Fix impostor clip zoom - #1063
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Cylinder/hyperball impostors pinned box vertices near the far plane (gl_Position.z = 0.99 / 1.0), which clipped corners still in front of the camera on close zoom. Pin to 0.0 (requires only w > 0) instead.
examples/scripts/test/clip-dist-zoom.js loads a small structure with licorice/ball+stick, sets clipDist to 0 and shows a HUD; scroll-zoom onto a bond to verify it no longer vanishes. Press 'c' to toggle clipDist between 0 and 10. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Thanks, I don't have a huge amount to work on NGL now but this does look sensible. Does it behave correctly in orthographic mode too as well as perspective? |
…pdate instructions
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Yes — it's correct in orthographic too. In ortho gl_Position.w is always 1, so the clip test is just -1 ≤ z ≤ 1 and the per-corner w never shrinks toward zero the way it does in perspective — so the vanishing the fix addresses can't occur there in the first place. Both the old 0.99 and the new 0.0 sit safely inside the range, so ortho behavior is unchanged. I added an o key to the example scene to toggle perspective/orthographic so it's easy to confirm both modes. I've updated the PR to have an example that let you validate functionality pressing "o" key that toggles between orthographic and prespective view. And I don't see any visually problem when the camera is really close. |
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I've needed to show molecule in very high zoom so when I changed clipDist to 0 and zoomed, the bond was disapearing halfway to the end of the bond.