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Question concerning the "Overscan" page: http://forums.nesdev.com/viewtopic.php?f=2&t=16178 
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Author:  Firebrandx [ Wed Jul 05, 2017 11:00 am ] 
Post subject:  Question concerning the "Overscan" page: 
My question concerns the following line of the section called "For Emulator Developers": But as a slight optimization, you can scale first (256 * 8/7 = 292) and then pad: stretch the 256x240 pixels to 292x240, 584x480, 876x720, or 1168x960 square pixels or 320x240 or 640x480 nonsquare pixels. Isn't it better math to use scaling before correction? For example, say you want to scale to 4x. My formula for that is (256 * 4) * (8/7), which gives 1170 pixels, not 1168. It adds in that extra bit of accuracy in my opinion to scale before correction, not correct before scaling. 
Author:  tepples [ Wed Jul 05, 2017 11:27 am ] 
Post subject:  Re: Question concerning the "Overscan" page: 
I think I chose the multiples of 292 because 292 is a multiple of 4, making 1168 a multiple of 16. The difference between the two is 1.1406:1 (292/256) as opposed to 1.1429:1 (true PAR). 
Author:  Firebrandx [ Wed Jul 05, 2017 4:56 pm ] 
Post subject:  Re: Question concerning the "Overscan" page: 
tepples wrote: I think I chose the multiples of 292 because 292 is a multiple of 4, making 1168 a multiple of 16. The difference between the two is 1.1406:1 (292/256) as opposed to 1.1429:1 (true PAR). I see, so in the case of digital scaling, 1168 makes each pixel integer scaled, though a hair less accurate than scaling before correcting. On the Framemeister, the horizontal axis is averaged on pixel edges, so 1170 looks just as smooth as any other width. 
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