the middle of the spectrum. The marginal costs over using rectangular buttons (a little programming, slightly more difficulty creating, moving, and deleting, and one more handler in the message chain) are relatively small, and the gains are significant. The accuracy is not as good as the pixel-perfect solutions (both HyperCard- and XCMD- based), but much less programming is required, and split buttons should be much faster than the HyperCard-based solutions.

This via media is realized by using each button to focus information, like relying on an airplane to get across the country and then getting to your house by car. The rough end of the spectrum relies on HyperCard to do all of the work (flying home on a 747); the fine end solutions do all of the work themselves (driving cross-country); split buttons rely on HyperCard for what it’s good at - the rough determination of which rectangular button contained the click - and concentrate on further distilling the information.

Because split buttons represent a compromise, they will not be appropriate for every stack calling for polygonal buttons. Because they represent a good compromise, however, they may find many applications.

LISTING #1 - makePolyButton script
--message makePolyButton
--syntax: makePolyButton(inMessage,outMessage)
----------inMessage is message to be called by 
----------------clicks within the polyButton
----------outMessage is message to be called by 
----------------clicks outside the polyButton

on makePolyButton inMessage,outMessage
 put empty into pointList
 choose line tool
 set the cursor to cross
 wait until the mouseClick
 put the clickLoc into pointList

 repeat
 wait until the mouseClick
 put return & the clickLoc after pointList
 put the number of lines of pointList¬
 into count
 drag from (line count-1 of pointList)¬
 to (line count of pointList)
 if abs(item 1 of last line of pointList¬
 - item 1 of first line of pointList)<2¬
 and abs(item 2 of last line of pointList¬
 - item 2 of first line of pointList)<2¬
 then exit repeat
 end repeat

 put line 1 of pointList into¬
 last line of pointList
 put the number of card buttons into cbCount
 set lockScreen to true
 doMenu revert
 choose button tool

 put item 1 of line 1 of pointList into maxV
 put item 1 of line 2 of pointList into maxPenV
 put item 1 of line 1 of pointList into minV
 put item 1 of line 2 of pointList into minPenV

 put item 2 of line 1 of pointList into maxH
 put item 2 of line 2 of pointList into maxPenH
 put item 2 of line 1 of pointList into minH
 put item 2 of line 2 of pointList into minPenH

 repeat with i=2 to count

 get item 1 of line i of pointList
 if it > maxPenV then--find the largest
 if it > maxV then --and second largest v
 put maxV into maxPenV
 put it into maxV
 else
 put it into maxPenV
 end if
 end if

 if it < minPenV then   --find the smallest
 if it < minV then --and second smallest v
 put minV into minPenV
 put it into minV
 else
 put it into minPenV
 end if
 end if

 get item 2 of line i of pointList
 if it > maxPenH then--find the largest
 if it > maxH then --and second largest h
 put maxH into maxPenH
 put it into maxH
 else
 put it into maxPenH
 end if
 end if

 if it < minPenH then--find the smallest
 if it < minH then --and second smallest h
 put minH into minPenH
 put it into minH
 else
 put it into minPenH
 end if
 end if

 end repeat

 add 1 to cbCount--create the interior button
 doMenu “new button”
 set the style of card button cbCount¬
 to transparent
 set the showName of card button cbCount¬
 to false
 set the autoHilite of card button cbCount¬
 to false
 set the rect of card button cbCount¬
 to minPenV,minPenH,maxPenV,maxPenH
 put “on mouseUp” into theScript
 put return & inMessage after theScript
 put return & “end mouseUp” after theScript
 set the script of card button cbCount¬
 to theScript
 repeat with i=1 to count-1
 add 1 to cbCount--create the edge buttons
 set the cursor to busy
 put line i of pointList into firstPoint
 put line (i+1) of pointList into secondPoint
 doMenu “new button”
 set the name of card button cbCount¬
 to “split” && i

