gcode_analyze.py

import re
import numpy
import matplotlib.pyplot as plt
from PIL import Image, ImageDraw, ImageFont

####  Import gcode ###########################################

# Assume perfectly formatted gcode: 'g1x100.0y12.2'
def decode_command(val):
    return [float(i) for i in re.split(r'[gxy]\s*', val)[1:]]

with open('sample.gcode') as f:
    codes = [decode_command(line.rstrip()) for line in f]

    
####  Movement histogram ###########################################
    
# Create deltas
deltas = []
for a,b in zip(codes[0:-1], codes[1:]):
    dist = pow(pow(b[1] - a[1],2) + pow(b[2] - a[2],2),.5)
    deltas.append(dist)
    
    #print(a,b,dist)
    
#print(deltas)

plt.rcParams['figure.figsize'] = [12, 8]
plt.hist(deltas, 100, range=(0, 1))
plt.xlabel('Distance (units)')
plt.ylabel('Count')
plt.title('Histogram of movement sizes in sample gcode')
plt.show()


####  Remove any motions smaller than a threshold ###########################################

threshold = 1.5

new_pts = []
last_pt = codes[0]
for pt in codes[1:]:
    dist = pow(pow(pt[1] - last_pt[1],2) + pow(pt[2] - last_pt[2],2),.5)
    if(dist > threshold):
        new_pts.append(pt)
        last_pt = pt
        
print("Original length:{:}, reduced length:{:}".format(len(codes),len(new_pts)))
        
####  Draw the original and reduced images ###########################################
    
xmin = 0
xmax = 0
ymin = 0
ymax = 0

for code in codes:
    xmin = min(xmin, code[1])
    xmax = max(xmax, code[1])
    ymin = min(ymin, code[2])
    ymax = max(ymax, code[2])

scale = 5
im = Image.new('RGB', (scale*int(xmax)*2, scale*int(ymax)), (0, 0, 0, 0)) 
draw = ImageDraw.Draw(im)

# Plot original
draw.text((10,10), "Original ({:} points)".format(len(codes)), fill=(255,255,255,128))

c = 0
for a,b in zip(codes[0:-1], codes[1:]):
    if c == 0:
        fill=(255,0,0)
    else:
        fill=(0,255,0)
    c = (c+1) %2
    draw.line((scale*a[1],scale*a[2], scale*b[1],scale*b[2]), fill=fill)

# And reduced
draw.text((scale*int(xmax)+10,10), "Reduced ({:} points)".format(len(new_pts)), fill=(255,255,255,128))

for a,b in zip(new_pts[0:-1], new_pts[1:]):
    if c == 0:
        fill=(255,0,0)
    else:
        fill=(0,255,0)
    c = (c+1) %2
    draw.line((scale*int(xmax)+scale*a[1],scale*a[2], scale*int(xmax)+scale*b[1],scale*b[2]), fill=fill)
    
im.save('test.png')
    
display(im)