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→Releasing Canvas textures
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== 2022 == | == 2022 == | ||
=== Releasing Canvas textures === | === Releasing Canvas textures === | ||
{{Stub}} | |||
we'd need some kind | |||
of way to delete the texture without deleting the window, redrawing the | |||
texture when the window is reopened ? Starts to sound complicated … but on | |||
the other hand, all windows on the Extra 500 use a custom Window class | |||
which does something similar … <ref>https://sourceforge.net/p/flightgear/mailman/message/37719030/</ref> | |||
I've updated the code to directly hide the window when the close button is | |||
pressed, and also fixed a bug which consisted of the windows automatically | |||
showing (which is not desired when the window is constructed at startup and | |||
should only be shown later). New patch attached. | |||
As for memory usage, I did a test - 100 1000x1000 px canvas windows, all | |||
with destroy_on_close = 0. constructing them didn't give a significant | |||
increase in memory usage - only upon showing them all at once, the RAM | |||
usage went up by 2 GB. that's quite a lot you might say, but 1) most | |||
dialogs are not as big as that and 2) which user opens 100 dialogs in one | |||
session ? In most cases it won't be more than 10 = 200 MB RAM (if all | |||
dialogs were using this new behaviour) - and the default behaviour is to | |||
destroy the window on closing anyways (destroy_on_close = 1 by default, you | |||
got to explicitly set it to 0 to get the new behaviour, also to maintain | |||
backwards compatibility), so I think this won't be an issue.<ref>https://sourceforge.net/p/flightgear/mailman/message/37719123/</ref> | |||
What we’d ideally want is a C++ change so that hidden canvases release their texture memory : it’s created the first time the canvas is rendered, which is why the memory is fine until you actually show them. | What we’d ideally want is a C++ change so that hidden canvases release their texture memory : it’s created the first time the canvas is rendered, which is why the memory is fine until you actually show them. | ||