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Issue with moving exhausts

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another_commander
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Re: Issue with moving exhausts

Post by another_commander »

hiran wrote: Tue May 14, 2024 4:08 pm
Is it possible to reproduce such a shot from an inside view? Or without having rotated the camera?
I have never seen it from an inside view, ever. Also, haven't noticed it in external view before any camera rotation (note that we are talking about a paused scene here, otherwise it would be very difficult to notice this anyway).

My theory is that the engine keeps rendering using the depth buffer information from the original scene (before any pause / rotation), which is calculated correctly. But when you rotate it, depth buffer information (or some other OpenGL matrix calculation) should update but it doesn't. Can't prove that without extensive debugging and I could very well be way off the mark, but can''t think of anything else right now.

It is worth noting that the external view camera rotations were a relatively "recent" addition in the game, so it makes some sense that something might have been overlooked.
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Re: Issue with moving exhausts

Post by Commander_X »

The thing that "rotated camera" might affect is the "billboard" texture presentation (i.e. objects always oriented to face the camera). I'd expect z-order not to be affected by camera rotation.
I am not sure though this is how the the exhaust is rendered (that is, if using billboarding), and from the screenshot just a segment of the trail seems to be affected, not the whole object.
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hiran
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Re: Issue with moving exhausts

Post by hiran »

Commander_X wrote: Tue May 14, 2024 5:56 pm
The thing that "rotated camera" might affect is the "billboard" texture presentation (i.e. objects always oriented to face the camera). I'd expect z-order not to be affected by camera rotation.
I am not sure though this is how the the exhaust is rendered (that is, if using billboarding), and from the screenshot just a segment of the trail seems to be affected, not the whole object.
I believe the rendering would either not draw invisible stuff or draw background objects and then foreground objects.

The exhaust trail seems to be a huge object which starts way in the background so it gets rendered early. When the inbetween ship obscures/cuts the trail the engine needs to repaint the front part which does not happen.
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