Monday, July 16, 2012

pstops tutorial (psutils)

I have recently started to port my game engine GGE to HTML5. So i downloaded javascript & HTML5 tutorials (PDFs) from http://www.tutorialspoint.com/.


But now a days i only keep pocket references for technologies i use instead of heavy books. So i wanted to make a pocket version of those PDFs. I found "pstops" after google'ing, in just an hour i was irritated by the mangled parameters it needed and badly documented manpages & stuffs on internet.


But these two pages made my concept clear and i achieved my task in few minutes.


[REF1] Read this first:
http://wiki.scribus.net/canvas/How_to_make_impositions_with_pstops

[REF2] Then ( this will make you clear about what exactly pstops does):
http://code.google.com/p/uwisdom/wiki/Pstops

My own description ( i assume you have read REF1):
pstops => postscript to postscript converter with desired arrangements, page layouts and sizes.

I will describe this powerful utility by small implementation because that in run accomplishes many people's job.

For experiments please get a ps file of atleast 16 pages. You can convert a PDF into ps by using pdftops utility (its a part of psutils). I am using 23 page file. Lets do some ps conversions.


1. Flip all the pages vertically Or horizontally
vertically:
pstops '1:0V' in.ps out.ps 



Horizontally:
pstops '1:0H' in.ps out.ps 



Description:
As you can see the parameters of pstops are:

pstops  [ -q ] [ -b ] [ -wwidth ] [ -hheight ] [ -ppaper ] [ -dlwidth ] pagespecs [ infile [ outfile ] ]


Most of us have difficulty in pagespecs parameter only. Which is described below:

pagespecs   = [modulo:]specs
specs          = spec[+specs][,specs]
spec            = [-]pageno[L][R][U][H][V][@scale][(xoff,yoff)]

In our flip example, we used '1:0H', What are these hex like codes? lets dissect -
1 => it tells that we want  to print 1 page of "in.ps" in 1 page of out.ps (A4 by default).
If we want to print 4 pages in 1 A4 page we have to use '4:0', for 8 we use '8:0'

:0  
: sign is followed by SPECS. But we have nothing after 0. It simply means that we want to use original unchanged source pages in output file. With -0 end becomes start and start becomes end page. i.e. page numbers get inverted.

2. Lets print two pages in one side, i.e. total 4 in 1 output page. Portrait mode 
pstops '4:0' in.ps out.ps
output => [1] [2] [3] [4] [5] [6] Wrote 6 pages, 1250990 bytes

We get 6 pages in output. But, upon seeing out.ps why we get only 6 pages printed from source instead of all pages? The answer is simple: Did we specified how and where the pages had to be printed? we told to print 0 only i.e. 1st page ( 0 index => 0+1 page number ) of every block.

You don't know what block is? Please refer to REF1 above. In brief i also write here:
Blocks = total pages in input file / total pages we want in our 1 page of output file

1 block simply means number of input pages we want to be printed in 1 output page, above we told to print only 0th index Or 1st page of every block. That is why only 1st pages were printed.

Below is the proper command to print all pages.
pstops '4:0@0.5(0.0w,0.5h)+2@0.5(0.0w,0.0h),1@0.5(0.0w,0.5h)+3@0.5(0.0w,0.0h)' in.ps out.ps

It will output 2 portrait pages per side. Lets understand all the parameters:
4: => 4 input pages / 1 output page

0@0.5(0.0w,0.5h) 
0 => 0th index of block i.e. 1st page
(0.0w,0.5h) => move right by 0% of page width. 50% of height. AFAIK the w,h are of source page.
@0.5 => scale to become 50% of original size.

+2@0.5(0.0w,0.0h)
+ => continuing page on 1st side.
2 => 2nd index of block i.e. 3rd page
(0.0w,0.0h) => no movement, just remain at output's Origin i.e. left-bottom. Just like Cartesian coordinates.
@0.5 => scale to become 50% of original size.

NOTE:
1. x,y are offsets, this is what i have understood, they are not exact render start points. Therefore you should have noticed to draw from top we just have to go 0.5h ( half of output page height instead of full height). 

2. I have not used rotations. You should keep in mind that after rotation the origin of that rotated page still remains at its own left-bottom. So the whole output will change after using rotations. Try it:

pstops '4:0L@0.5(0.0w,0.5h)+2L@0.5(0.0w,0.0h),1L@0.5(0.0w,0.5h)+3L@0.5(0.0w,0.0h)' in.ps out.ps

It outputs blank pages! You know why?
Because when we rotated left (imagine you are holding the paper at left-bottom and rotated it left. Then it goes outside of the output page boundaries. For that you have to translate all pages by full width.

so try this now:

pstops '4:0L@0.5(0.75w,0.5h)+2L@0.5(0.75w,0.0h),1L@0.5(0.75w,0.5h)+3L@0.5(0.75w,0.0h)' in.ps out.ps

in parameters we have described that 1st side of output page will follow this specification:
pages: 1, 3
0L@0.5(0.75w,0.5h)+2L@0.5(0.75w,0.0h)
and the second back side will follow this: ( separated by comma )
pages: 2, 4
1L@0.5(0.75w,0.5h)+3L@0.5(0.75w,0.0h)

Then all the coming blocks will follow these specifications.


