Simple ReadMe for SChopper 0.10
------------------------------

PLEASE NOTE VERSION NUMBER!
I am *certain* that there are still bugs in this code! ;-)

PLEASE NOTE NAME CHANGE!
Formerly just !Chopper which I've discovered clashes with a program by David Holden for chopping up large files to fit on floppy disc.

Thanks to SG for the new program icon.
(feel like doing one for MakeTable?) ;-)


Contact: rdavison@xtra.co.nz


SChopper is a little tool that lets you divide an image up into rectangular
sections which can then be saved as a number of separate images.

This can be useful for website design.

SChopper can function standalone or as a PCA (Plugin-Compliant-Application) tool.

Standalone - Give SChopper a sprite to work on by dragging the sprite to it.
NB. Saving from another app. is untested and probably won't work. ;-)
    Only the first sprite in a sprite file is used.
    It may not work with 'non-square' aspect ratio (or other weird) sprites.

PCA - Hook SChopper up to a sprite in a PCA compliant application using the PCA
protocol. See my website for if you don't know what PCA is and want to find out.


Use
---

Hokay, you have an image in a window with a small tool pane attached to the
left hand side.

The tools are (from top to bottom, left to right)

Select mode
Horizontal line (default)
Save
Vertical line


When Horizontal line is selected

Clicking select adds a horizontal 'cut' to the image
 - adjust will give you a vertical 'cut'

When Vertical line is selected

Clicking select adds a vertical 'cut' to the image
 - adjust gives you a horizontal...

When Arrow is selected

Clicking on a line selects it (colour changes)
- then dragging the line moves it
- Ctrl-X deletes it
(when in select mode you can add lines by double clicking but this feature is
depreciated ;-)

NB. You currently can only select one line at a time. ;-)

Menu gives you a menu (but, as a RISC OS user you probably knew that)


Save  -> Sections ->

Drag the directory icon to disc to cut the image up into sections. A directory
will be created at the destination location and the image will be divided up
using the leaf name you provide, appending '01', '02' etc. as appropriate.
Rectangles start from top left and run to bottom right.

Before saving you can select between sprite, jpeg, gif and png output files.
Please note that GIF output requires you to have Intergif by Peter Hartley and similarly PNG save needs you to have !Spr2Png by Darren Salt.

If you do not have these programs can I suggest you go and get them?

InterGif : http://utter.chaos.org.uk/~pdh/software/intergif.htm
Spr2Png  : http://www.youmustbejoking.demon.co.uk/progs.html#spr2png


If the original image has a mask then the program attempts to divide
this up and add it to the appropriate sections. Note that this
requires some more free memory. I say attempts because there seems to
be some sort of minor bug in the OS mask plotting routines that cause
it to never plot the top line of the mask.

(SChopper works works by giving each newly created section a blank
mask then switching output into it (the mask) and plotting the
original full sprites mask at an appropriate offset - the dimensions
of the section act as a clipping rectangle so the right bits of the
mask get made solid).

Solution: Don't use masked sprites which have solid pixels in the top
line. :-)


Note: JPEG output degrades image quality (inherent effect of the JPEG
compression algorithm). Also, JPEG doesn't support proper masking.
If you turn on the 'False-mask' option then image sections masked out
will be filled to the supplied background colour - this gives the
impression of simple masking if the background is a flat colour.



Tidy > Horizontal
       Vertical

This attempts to divide the image up into equal sections by moving the lines so
they are an even distance apart. Obviously, if the image doesn't divide up
neatly some of the rectangles will end up bigger than others.

Tidy > Grid X
       Grid Y

These move lines to the nearest grid positions (regardless of the grid state)


Options

Opens an options window. Currently Grid settings, JPEG, GIF and PNG options. Hopefully most of them should be self-explanatory.

Note that all of my down/up 'bump arrows' respond to Shift and Ctrl key modifiers to change the value more rapidly.


Eg. (from cold)

Load an image
Click twice over the image (anywhere)
Choose the vertical line tool
Click three times over the image (anywhere)
MENU, Tidy->Horizontal (with ADJUST), then Tidy->Vertical
Save this and have a look at the resulting sprites.



Thats it. Hope it is useful to you.