 --determine the coördinates of the button:
 if (item 1 of firstPoint) < (item 1¬
 of secondPoint) then
 put item 1 of firstPoint into top
 put item 1 of secondPoint into bottom
 else
 put item 1 of secondPoint into top
 put item 1 of firstPoint into bottom
 end if
 if (item 2 of firstPoint) > (item 2¬
 of secondPoint) then
 put item 2 of firstPoint into right
 put item 2 of secondPoint into left
 else
 put item 2 of secondPoint into right
 put item 2 of firstPoint into left
 end if

 set the rect of card button cbCount¬
 to top,left,bottom,right
 set the style of card button cbCount¬
 to transparent
 set the showName of card button cbCount¬
 to false
 set the autoHilite of card button cbCount¬
 to false

 --determine the orientation of the
 --”split” of the button:

 put “on mouseUp” into theScript

 if (item 1 of firstPoint) > (item 1¬
 of secondPoint) then
 if (item 2 of firstPoint) > (item 2¬
 of secondPoint) then
 put return & “split “ & quote & “\”¬
 & quote & “,” & inMessage & “,” &¬
 outMessage after theScript
 else
 put return & “split “ & quote & “/”¬
 & quote & “,” & inMessage & “,” &¬
 outMessage after theScript
 end if
 else
 if (item 2 of firstPoint) > (item 2¬
 of secondPoint) then
 put return & “split “ & quote & “/”¬
 & quote & “,” & outMessage & “,” &¬
 inMessage after theScript
 else
 put return & “split “ & quote & “\”¬
 & quote & “,” & outMessage & “,” &¬
 inMessage after theScript
 end if
 end if

 put return & “end mouseUp” after theScript

 set the script of card button cbCount¬
 to theScript
 end repeat

 choose browse tool
end makePolyButton
 

Community Search:
MacTech Search:

Software Updates via MacUpdate

LooperSonic (Music)
LooperSonic 1.0 Device: iOS Universal Category: Music Price: $4.99, Version: 1.0 (iTunes) Description: LooperSonic is a multi-track audio looper and recorder that will take your loops to the next level. Use it like a loop pedal to... | Read more »
Space Grunts guide - How to survive
Space Grunts is a fast-paced roguelike from popular iOS developer, Orange Pixel. While it taps into many of the typical roguelike sensibilities, you might still find yourself caught out by a few things. We delved further to find you some helpful... | Read more »
Dreii guide - How to play well with othe...
Dreii is a rather stylish and wonderful puzzle game that’s reminiscent of cooperative games like Journey. If that sounds immensely appealing, then you should immediately get cracking and give it a whirl. We can offer you some tips and tricks on... | Read more »
Kill the Plumber World guide - How to ou...
You already know how to hop around like Mario, but do you know how to defeat him? Those are your marching orders in Kill the Plumber, and it's not always as easy as it looks. Here are some tips to get you started. This is not a seasoned platform... | Read more »
Planar Conquest (Games)
Planar Conquest 1.0 Device: iOS Universal Category: Games Price: $12.99, Version: 1.0 (iTunes) Description: IMPORTANT: Planar Conquest is compatible only with iPad 3 & newer devices, iPhone 5 & newer. It’s NOT compatible with... | Read more »
We talk to Cheetah Mobile about its plan...
Piano Tiles 2 is a fast-paced rhythm action high score chaser out now on iOS and Android. You have to tap a series of black tiles that appear on the screen in time to the music, being careful not to accidentally hit anywhere else. Do that and it's... | Read more »
Ultimate Briefcase guide - How to dodge...
Ultimate Briefcase is a simple but tricky game that’s highly dependent on how fast you can react. We can still offer you a few tips and tricks on how to survive though. Guess what? That’s exactly what we’re going to do now. Take it easy [Read more... | Read more »
SoundPrism Link Edition (Music)
SoundPrism Link Edition 1.0 Device: iOS Universal Category: Music Price: $4.99, Version: 1.0 (iTunes) Description: ***Introductory price for a the first few days after launch - if you're reading this, get it while it's fresh out of... | Read more »
Pre-register now for hack and slasher An...
Fincon, which won Facebook's Studio to Watch award in 2015, has announced that pre-registration is now open for the massive 3.0 update for its award-winning hack and slasher Angel Stone. Angel Stone is a post-apocalyptic action RPG in which the... | Read more »
Google has named Piano Tiles 2 as its Be...
Google has named Piano Tiles 2, which launched back in August last year, as its Best Game of 2015. If you're yet to play it, now's a good time to do so. It's a sequel to the hugely successful viral hit Piano Tiles (Don't Tap the White Tile) but... | Read more »