For more details below is a simple illustration: please neglect the quality, i made it quickly to illustrate rather than writing 100 lines. :-)
























hope this tutorial will help you to understand how to utilize the power of pstops without Hit n Trials method :-p. Please let me know if you find some bugs or wrong info (if really it is).


Search TAGs:
linux 4-up, make 8 page booklet, linux pstops tutorial, pstops concept, how pstops works, make mini booklets, 8 page booklets 

Saturday, April 28, 2012

Gimp Script for exporting positions of all the layers.

Gimp Script for exporting positions of all the layers.


I have created a Python script which can export layer positions in a text file.

Usability:
Are you using GIMP for creating maps for your game? You want to create a 1024x768 map and put objects in it but cannot export the positions? This script can help you get the positions of your objects.

Procedure:
  1. Run GIMP and create a desired resolution image.
  2. Drag and add your object's images in gimp.
  3. Ensure that you crop the layers so that extra alpha (transparent) areas are not remained in objects.
  4. Duplicate the objects to the numbers you want and place them to positions you want.
  5.  Do same with other objects, backgrounds.
  6. Now export their positions. Filters -> Positioning -> Layers Position Dumper
  7. Put the file name with full path in next dialog. e.g. ~/my_game_map.txt in Linux Or c:\my_game_map.txt in windows. Click Ok.
  8. Now you can check the exported file which contains the positions of all the layers.

How to install the plug-in?
Firstly ensure that you have Python installed in your system. Try to install gimp until you see option of "GIMP python plugin" options checked while installation.

If you haven't installed it please install these packages, This is my installer package: gimp-2.6.11-i686-setup, python-2.5.2.msi

However you can download individual packages by google
gtk-2.12.9-win32-1.exe, pycairo-1.4.12-1.win32-py2.5.exe, pygobject-2.14.1-1.win32-py2.5.exe, pygtk-2.12.1-2.win32-py2.5.exe, python-2.5.2.msi


Or follow this page:
http://www.gimpusers.com/tutorials/install-python-for-gimp-2-6-windows


Install the plugin
Copy the python script to:
WIndows: C:\Documents and Settings\USER\.gimp-2.6\plug-ins
Linux: ~/.gimp-2.6/plug-ins
and restart gimp.

Verify that you have gimp python plugins enabled by following these steps:
Filters -> Python-Fu -> Console

type this:
>>> import gimpfu
>>> gimp.version
(2, 6, 11)


Sample exported file:


Format RATIONAL:
"layer name" X%-Pos Y%-Pos %Width %Height

Format PIXEL:
"layer name" X-Pos Y-Pos Width Height

RATIONAL: "Frame 1.png" 0.000000 0.000000 26.756757 94.634146
PIXEL:    "Frame 1.png" 0.000000 0.000000 99.000000 194.000000

RATIONAL: "Frame 2.png" 26.756757 0.000000 18.918919 99.512195
PIXEL:    "Frame 2.png" 99.000000 0.000000 70.000000 204.000000

RATIONAL: "Frame 3.png" 45.675676 0.000000 25.675676 98.048780
PIXEL:    "Frame 3.png" 169.000000 0.000000 95.000000 201.000000

RATIONAL: "Frame 5.png" 71.351351 0.000000 28.108108 97.073171
PIXEL:    "Frame 5.png" 264.000000 0.000000 104.000000 199.000000

... more dump stripped off



Download:
layer-position-dumper.7z (GIMP v2.6 & 2.8 both )

Raw code:


#!/usr/bin/env python

from gimpfu import *

gettext.install("gimp20-python", gimp.locale_directory, unicode=True)

def layer_position_dumper(img, drawable, filename):
out = file( filename,"w")
out.write( 'Developed by Bindesh Kumar Singh on 26 April 2012\n')
out.write( 'This Plugin is a utility of Greh Game Engine (C) 2009-2012\n')
out.write( 'It dumps the positions of all the layers in a specified text file\n\n')
out.write( 'Format RATIONAL:\n"layer name" X%-Pos Y%-Pos %Width %Height\n\n' )
out.write( 'Format PIXEL:\n"layer name" X-Pos Y-Pos Width Height\n\n\n\n' )
count = 0
w = float( img.width )
h = float( img.height )
for l in img.layers:
if 1 == pdb.gimp_item_is_group( l ):
#print 'group hai'
for gl in l.layers:
x = float( gl.offsets[0] ) * 100.0
y = float( gl.offsets[1] ) * 100.0
lw = float( gl.width ) * 100.0
lh = float( gl.height ) * 100.0
out.write( 'RATIONAL: "%s" %f %f %f %f\n' % ( gl.name, x / w, y / h, lw / w, lh / h ) )
out.write( 'PIXEL:    "%s" %f %f %f %f\n\n' % ( gl.name, gl.offsets[0], gl.offsets[1], gl.width, gl.height ) )
count += 1
else:
#print 'group nahin hai'
x = float( l.offsets[0] ) * 100.0
y = float( l.offsets[1] ) * 100.0
lw = float( l.width ) * 100.0
lh = float( l.height ) * 100.0
out.write( 'RATIONAL: "%s" %f %f %f %f\n' % ( l.name, x / w, y / h, lw / w, lh / h ) )
out.write( 'PIXEL:    "%s" %f %f %f %f\n\n' % ( l.name, l.offsets[0], l.offsets[1], l.width, l.height ) )
count += 1
out.close()


