Working in Inches

[bidgeeman]

Hi.
I can't find anything on the forum relating to this question.

How would you go about making an image area that can be resized by
allowing a user to write in inches and fractions of inches into a text area?

Bidge

[richmond62]

Well the first thing you'll have to worry about is a conversion routine from inches to points,
after that everything should be remarkably straightforward: well, always remembering that a 600 pixel wide stack on
my display when it is set at 640 x 480 looks far bigger inches-wise than when my display is set at 1920 x 1080.

[bidgeeman]

Hi richmond62.
What about people who use inches to measure something like in the US. How do they go about inputing a measurement in inches?
I tried adding 3 1/3 + 1 1/2 of course LC didn't know what the hell was going on

Bidge

[richmond62]

Well . . .

1. I'm not American.

2. I don't like Napoleonic units so I'm fine with inches.

3. You can have inches and 'traditional' divisions of inches: quarter, half, three-quarters

or you could be a "bit metric" and divide your inches up into 10 subunits (much easier).

If you want to "fool around" with quarters and so forth the first thing you're going to need to do is use proper symbols for the
fractions rather than 'one slash three' . . .

http://www.unicode.org/charts/PDF/U0080.pdf

Unicode addresses: quarter BC , half BD , three-quarters BE

[bidgeeman]

Hi richmond62.
That's very handy to know thanks

Bidge

[richmond62]

Bl**dy silly really:

[richmond62]

This Unicode table gives you loads more vulgar fractions:

http://www.unicode.org/charts/PDF/U2150.pdf

[bidgeeman]

You would think it would make more sense to type in a decimal rather than a fraction?
Very nice stack though
Bidge

[richmond62]

Nutty Fruitcakes . . .

INCHER.livecode.zip

Here's the stack

(2.52 KiB) Downloaded 189 times

[richmond62]

You would think it would make more sense to type in a decimal rather than a fraction?

Well, frankly, I'll always go for "two slash three" rather than .666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666666

[bidgeeman]

That's right...always looking for the easy solution

Bidge

[dunbarx]

So, bidgeeman, the banter aside, are you clear and comfortable about pixels, inches and screen resolution?.

Craig Newman

[bidgeeman]

Hi Craig.
Yes thank you almost If I have any more problems I will post here. Thank you so much for asking

Bidge

[bidgeeman]

This is driving me nuts mainly because my math is not my strength.

I am trying to convert ruler measurements to onscreen positions
for people who need to print pre-cut labels on an A4 sheet accurately
by measuring the sheet cut positions with a ruler and filling out 6 fields.
Side, Top, Side gap and Base gap, Label width, Label Height.

This works perfectly with millimeters using this equation:
(mm) =595(screen pixel width) x 25.4 (amount of mm in an inch) / 72 (dpi)
Answer: 209.9027 (rounded off)
Divide this by 595(screen pixels) and you get:
0.3527(rounded off)
0.3527 is equivalent on screen to 1mm on a ruler which is easy to read and write
as there are 10 millimeters to 1 cm.

The problem is trying to convert this all to inches!
1 inch is divided into 16 and I need 1 x field where you can type the inch value and
another field for the 16/th value, then add them together but I can't get it to work when I
add the two fields together.
I'm guessing problem is that inches are divided into 16 so to get a conversion value that works,
the width, 595, has to be split into 16ths?
I just don't know how to arrive at the correct pixel value for a 16th of an inch at 595 pixels at 72 dpi?


I hope I have explained this correctly.
Can anyone help?
Thanks
Bidge

[bogs]

bidge, I hope this helps you out a bit. I am by no means a strong math type either, so I cheat a LOT ! Since I see from your examples that your "rounding off" a few times, perhaps that chart will be of some use.

As far as what an inch can be divided into, the possibilities are endless. When I worked in a machine shop, we worked to thousandths of an inch. Later a great deal of shops switched over to metric, or used both. Most standard rulers are divided into 16ths of an inch, as you point out. A great number are (depending on your field) going to be in 32nds or even 64ths.

Another way you could tackle it is to take your own figures. If 25.4 is the number of millimeters in an inch, and you already have a working formula for mm measuring, use that to come to your inch measurements, i.e. 25.4 / 16 would give you the number of mm in 1/16th of an inch, then you plug that into your formula. In one way this is easier, but more complicated, and it certainly is one way you can tackle it.

Yet a 3rd way to figure out what you need to know might be using a photo-editing program, like gimp or photoshop or a gazillion others. I know that most have a scaling section, where you can scale according to pixels, %'s, inches, etc. If you have a picture of whatever size, you can scale it using 1/16th of an inch, then hit scale again to see what it is in pixels at that point. While this is more work, it would certainly give you the number of pixels in 1/16th of an inch at any number of dpi.

As I said, I hope this helps you a bit.