pathname.draw() VS drawpath(pathname)

Hello,

what's the difference - under the hood - between

pathname.draw()

drawpath(pathname)

Hi Giorgio,

They should behave the same. Can you provide an example where they don't?

Hello Tom,

sure! here's the example from the draft of some graphic work,
take a look at the final effect as it should be:
www.todo.to.it/clients/nodebox/lines_joydivision_ok.jpg
this was drawn with "drawpath(pathname)".

This one instead was drawn with "pathname.draw()"
www.todo.to.it/clients/nodebox/lines_joydivision_bizarre.jpg
(it would be nice to post images also in comments :-)

here's the code:

size(400,400)
background(0.5) # this is set to grey only to debug, it should be black
nofill()
nostroke()
 
core = ximport("coreimage")
 
canvas = core.canvas(150,150)
imm = canvas.layer("yourgrayscaleimage.png")
imm_w, imm_h = imm.size()
imm_w = int(imm_w)
imm_h = int(imm_h)
imm_p = imm.pixels()
step_x = 3
step_y = 10
linedepth = 70
 
def ovo(x,y,d):
    r = d/2.0
    oval(x-r,y-r,d,d)
    
strokewidth(0.6)
stroke(1)
fill(0)
 
colormode(RGB,255)
 
pathlist = []
 
for y in range(0, imm_h, step_y):
    multipath = BezierPath()
    multipath.moveto(0, y + linedepth)
 
    for x in range(0, imm_w, step_x):
        r, g, b = imm_p.get_pixel(x, y)
        c = color(r, g ,b)
        b = c.brightness
        multipath.lineto( x, y + b*linedepth)
        
    pathlist.append(multipath)
 
for i in range(len(pathlist)):
    pathlist[i].draw() # THE WEIRD ONE
    #drawpath(pathlist[i]) # THE OK ONE

Ah yes, I see. You should always use drawpath().
path.draw() is for internal use only - it draws the path without taking into account the current state.

If you must use path.draw(), then first intherit the state:

p.inheritFromContext()
p.draw()

Naturally, you could also do the grayscaling and blurring in the script itself:

imm.desaturate()
imm.filter_blur(5)

p = imm_p.get_pixel(x, y)
if len(p) == 4:
    r, g, b, a = p
else:
    r, g, b = p

Awesome! thanks for the useful tips.
If you like the idea of adding it to the gallery I'll be more than glad to prepare a document with proper images and a detailed description.

Please go ahead, we will be more than happy to add it, and thanks for sharing.