3 ms·
Interesting, please do tell more! I know that Wolf3D on the SNES uses Mode 7. Not for the walls or sprites, but for the entire screen. The graphics are rendere
by JohnBooty 2y ago
Interesting, please do tell more!
I know that Wolf3D on the SNES uses Mode 7. Not for the walls or sprites, but for the entire screen. The graphics are rendered into a background tiles with a resolution of like 175x100 or something, then scaled up with Mode7 to fill the 224x192 screen. (those aren't the exact numbers, but you get the idea)
- Dwedit 2y agoThe "mosaic trick" is a way to perform horizontal pixel doubling in hardware rather than software. And to do this trick, you turn on the SNES's Mosaic feature, scroll 1 pixel to the left every other scanline, and scroll upward one pixel after each two scanlines have been drawn. Normally the SNES mosaic feature just the top-left pixel of a 2x2 square into that entire square. But the trick makes a different set of pixels get doubled horizontally on the next scanline. It requires a different arrangement of pixels than the normal way of drawing tiles. A tile containing these pixels: 01234567 becomes this when viewed on two scanlines: 00224466 11335577 Actually performing these scroll writes does not require any CPU intervention because you use the SNES's HDMA feature to do those scroll writes. User "93143" on Nesdev describes the Mosaic trick in this post: https://forums.nesdev.org/viewtopic.php?p=205633#p205633 https://forums.nesdev.org/viewtopic.php?p=205633#p205633, other discussion here: https://forums.nesdev.org/viewtopic.php?t=20393&start=135 https://forums.nesdev.org/viewtopic.php?t=20393&start=135 --- So now that you've done this, you need half as much video memory as before, which effectively doubles your bandwidth for rendering and transfers.
- JohnBooty 2y agoWOW! That is so cool! Thank you, thank you, thank you for this reply.