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#!/usr/bin/env python3
# Copyright (C) 2010 Simon Wood
# Copyright (C) 2010 Hazen Babcock
# Copyright (C) 2010-2016 Alan W. Irwin
# Simple amalgamated demo of plsmem and plsmema under Python for the
# mem, memcairo, and memqt devices.
#
# This file is part of PLplot.
#
# PLplot is free software; you can redistribute it and/or modify
# it under the terms of the GNU Library General Public License as published
# by the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# PLplot is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Library General Public License for more details.
#
# You should have received a copy of the GNU Library General Public License
# along with PLplot; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#
from PIL import Image
import math
import numpy.numarray
from plplot_python_start import *
import plplot as w
def plot(w, device_name, ifRGBA, width, height, my_buffer, x, y, data, max_val):
if ifRGBA:
colour_code = "RGBA"
# initialise for mem-style RGBA device
w.plsmema(width,height,my_buffer)
else:
colour_code = "RGB"
# initialise for mem-style RGB device
w.plsmem(width,height,my_buffer)
w.plstart (device_name, 1, 1);
w.plcol0(2)
w.plenv(0, 360, 0, 90, 0, 2)
w.plcol0(2)
w.pllab("Azimuth", "Elevation", "Rectangular Sky View with " + colour_code + " " + device_name + " device")
# plot binned density
w.plimage(data, 0, 360, 0, 90, 0, max_val, 0, 360, 0, 90)
# plot points
w.plpoin(x,y,5)
# have to finish plotting so that the plot data gets transferred
# back from the cairo working surface to the user supplied memory.
w.plend1()
# Use fromstring as frombuffer will invert the image
my_image = Image.fromstring(colour_code, (width,height), my_buffer)
my_image.save(device_name + "_" + colour_code + ".png")
# ---------------------------------------------------
# Build random array (aka fake data)
w.plseed(1234)
x=[]
y=[]
for i in range(500) :
x.append(w.plrandd() * 360)
y.append(w.plrandd() * 90)
# compute binned density on 15' boundaries
# 360' gives 24 divisions
# 90' gives 6 divisions
width = 24
height = 6
max_val = 0
data = numpy.numarray.zeros((width,height))
for i in range(len(x)):
data[int(x[i]/(360/width))][int(y[i]/(90/height))] += 1
if data[int(x[i]/(360/width))][int(y[i]/(90/height))] > max_val:
max_val +=1
# ---------------------------------------------------
# Initialise buffer
# Start from a blank canvas
width = 480
height = 320
# Dark gray background (necessarily opaque for RGB format).
background = numpy.numarray.zeros(3, numpy.uint8) + 30
my_buffer = numpy.numarray.zeros((height,width,3), numpy.uint8) + background
# Dark gray semi-transparent background.
background = numpy.numarray.zeros(4, numpy.uint8) + 30
background[3] = 200
my_buffera = numpy.numarray.zeros((height,width,4), numpy.uint8) + background
'''
# Or open an existing image
# (note 'asarray' will fail as it sees PIL image as an array already and
# does not perform a copy to make a writable array)
src_img = Image.open("input.png")
my_buffer = numpy.array(src_img.convert('RGB'), numpy.uint8)
(width, height) = src_img.size
'''
# Configured device_list depends on what w.plsmem and w.plsmema devices
# are available from the PLplot build.
device_list = @PLSMEM_DEVICE_LIST@
for device_name in device_list:
# plot writes on top of buffer each time so must use an independent (deep) copy.
buffer = numpy.array(my_buffer,copy=True)
plot(w, device_name, False, width, height, buffer, x, y, data, max_val)
# "mem" device does not (yet) have RGBA capability.
if device_name != "mem":
buffer = numpy.array(my_buffera,copy=True)
plot(w, device_name, True, width, height, buffer, x, y, data, max_val)
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