Price Scanner via MacPrices.net

Apple refurbished 2014 13-inch Retina MacBook...
Apple has Certified Refurbished 2014 13″ Retina MacBook Pros available for up to $400 off original MSRP, starting at $979. An Apple one-year warranty is included with each model, and shipping is free... Read more
Macs available for up to $300 off MSRP, $20 o...
Purchase a new Mac or iPad using Apple’s Education Store and take up to $300 off MSRP. All teachers, students, and staff of any educational institution qualify for the discount. Shipping is free, and... Read more
Watch Super Bowl 50 Live On Your iPad For Fre...
Watch Super Bowl 50 LIVE on the CBS Sports app for iPad and Apple TV. Get the app and then tune in Sunday, February 7, 2016 at 6:30 PM ET to catch every moment of the big game. The CBS Sports app is... Read more
Two-thirds Of All Smart Watches Shipped In 20...
Apple dominated the smart watch market in 2015, accounting for over 12 million units and two-thirds of all shipments according to Canalys market research analysts’ estimates. Samsung returned to... Read more
12-inch 1.2GHz Retina MacBooks on sale for up...
B&H Photo has 12″ 1.2GHz Retina MacBooks on sale for $180 off MSRP. Shipping is free, and B&H charges NY tax only: - 12″ 1.2GHz Gray Retina MacBook: $1499 $100 off MSRP - 12″ 1.2GHz Silver... Read more
12-inch 1.1GHz Gray Retina MacBook on sale fo...
B&H Photo has the 12″ 1.1GHz Gray Retina MacBook on sale for $1199 including free shipping plus NY sales tax only. Their price is $100 off MSRP, and it’s the lowest price available for this model... Read more
Apple now offering full line of Certified Ref...
Apple now has a full line of Certified Refurbished 2015 21″ & 27″ iMacs available for up to $350 off MSRP. Apple’s one-year warranty is standard, and shipping is free. The following models are... Read more
Free GUI Speedometer – The Ultimate Digital D...
Miami, Florida based RMKapps has announced the official release of GUI Speedometer 1.0, their digital dashboard display developed for iOS devices. GUI Speedometer allows users to track their precise... Read more
FutureCalc: Ergonomic iOS Calculator App For...
London, United Kingdom based Independent software developer and entrepreneur, Hovik Melikyan has announced the release and immediate availability of FutureCalc 1.0, his new ergonomic calculator app... Read more
Save up to $600 with Apple refurbished Mac Pr...
Apple has Certified Refurbished Mac Pros available for up to $600 off the cost of new models. An Apple one-year warranty is included with each Mac Pro, and shipping is free. The following... Read more

Jobs Board

*Apple* Subject Matter Expert - Experis (Uni...
This position is for an Apple Subject Matter Expert to assist in developing the architecture, support and services for integration of Apple devices into the domain. Read more
*Apple* Macintosh OSX - Net2Source Inc. (Uni...
…: * Work Authorization : * Contact Number(Best time to reach you) : Skills : Apple Macintosh OSX Location : New York, New York. Duartion : 6+ Months The associate would Read more
Computer Operations Technician ll - *Apple*...
# Web Announcement** Apple Technical Liaison**The George Mason University, Information Technology Services (ITS), Technology Support Services, Desktop Support Read more
Restaurant Manager - Apple Gilroy Inc./Apple...
…in every aspect of daily operation. WHY YOU'LL LIKE IT: You'll be the Big Apple . You'll solve problems. You'll get to show your ability to handle the stress and Read more
Simply Mac *Apple* Specialist- Service Repa...
Simply Mac is the largest premier retailer of Apple products in the nation. In order to support our growing customer base, we are currently looking for a driven Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.