# Help drawing recursive trees

**URL:** <https://discourse.processing.org/t/help-drawing-recursive-trees/34656>\
**Category:** Processing.py\
**Created:** [January 15, 2022, 11:21pm UTC](https://discourse.processing.org/t/help-drawing-recursive-trees/34656 "2022-01-15T23:21:50Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![43zombiegit](https://avatars.discourse-cdn.com/v4/letter/4/d78d45/32.png) [@43zombiegit](https://discourse.processing.org/u/43zombiegit)\
**Post date:** [January 15, 2022, 11:21pm UTC](https://discourse.processing.org/t/help-drawing-recursive-trees/34656/1 "2022-01-15T23:21:50Z")

</div>

Hi guys, I have the following code. I’m trying to get the branches to draw slowly through the draw function and not during one draw iteration but can’t figure it out given the recursion.

If anyone could help that would be great and if anyone knows how to edit this text to be in code that would be useful thanks!

import time

def setup():  
size(1000, 1000);  
background(0)  
stroke(83,53,10)

def draw():

# frameRate(1)

original\_size = 120  
translate(width/2,height)  
first\_branch\_size = 120  
left, right = get\_direction(probability = 0.5)  
first\_thickness\_size = 5  
strokeWeight(first\_thickness\_size)  
line(0,0,0,-original\_size);  
translate(0,-original\_size);

branch(first\_branch\_size, left, right, threshold = 30, first\_thickness\_size = first\_thickness\_size);

#multiple\_branch(first\_branch\_size, left, right, threshold = 30, first\_thickness\_size = first\_thickness\_size)

# time.sleep(5)

def get\_direction(probability = 0.1):  
random\_int = random(0,1)

```
left_probability = 1 - probability
left, right = False, False
if random_int >= left_probability:
    left = True
elif random_int <= probability:
    left = True
else:
    left, right = True, True

return left, right

```

def draw\_branch(theta, h, threshold, first\_thickness\_size):  
first\_thickness\_size \*= random(0.6, 0.9)  
strokeWeight(first\_thickness\_size)  
pushMatrix();  
rotate(-theta);  
line(0, 0, 0, -h);  
# for i in range(100):  
# y = lerp(0, 0, i/100)  
# point(0, y)  
translate(0, -h);  
left, right = get\_direction()  
branch(h, left, right, threshold, first\_thickness\_size);  
popMatrix();

def branch(h, left, right, threshold = 6, first\_thickness\_size = 3):

a = random(-30, 30)  
steps = 10  
theta = radians(a)

h \*= random(0.7, 1);  
if (h \> threshold):  
if right:  
draw\_branch(theta, h, threshold, first\_thickness\_size) # Whenever we get back here, we “pop” in order to restore the previous matrix state  
if left:  
draw\_branch(-theta, h, threshold, first\_thickness\_size)  
# Repeat the same thing, only branch off to the “left” this time!

else:  
lights();  
pushMatrix()  
fill(random(30,45), random(45,90), random(1,39))  
ellipse(0, 0, random(1,5), random(1,20))

```
  translate(0,-h)
  popMatrix()

```

def multiple\_branch(first\_branch\_size, left, right, threshold, first\_thickness\_size = 10):  
branch(first\_branch\_size, left, right, threshold = 30, first\_thickness\_size = first\_thickness\_size);  
branch(first\_branch\_size, left, right, threshold = 20, first\_thickness\_size = first\_thickness\_size);  
branch(first\_branch\_size, left, right, threshold = 10, first\_thickness\_size = first\_thickness\_size);

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<div class="post-metadata">

**Author:** ![mnse](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/mnse/32/16520_2.png) [@mnse](https://discourse.processing.org/u/mnse)\
**Post date:** [January 6, 2023, 6:55am UTC](https://discourse.processing.org/t/help-drawing-recursive-trees/34656/2 "2023-01-06T06:55:58Z")

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Hi @43zombiegit,

Please help us to help you and follow instructions here to format your code.

[https://discourse.processing.org/faq#format-your-code](https://discourse.processing.org/faq#format-your-code)

Cheers  
— mnse

---

<div class="post-metadata">

**Author:** ![tabreturn](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/tabreturn/32/3697_2.png) [@tabreturn](https://discourse.processing.org/u/tabreturn)\
**Post date:** [January 6, 2023, 8:12am UTC](https://discourse.processing.org/t/help-drawing-recursive-trees/34656/3 "2023-01-06T08:12:50Z")

</div>

Adding a `time.sleep()` won’t help. Probably, moving the branch-drawing logic into your `draw` block would be best. Hopefully, this very simple example helps illustrate what I mean –

```python
def setup():
    size(500, 500)
    frameRate(1)

def draw():
    right = random(0, 1)
    if right > 0.5:
        draw_branch('#FF0000', 'r')
    else:
        draw_branch('#0000FF', 'l')
        
def draw_branch(f, dir):
    stroke(f)
    strokeWeight(2)
    if dir == 'r':
        line(random(width/2), random(height), 250, 0)
    else:
        line(250 + random(width/2), random(height), 250, 0)

```

It just draws random lines on the left (blue) and right (red) halves of the display window, but hopefully that helps.

As the mnse has pointed out, you need to format your code (with the **\</\>** button) so we can see the indentation.

---

<div class="post-metadata">

**Author:** ![tabreturn](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/tabreturn/32/3697_2.png) [@tabreturn](https://discourse.processing.org/u/tabreturn)\
**Post date:** [January 6, 2023, 8:38pm UTC](https://discourse.processing.org/t/help-drawing-recursive-trees/34656/4 "2023-01-06T20:38:39Z")

</div>

… to add to what I wrote before …

Consider that these three code snippets produce the same result, counting from ten down to zero. First, a **recursive function** –

```python
r_limit = 10

def recurse():
    global r_limit
    print(r_limit)
    if r_limit > 0:
        r_limit -= 1
        recurse()
        delay(1000)

recurse()

```

Second, a **while loop** (which you use instead of a _for loop_ when you don’t know ‘up front’ how many iterations you might require) –

```python
r_limit = 10

while r_limit > 0:
    print(r_limit)
    r_limit -= 1
    delay(1000)

```

But you need to draw/render each frame. So here’s a third version that employs the `draw()` block as a loop. Note that the `frameRate()` effectively serves the purpose of the timing argument in the `delay()` functions above –

```python
def setup():
    frameRate(1)

r_limit = 10

def draw():
    global r_limit
    print(r_limit)
    if r_limit > 0:
        r_limit -= 1
    else:
        noLoop()

```

Alternatively, you could use a `draw()` block with some `noLoop();delay(1000);draw()` sequence in it – but to me, that feels more clumsy than letting `frameRate()` do the job for you (unless you need some variable frame rate).