Gunter Bachelier on wrote...
| Dear Anthony Thyssen,
|
| > Use gravity...
| > convert p3m1_G2b.png -gravity East -crop
1501x1300+0+0 p3m1_G2.png
|
| I have tried this but -gravity East cuts something at the
top of the
| image, it works with -gravity NorthEast (there might be an
additional
| problem with the geometry values, see below).
|
|
Sorry yes you will want North East to place your crop
relative to the
top right corner.
| > convert -size 2250x1300 xc:
| > -page -750+0 p3m1_G6.png
| > -page +0+0 p3m1_G1.png
| > -page +750+0 p3m1_G2.png
| > -page +1500+0 p3m1_G5.png
| > -flatten p3m1_tile_part.png
| >
| > I get the right result (after I fixed the +repage
after crops).
|
| the good news is: it works in principle and it is very (!)
fast:
|
| http://www.vi-anec.de
/Trance-Art/IM-examples/IM-plane_group_p3m1/p3m1_tile_part_f
latten.png
| (10 MB)
|
| the bad news is: with the given geometry values it has
(white) pixel
| artifacts at the edges where the images come together
(even at the
| bottom - top??). The seamlessness is the crucial
attribute therefore
| no compromise can be done here.
| The tile_part that was generated with my original sequence
has
| a width of 2252 where this tile_part has the predefined
width of 2250.
| The artifacts can be seen after the tile is generated from
the tile_part:
|
| http://www.vi-anec.de/Tra
nce-Art/IM-examples/IM-plane_group_p3m1/p3m1_tile_flatten2.p
ng
| (40 MB)
|
File not found. But I understand your point.
It mat be that you will need to adjust the image diagonals
to overlay
correctly.The colors of the pixels along the two adjoining
images should
match up, so a slight one pixel overlap should not be
noticable.
Looking at the first image a full scale view shows a very
light diagonal
join line.
| I will experiment with some other x-geometry (-749 or -751
instead -750)
| but why there are artifacts in the middle of
p3m1_tile_flatten2.png
| where the y-geometry is always 0 is unknown to me.
xc: by default craetes a white background. On solution may
be to
use xc:none (transparent color) then use a +matte afetr
the flatten to
make all semi-transparent pixels fully opaque. that means
partical
overlaps will be handled, however if any pixel did not get
any coverage
then that pixel will become black (none = fully transparent
black).
I shrunk the canvas size slightly so that the images would
overlap slightly so
as to ensure no partical overlaping occurs. The result
while not
mathematically correct should not have any gross errors. It
will also still tile fine, though produce a slightly smaller
image.
| The only reason I can think of is that one or more of the
intermediate images
| p3m1_G1.png, p3m1_G2.png, p3m1_G5.png and p3m1_G6.png are
invalide.
I couldn't see the image to comment!
| In this example I used p3m1_G2.png generated by the larger
rotated
| image p3m1_G2b.png with the crop command
| convert p3m1_G2b.png -gravity NorthEast -crop
1501x1300+0+0 p3m1_G2.png
| If here the y-geometry is 1-2 pixel wrong this could
explain the
| horizontal artifacts.
|
It is more likely that a rotate of 60 degrees, expanded the
image by one
pixel too much, In that case your original mathematically
derived offset
will be a better idea.
Also your equalateral triangle may not be exactly equlateral
as you are
using integers for your specification. IM does handle
floating point, and
it may be some adjustments is needed to get the edge pixels
right.
Perhaps a some experiments with a smaller solid color
triangles of
different colors, will be better to check on how well the
images match
up at the pixel level.
| Apart from this geometry issue the problem with this
one-line IM command
| is that I don't know yet how to translate it in
PerlMagick.
| The literature I have (Lehmann, M.: Programmieren von
Grafiken mit Perl. 2003)
| has no examples for the use of -page and -flatten
| (is -page a method or an attribute used by what method?)
|
The IM website gives a list of all the perlMagick option
available.
though how complete it is is another matter.
| > This tile is then just mirror tiled...
| >
| > convert p3m1_tile_part.png
| > ( +clone -flop ) +append
| > ( +clone -flip ) -append p3m1_tile.png
|
| This is the generation sequence that is used in pmm and
| p4m. p3m1 has a sequence that differs in one point:
| there is flip in the two brackets. If flop and flip is
| used the result (with the flatten version) is
|
The parenthesis start a new image sequence seperate to the
original.
A clone (or copy) is made and flopped or flipped, and the
result then
appeads to the original image sequence, for appending.
The alturnative is to flip images to temporary files as you
previouslay
did
See IM examples basics, parenthesis
http://www.cit.gu.edu.au/~anthony/graphics/
imagick6/basics/#image_seq
| http://www.vi-anec.de/Tra
nce-Art/IM-examples/IM-plane_group_p3m1/p3m1_tile_flatten1.p
ng
| (40 MB)
|
| In contrast the sequence
| convert p3m1_tile_part.png
| ( +clone -flip ) +append
| ( +clone -flip ) -append p3m1_tile.png
|
| delivers the right tile (with the non flatten version)
| http://www.vi-anec.de/Trance-Art/I
M-examples/IM-plane_group_p3m1/p3m1_tile.png
| (40 MB)
|
Not sure that the colors would line up with a vertical flip
before a
horizontal append!!!
Anthony Thyssen ( System Programmer ) <A.Thyssen griffith.edu.au>
-----------------------------------------------------------
------------------
Anyone who slaps a 'This page is best viewed with Browser
X' label
on a Web page appears to be yearning for the bad old days,
before
the Web, when you had very little chance of reading a
document written
on another computer, another word processor, or another
network.
-- Tim
Berners-Lee, 1996
-----------------------------------------------------------
------------------
Anthony's Home is his Castle http://www.cit.gu.
edu.au/~anthony/
_______________________________________________
Magick-users mailing list
Magick-usersimagemagick.org
http://studio.imagemagick.org/mailman/listinfo/magick
-users
|
