made a fractal tree thing when bored, forgot about it, then it solved a problem i was stuck on for days

so i was bored one night and made this little tree simulation thing. took like an hour, thought it was cool, then forgot about it for months in my trash folder.

later i was working on pathforge (interactive fiction tool) and spent days trying to figure out tree layouts for story nodes. nothing was working.

then i remembered that old file...

here's the core part:

class Branch:
    def __init__(self, start, angle, length, depth):
        self.start = start
        self.angle = angle
        self.length = 0
        self.target_length = length
        self.depth = depth
        self.finished = False
        self.children = []
        self.static = False

    def grow(self):
        if self.length < self.target_length:
            self.length += GROWTH_SPEED
        else:
            if not self.finished and self.depth < MAX_DEPTH:
                self.finished = True
                end = self.get_end()
                num_branches = random.choice([2, 3])
                for _ in range(num_branches):
                    delta = random.uniform(-BRANCH_ANGLE, BRANCH_ANGLE)
                    new_length = self.target_length * random.uniform(0.8, BRANCH_FACTOR)
                    if new_length >= MIN_BRANCH_LENGTH:
                        child = Branch(end, self.angle + delta, new_length, self.depth + 1)
                        self.children.append(child)

basically each branch grows and spawns kids when it's done. random angles make it look natural.

ended up using this for pathforge's tree layout and it works pretty well.

full code on github