Rendering hangs on macOS (crashes on Ubuntu) after few thousands of calls to render()

[jzy3d]

Problem

macOS hangs as follow

Ubuntu crashes and the stack trace indicates that the JOGL "legacy" TextRenderer is culprit.

Disabling the legacy text rendering on macOS prevents hanging.

Explanation

This is due to a memory leak in the recent usage of the "legacy" jogl TextRenderer (which has been introduced to allow text rotation on native charts).

Solutions

One of:

• Disable text rendering from Jzy3D using Jzy3D's TextRenderer.setUseGlutBimap(true). Rotated text won't be rotated and fonts will be limited to Helvetica & Arial.
• Look at a long time pending MR on JOGL providing fixes to memory leaks on TextRenderer.
• Use the JOGL alternative for text management.
• Integrate Latex image renderer and define LatexTextRenderer properly layouting images in 2D (EmulGL) / 3D (PostRenderer). Verify first can change font, style, height with Scilab Latex Renderer.

[jzy3d]

The problem actually arose here : after needing to re-initialize the GLCanvas, the text renderer lost its cache, hence the caching mecanism has been disabled because of a lacking cache invalidation.

Use the following classes

• TestAddRemoveFromFrame can replay a GLCanvas re-init.
• MemoryLeak can reproduce the original memory leak.

So another solution would be to trigger text invalidation when GLEvenListener.dispose() gets called.

[jzy3d]

Other outcome of the analysis : the JOGL MR related to TextRenderer (which has been extracted in a standalone project here) is working better but is not perfect

• The hang (or crash) occurs later but still occurs.
• The quality of text rendering is much better.