Screenshots are off by one frame

Minuous · 26 March 2015, 19:13

I have been making a lot of screenshots with WinUAE 3.0.0 and I noticed that the generated screenshots don't actually correspond to what is shown on the screen: they are one frame earlier or later, at least as far as the palette is concerned.

(This causes problems with eg. Druid 2 game when using "Deathland" powerup, which changes the palette every few frames. It is impossible to tell from looking at the WinUAE screen which palette has been saved in the screenshot, necessitating taking a whole series of screenshots in rapid succession and then loading them into a paint program to check whether any of them have the desired palette.)

My apologies if this bug has already been reported: I did a search and noticed that "RTG mode screenshots in 16-bit host color depth mode had wrong colors" has been fixed, but this appears to be a different bug (as the game uses OCS not RTG).

Toni Wilen · 29 March 2015, 17:30

It is not a bug, at least not if you use "before filtering" option. Screenshot comes from internal buffer, not what you see and depending on display settings (number of backbuffers), delay may be up to 4 frames.

Some kind of burst screenshot option probably is better solution (takes 10 or so screenshot frames automatically).

26 March 2015, 19:13	#1
Minuous Coder/webmaster/gamer Join Date: Oct 2001 Location: Canberra/Australia Posts: 2,651	Screenshots are off by one frame I have been making a lot of screenshots with WinUAE 3.0.0 and I noticed that the generated screenshots don't actually correspond to what is shown on the screen: they are one frame earlier or later, at least as far as the palette is concerned. (This causes problems with eg. Druid 2 game when using "Deathland" powerup, which changes the palette every few frames. It is impossible to tell from looking at the WinUAE screen which palette has been saved in the screenshot, necessitating taking a whole series of screenshots in rapid succession and then loading them into a paint program to check whether any of them have the desired palette.) My apologies if this bug has already been reported: I did a search and noticed that "RTG mode screenshots in 16-bit host color depth mode had wrong colors" has been fixed, but this appears to be a different bug (as the game uses OCS not RTG).

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29 March 2015, 17:30	#2
Toni Wilen WinUAE developer Join Date: Aug 2001 Location: Hämeenlinna/Finland Age: 49 Posts: 26,534	It is not a bug, at least not if you use "before filtering" option. Screenshot comes from internal buffer, not what you see and depending on display settings (number of backbuffers), delay may be up to 4 frames. Some kind of burst screenshot option probably is better solution (takes 10 or so screenshot frames automatically).

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