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Aspect correction weirdness

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First post, by VileR

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Something I noticed when playing around with CGA composite output.

Using "machine=cga" and "aspect=true", the CGA's regular 640x200 2bpp mode is correctly scaled to 640x480. However, in composite output mode (M_CGA16), the same underlying resolution is stretched to 640x551?

this happens in both 0.74 and recent SVN (output/scaler are irrelevant).... screenshots attached.

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Reply 1 of 3, by ripsaw8080

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CGA B&W video mode issue with machine=vga

The linked thread was primarily about the erroneous double-double height aspect ratio of mode 6 in VGA machine types, but there's also a mention of composite mode's ratio being off. 😉

Reply 2 of 3, by VileR

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ah, thanks for the heads-up. Now that I checked, the issue doesn't happen with Megabuild 6 - it seems to calculate aspect in an entirely different way, which I assume is more proper than a workaround. Hopefully this change will make it into SVN at some point.

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Reply 3 of 3, by ripsaw8080

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The aspect ratio stuff in MB6 was still off in some ways, but dunno how much Hal has changed it since then. For example mode 10h (640x350x16) is displayed as 640x441 with machine=svga_s3 and 640x453 with machine=ega. In 0.74 and SVN the same mode is displayed as 640x480 with machine=svga_s3 and 799x350 (wide!) with machine=ega. Interesting that the EGA machine type is the one having trouble with an EGA mode...

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