Programming

Fix Manim OpenGL Text Rendering in Interactive Embed

Troubleshoot Manim CE OpenGL renderer issues with incorrect text or graph rendering in interactive_embed. Quick fixes: switch to Cairo, downgrade IPython to 8.0.1, update Manim. Debug checklist and best practices included.

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Manim CE OpenGL: text or graph rendering incorrect in interactive_embed

I’m testing Manim Community Edition (CE) with the OpenGL renderer using this code:

python
from manim import *

class Test(Scene):
 def construct(self):
 self.interactive_embed()

I render it with:

bash
manim -qm -p --renderer=opengl file.py Test

The interactive session starts from input:9, but the animated graph renders unexpectedly (text not displaying as expected).

What is causing this rendering issue, and how can I fix it?

Your render is broken because two things are colliding: Manim’s OpenGL backend has several known bugs around glyph/texture handling, z-order and “fill” behavior in interactive mode, and interactive_embed can leave the IPython/OpenGL state corrupted (an IPython-version incompatibility is a common trigger). The fastest fixes are to run the scene with the Cairo renderer, downgrade IPython to 8.0.1 (if you need interactive_embed), or upgrade Manim to a version containing the interactive_embed fixes; if you must use OpenGL, render text last and follow the debug checklist below.

Contents

Why manim opengl interactive_embed breaks text rendering

Two separate subsystems are to blame, and they often show up together:

Put simply: OpenGL text handling in Manim has known bugs, and interactive_embed exposes them (or makes them worse) because session/OpenGL state can be left inconsistent.

Quick fixes for manim python interactive sessions

Try these fast checks and workarounds in this order (each one is quick to test):

  1. Render with Cairo (fastest diagnostic). If Cairo shows correct text, it’s an OpenGL-specific problem:
  1. Don’t use interactive_embed while debugging rendering. Replace it with a minimal scene or use plain Write/Text to verify:
python
from manim import *
class CheckText(Scene):
def construct(self):
self.add(Text("Hello World"))
self.wait()

Render with your normal OpenGL flag and compare.

  1. Downgrade IPython (common immediate fix for interactive corruption):

  1. If text is visually present but wrong (aliasing / scaling), try enabling mipmaps or adjust sampling—users have found mipmapping helps scaled text: https://www.reddit.com/r/opengl/comments/cjcske/text_rendering_help/.

  2. Render text last and/or as a separate pass. Depth testing can hide or garble text; ensure text draws after scene geometry or with depth disabled. Community advice: disable depth and enable blending for overlays (render overlay text after objects): https://www.reddit.com/r/opengl/comments/19913hp/problem_with_rendering_texts/.

If Cairo fixes it, that’s the fastest route for production-quality typography.

If you want a durable solution rather than a one-off workaround:

  • Check versions (run in the same environment you use for manim):
bash
python -c "import manim, IPython; print('manim', manim.__version__); print('IPython', IPython.__version__)"

  • Upgrade Manim to the latest release first:

  • pip install -U manim
    Many OpenGL interactive issues have been discussed and patched on the repo; if the release still misbehaves you can install the current main branch (development build) which may include recent PR fixes:

  • pip install git+https://github.com/ManimCommunity/manim.git

  • Apply the interactive_embed/session fixes: there was a merged PR that fixed IPython session history and embedding problems (useful for reducing interactive corruption): https://github.com/ManimCommunity/manim/pull/3306

  • Use a virtualenv. Downgrading IPython system-wide can affect other projects. Create an isolated env for manim testing:

  • python -m venv .venv

  • source .venv/bin/activate

  • pip install manim IPython==8.0.1

  • If you must keep IPython newer than 8.0.1, test whether upgrading Manim to the latest main resolves the corruption; when in doubt, file a reproducible issue (include your manim version, IPython version, OS, GPU/driver and a minimal reproduction) on the Manim repo — reference related issues so maintainers can triage: https://github.com/ManimCommunity/manim/issues/3939 and https://github.com/ManimCommunity/manim/issues/2413.

Debug checklist and minimal repro steps

Use this checklist to isolate the problem and gather data for a bug report:

  1. Minimal repro without interactive_embed:
  • Create a tiny file with just a Text object (example above). Does OpenGL render that correctly?
  1. Switch renderer:
  1. Check IPython:
  • python -c “import IPython; print(IPython.version)”
  • If >=9 and you see corruption in interactive_embed, try pip install IPython==8.0.1 and re-test.
  1. Try the development Manim:
  • pip install git+https://github.com/ManimCommunity/manim.git
  • Re-run your test to see if a recent fix resolved it.
  1. Look for console errors:
  1. Capture a reproducible sequence:
  • Note exact commands, your OS, GPU/driver, manim version, IPython version, and paste a minimal file. Attach logs and links to related issues when filing a bug.
  1. Workarounds to try if you’re comfortable hacking:
  • Render text as a separate scene (or export frames) and composite them outside of OpenGL.
  • Avoid calling interactive_embed before the scene has completed its final render pass.

Best practices for text and graphs in manim opengl

Sources

Conclusion

The rendering oddness you see comes from OpenGL text/font handling bugs in Manim combined with interactive_embed exposing or amplifying session/OpenGL state problems (often tied to IPython version). Quick route: try Cairo; if you need interactive_embed, downgrade IPython to 8.0.1 or update Manim to a build that includes the interactive_embed fixes. If the problem persists after those steps, run the minimal repro above, collect terminal logs, and open a concise issue on the Manim repo (attach manim/IPython versions and the small test file)—that gives maintainers what they need to fix the OpenGL pipeline for everyone.

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Fix Manim OpenGL Text Rendering in Interactive Embed