Saving an animation as frames¶
Twelve coloured dots go round in a circle. f.save_frames() saves 30 numbered pictures of it, which loop without a jump when they are joined up.
How it works¶
- f.save_frames("frames/####.png", 30) saves this frame and the next 29. The #### is replaced by the frame number: frames/0001.png, frames/0002.png and so on.
- It is called once, on the first frame, by the test f.frame_count == 0.
- The twelve dots are 30 degrees apart. The animation turns by 30 degrees in 30 frames, so the last frame leads straight back to the first.
- The colour and the size depend only on the angle, so they join up too. f.hsb() makes the colour.
- A program such as ffmpeg can join the pictures into a video or a GIF. Chapter 13 of the guide shows how.
Make it yours¶
- Change the 140 in the dot position to make a bigger or smaller circle.
- Change the size of the dots: the 30 in f.circle() is the middle size.
- Change the 30 in f.save_frames() to save fewer or more pictures.
- Change the 80 in f.hsb() to make the colours paler or stronger.
- Change the folder: "pics/####.png".
The code¶
Copy it into a file and run it.
"""Saving an animation as frames
Twelve coloured dots go round in a circle. f.save_frames() saves 30 numbered pictures of it, which
loop without a jump when they are joined up.
How it works:
- f.save_frames("frames/####.png", 30) saves this frame and the next 29. The #### is replaced by
the frame number: frames/0001.png, frames/0002.png and so on.
- It is called once, on the first frame, by the test f.frame_count == 0.
- The twelve dots are 30 degrees apart. The animation turns by 30 degrees in 30 frames, so the last
frame leads straight back to the first.
- The colour and the size depend only on the angle, so they join up too. f.hsb() makes the colour.
- A program such as ffmpeg can join the pictures into a video or a GIF. Chapter 13 of the guide
shows how.
Make it yours:
- Change the 140 in the dot position to make a bigger or smaller circle.
- Change the size of the dots: the 30 in f.circle() is the middle size.
- Change the 30 in f.save_frames() to save fewer or more pictures.
- Change the 80 in f.hsb() to make the colours paler or stronger.
- Change the folder: "pics/####.png".
"""
import math
import funground as f
def setup():
f.size(640, 400)
def draw():
f.background("black")
f.no_stroke()
for i in range(12):
angle = f.frame_count + i * 30 # 30 frames turn 30 degrees: back to the start
x = 320 + 140 * math.cos(f.radians(angle))
y = 200 + 140 * math.sin(f.radians(angle))
f.fill(f.hsb(angle % 360, 80, 100)) # colour and size depend on the angle only
f.circle(x, y, 30 + 10 * math.sin(f.radians(angle * 3)))
if f.frame_count == 0:
f.save_frames("frames/####.png", 30) # 30 pictures that loop seamlessly
f.run()