register(
"layer_position_dumper",
"Dump positions of the layers",
"Dumps the offsets/positions of all the layer in a specified file",
"Bindesh Kumar Singh",
"Developed for GrehGameEngine",
"2012",
"_Layers Position Dumper",
"RGB*, GRAY*",
[(PF_IMAGE, "image",       "Input image", None), (PF_DRAWABLE, "drawable", "Input drawable", None), (PF_STRING, "name",       _("_File name with full path"), _("layer_positions.txt"))],
[],
layer_position_dumper,
menu="/Filters/Positioning",
domain=("gimp20-python", gimp.locale_directory)
)

main()



[ 2.8 is currently limited in recursions of groups inside groups. ]

Search tags:
gimp export layer positions, export positions of layers in gim, gimp layer position dumper plugin.

Tuesday, December 27, 2011

Use android device to connect to internet on PC using USB cable or any wireless source.

I was new to android, and wanted to connect to internet via GPRS/EDGE/3G connections. But unfortunately I couldn't find any modem support in android. In run of demand for a DUN connection I found tethering option in Android phone and found connecting to PC for internet via Android is dead easy!, thanks to tethering, below are the steps and references:-


My devices and setup:
Android version: v2.2, Froyo
Device: ZTE Blade (Or Dell XCD35, Idea Blade in India)
PC: Toshiba Satellite C650 AMD Athlon II P320 CPU, HD4200 ATI card
OS: Windows XP

STEPS:
1. Enable Internet on your Android phone via any source you have access to like GPRS/EDGE/3G data plans.
2. Connect the phone to your Laptop/desktop using USB cable (Otherwise below option will be disabled)
3. Go to phone settings and enable USB tethering :-

Press Home -> press menu -> wireless & networks -> Tethering & portable hotspot -> USB Tethering
Enable this check button.


Once enabled,  If your pc drivers are installed correctly, you will see HSUSB device connected message, remote NDIS adapter device will be shown on your device manager.


Verify the correct setup:
1. Check if your Android device shows BLUE USB icon on the taskbar which opens tethering upon touch event.
2. Open Device manager in windows XP or other OS. Network adapters should show

"Remote NDIS based internet sharing device"


My details are:
Manufacturer: ZTE Corporation
Location: Location 0 (ZTE HSUSB Device)
Control panel => Network Connections => Remote NDIS based internet sharing device




 4. Test internet on your phone if it works, then for sure you will get same speed in your PC.



You can test the speed of your internet by simple command. Open cmd.exe from run dialog and type

ping google.com

below is output from my console:

Pinging google.com [74.125.113.104] with 32 bytes of data:


Reply from 74.125.113.104: bytes=32 time=516ms TTL=45
Reply from 74.125.113.104: bytes=32 time=517ms TTL=45
Reply from 74.125.113.104: bytes=32 time=513ms TTL=45
Reply from 74.125.113.104: bytes=32 time=515ms TTL=45



The lower your time is the faster your internet connection will be. EDGE normally shows values between 200 to 700. Values above it are very slow connection. I get ~250 average in low traffic, ~20-30KBps.




CONCLUSION:
Android's USB tethering just means to share internet from your device to other device no matter what the source of your internet is. So we don't need any kind of Dial Up networking support in phones. So this is a universal solution and that's why android don't need DUN :-).




References:
Tethering & Hotspot
http://support.google.com/mobile/bin/answer.py?hl=en&answer=182134


Share your mobile data connection:
http://support.google.com/mobile/bin/answer.py?hl=en&answer=168932


Windows XP's Android RNDIS device information, tethering, INF file
http://www.android.com/drivers/tetherxp.inf



ZTE Blade drivers:
http://www.zte.co.jp/products/handsets/handsets_gallery/softbank/info/201012/P020101217594818380622.zip

ftp://ca:welcome@ftp.brightpointuk.co.uk/Technical%20Support/ZTE/ZTE_Handset_USB_Driver.exe


Plugging Android phone to PC shows a CDROM with their drivers which upon enabling SDCARD gets removed.



EXTRA (part of my marketing):

If above steps have solved your problem and you are happy, and you do not hate games :), please try the games I have developed.


DesiBallGame - My first android game, recently released

https://play.google.com/store/apps/details?id=org.greh.desiballgame


 My PlayStore profile:

https://play.google.com/store/apps/developer?id=GamesGreh


My website for games:

http://www.gamesgreh.in