| """Look of the README animation: white background, one hue per loop, one text colour.""" |
| import os |
| import shutil |
| import subprocess |
| from pathlib import Path |
|
|
| import matplotlib |
| import numpy as np |
|
|
| matplotlib.use("Agg") |
| import matplotlib.pyplot as plt |
| from matplotlib.colors import LinearSegmentedColormap, to_rgb |
|
|
| BG = "#FFFFFF" |
| TEXT = "#1F2328" |
| WARP = "#D3D9E3" |
| LOOP_CMAP = LinearSegmentedColormap.from_list("loops", ["#3A5BD9", "#2BA89A", "#F08A4B"]) |
| FPS = 24 |
| W, H_PX, DPI = 12.0, 6.0, 100 |
|
|
| plt.rcParams.update({"font.family": "DejaVu Sans", "text.color": TEXT}) |
|
|
|
|
| def loop_color(t, n): |
| return LOOP_CMAP(t / max(n - 1, 1)) |
|
|
|
|
| def ease(p): |
| p = min(max(float(p), 0.0), 1.0) |
| return p * p * (3 - 2 * p) |
|
|
|
|
| def ease_out(p): |
| p = min(max(float(p), 0.0), 1.0) |
| return 1 - (1 - p) ** 3 |
|
|
|
|
| def mix(c1, c2, p): |
| a, b = np.array(to_rgb(c1)), np.array(to_rgb(c2)) |
| return tuple(a + (b - a) * min(max(p, 0.0), 1.0)) |
|
|
|
|
| def new_frame(): |
| fig = plt.figure(figsize=(W, H_PX), dpi=DPI, facecolor=BG) |
| ax = fig.add_axes([0, 0, 1, 1]) |
| ax.set_facecolor(BG) |
| ax.axis("off") |
| return fig, ax |
|
|
|
|
| def glow_line(ax, xs, ys, color, lw, alpha=1.0, z=3, glow=True): |
| if glow: |
| for k, a in ((5.0, 0.05), (2.6, 0.12)): |
| ax.plot(xs, ys, color=color, lw=lw * k, alpha=a * alpha, zorder=z, solid_capstyle="round") |
| ax.plot(xs, ys, color=color, lw=lw, alpha=alpha, zorder=z + 0.1, solid_capstyle="round") |
|
|
|
|
| def glow_dot(ax, x, y, color, size, alpha=1.0, z=5): |
| for k, a in ((5.0, 0.06), (2.6, 0.16)): |
| ax.scatter([x], [y], s=(size * k) ** 2, color=color, alpha=a * alpha, zorder=z, edgecolors="none") |
| ax.scatter([x], [y], s=size ** 2, color=color, alpha=alpha, zorder=z + 0.1, edgecolors="none") |
|
|
|
|
| def encode_gif(src_args, gif: Path, width=1000, colors=96, lossy=int(os.environ.get("GIF_LOSSY", "12"))): |
| """ffmpeg palette GIF without dithering (dither speckles the dark background), then gifsicle.""" |
| vf = (f"scale={width}:-1:flags=lanczos,split[a][b];[a]palettegen=max_colors={colors}:stats_mode=full[p];" |
| "[b][p]paletteuse=dither=none") |
| subprocess.run(["ffmpeg", "-y", "-loglevel", "error", *src_args, "-vf", vf, str(gif)], check=True) |
| if shutil.which("gifsicle"): |
| subprocess.run(["gifsicle", "-O3", *([f"--lossy={lossy}"] if lossy else []), "-b", str(gif)], check=True) |
|
|
|
|
| class Recorder: |
| """Save frames, then encode a GIF (palette per clip) and an MP4.""" |
|
|
| def __init__(self, frames_dir: Path): |
| self.dir = frames_dir |
| shutil.rmtree(self.dir, ignore_errors=True) |
| self.dir.mkdir(parents=True) |
| self.n = 0 |
| |
| raw = os.environ.get("PREVIEW", "").strip() |
| self.preview = {int(x) for x in raw.split(",")} if raw else None |
|
|
| def add(self, fig): |
| if self.preview is None or self.n in self.preview: |
| fig.savefig(self.dir / f"{self.n:05d}.png", facecolor=BG) |
| plt.close(fig) |
| self.n += 1 |
|
|
| def encode(self, gif: Path, mp4: Path = None, width=1000, colors=96): |
| if self.preview is not None: |
| print("preview frames in", self.dir) |
| return 0.0 |
| gif.parent.mkdir(parents=True, exist_ok=True) |
| src = ["-framerate", str(FPS), "-i", str(self.dir / "%05d.png")] |
| encode_gif(src, gif, width, colors) |
| if mp4 is not None: |
| mp4.parent.mkdir(parents=True, exist_ok=True) |
| subprocess.run(["ffmpeg", "-y", "-loglevel", "error", *src, "-c:v", "libx264", "-pix_fmt", "yuv420p", |
| "-crf", "18", "-vf", "scale=trunc(iw/2)*2:trunc(ih/2)*2", str(mp4)], check=True) |
| if not os.environ.get("KEEP_FRAMES"): |
| shutil.rmtree(self.dir) |
| return gif.stat().st_size / 1e6 |
|
|
