conformal.py

   1 #!/usr/bin/env python
   2
   3 #   Gimp-Python - allows the writing of Gimp plugins in Python.
   4 #   Copyright (C) 1997  James Henstridge <james@daa.com.au>
   5 #
   6 #    This program is free software; you can redistribute it and/or modify
   7 #   it under the terms of the GNU General Public License as published by
   8 #   the Free Software Foundation; either version 2 of the License, or
   9 #   (at your option) any later version.
  10 #
  11 #   This program is distributed in the hope that it will be useful,
  12 #   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 #   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 #   GNU General Public License for more details.
  15 #
  16 #   You should have received a copy of the GNU General Public License
  17 #   along with this program; if not, write to the Free Software
  18 #   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20 import math, cmath
  21 from math import *
  22 from cmath import *
  23 # allow access through module and without
  24 from array import array
  25 from gimpfu import *
  26 try:
  27         from fpconst import *
  28         import scipy.special
  29 except ImportError:
  30         pass
  31
  32 #import psyco
  33 #psyco.full()
  34
  35 def python_conformal(image, indrawable, code, xl, xr, yt, yb, grid):
  36         width = image.width
  37         height = image.height
  38         drawables = [ gimp.Layer(image, "Argument", width, height, RGBA_IMAGE, 100, NORMAL_MODE),
  39                       gimp.Layer(image, "Log. modulus", width, height, RGBA_IMAGE, 35, DARKEN_ONLY_MODE),
  40                       gimp.Layer(image, "Grid", width, height, RGBA_IMAGE, 10, DARKEN_ONLY_MODE)]
  41         image.disable_undo()
  42         l = 1
  43         for drawable in drawables:
  44                 image.add_layer(drawable, l)
  45                 l = -1
  46         image.remove_layer(indrawable)
  47
  48         bpp = drawables[0].bpp
  49
  50         gimp.tile_cache_ntiles(2 * (width + 63) / 64)
  51
  52         dest_rgns = [ drawable.get_pixel_rgn(0, 0, width, height, True, False) for drawable in drawables ]
  53         gradient = gimp.context_get_gradient()
  54         progress = 0
  55         max_progress = width * height
  56         gimp.progress_init("Conformally Mapping...")
  57         sx = (width-1.0)/(xr-xl)
  58         sy = (height-1.0)/(yt-yb)
  59         w = complex(0.0)
  60         z = complex(0.0)
  61         cx, cy = 0, 0
  62         ml2 = 2.0*math.log(2) # no need to do this 500*500 times...
  63         compiled=compile(code, "compiled code", "exec", 0, 1)
  64
  65         for row in range(0, height):
  66                 args = ()
  67                 mods = ()
  68                 sqrs = ()
  69                 for col in range(0, width):
  70                         z = col/sx + xl + 1j*( yt - row/sy)
  71                         exec(compiled)
  72                         arg = math.atan2(w.imag, w.real)
  73                         if arg<0.0:
  74                                 arg = arg + 2*math.pi
  75                         args = args + ( arg/(2*math.pi) ,)
  76                         try:
  77                                 mod = ( math.log(w.imag**2+w.real**2)/ml2 ) % 1.0
  78                         except OverflowError:
  79                                 mod=0.0
  80                         mods = mods + ( mod ,)
  81                         sqrs = sqrs + (bpp-1)*( 255*(((int)(w.imag/grid % 2.0) + (int)(w.real/grid % 2.0)) % 2) ,) + (255, )
  82
  83                 samples = gimp.gradient_get_custom_samples(gradient, args)
  84                 top_p = array("B", [ ((int)(255*samples[col][i]+0.5)) for col in range(0, width) for i in range(bpp) ] )
  85
  86                 dest_rgns[0][0:width, row] = top_p.tostring()
  87
  88                 samples = gimp.gradient_get_custom_samples("Default", mods)
  89                 top_p = array("B", [ ((int)(255*samples[col][i]+0.5)) for col in range(0, width) for i in range(bpp) ] )
  90                 dest_rgns[1][0:width, row] = top_p.tostring()
  91
  92                 top_p = array("B", sqrs )
  93                 dest_rgns[2][0:width, row] = top_p.tostring()
  94
  95                 progress = progress + width
  96                 gimp.progress_update(float(progress) / max_progress)
  97
  98         for drawable in drawables:
  99                 drawable.flush()
 100                 drawable.update(0,0,width,height)
 101         pdb.plug_in_edge(image,drawables[2], 10, 0, 0) # amount, WRAP, SOBEL
 102         pdb.plug_in_vinvert(image,drawables[2])
 103
 104         image.enable_undo()
 105
 106
 107
 108 register(
 109         "python_fu_conformal",
 110         "Colour representation of a conformal map",
 111         "Colour representation of a conformal map",
 112         "Michael J Gruber",
 113         "Michael J Gruber",
 114         "2005",
 115         "<Image>/Filters/Render/_Conformal ...",
 116         "RGB*, GRAY*, INDEXED*",
 117         [
 118                 (PF_TEXT, "code", "code", "w=z"),
 119                 (PF_FLOAT, "xl", "x left", -1.0),
 120                 (PF_FLOAT, "xr", "x right", 1.0),
 121                 (PF_FLOAT, "yt", "y top", 1.0),
 122                 (PF_FLOAT, "yb", "y bottom", -1.0),
 123                 (PF_FLOAT, "grid", "grid", 1.0),
 124         ],
 125         [],
 126         python_conformal)
 127
 128 main()