4-post thread, 2 images, Aug 6 2023. Same day as the RDNA2 assembler design doc (1688286623375454208). SPC project: vintage 640x480 VGA style render + 640x240 fallback for 15 KHz arcade CRTs (PGM-esk) + CRT shader scaling on Deck + OLED/LCD. Mix of render pixel aspect changes, less than 480 lines, letter-box for integer Y scaling. 15 KHz output path docked: HD Fury Nano (no <480p) -> HDMI-to-VGA -> sync combiner (GBS-C bug workaround) -> GBS-C line-drops 480p60 to 240p60 component. Bitmap font uses right angles + 2x2 stroke in 8x16 (pow2) so 640x240p still gets readable 8x8. Overscan safety: Y axis easy - keep cursor pinned in 'safe' zone, still print lines in overscan area (visible on non-overscan CRTs).
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title, author, handle, post_url, post_id, timestamp, post_count, reply_count, repost_count, like_count, view_count
| title | author | handle | post_url | post_id | timestamp | post_count | reply_count | repost_count | like_count | view_count |
|---|---|---|---|---|---|---|---|---|---|---|
| The next challenge is overscan safety, since real non-VGA CRTs will be used in d | NOTimothyLottes | @NOTimothyLottes | https://x.com/NOTimothyLottes/status/1688022114962374656 | 1688022114962374656 | 2023-08-06 03:00:08 | 4 | 0 | 0 | 1 | 340 |
@NOTimothyLottes — The next challenge is overscan safety, since real non-VGA CRTs will be used in d
Post 1 (2023-08-06 02:45:18)
1st SPC project: to be based on vintage 640x480 render (VGA style), +fallback to 640x240 for 15 KHz arcade CRTs (PGM-esk), and CRT shader scaling on Deck and OLED/LCD. Use mix of render pixel aspect changes, running less than 480 lines, and letter-box to keep integer Y scaling.
Post 2 (2023-08-06 02:50:32) — reply to Post 1
My 15 KHz CRT output path when docked is HD Fury Nano (won't do <480p) doing HDMI to VGA, with a sync combiner (to workaround GBS-C bug), into GBS-C which line drops 480p ~60Hz to 240p ~60Hz and outputs component. The 640 width gets maintained even if some CRTs cannot resolve it.
Post 3 (2023-08-06 02:57:50) — reply to Post 2
Presents issues for UI, namely that my bitmap fonts need to look good in both 480p and 240p modes, so for editor (assembler) I'm going with a font that uses right angles and designed around 2x2 stroke width, in a 8x16 (pow2) bitmap, so 640x240p still gets a readable 8x8 (below)
Post 4 (2023-08-06 03:00:08) — reply to Post 3
The next challenge is overscan safety, since real non-VGA CRTs will be used in development. The Y axis has an easy fix, simply keep cursor pinned in the 'safe' zone, but still print lines in the overscan area (so they can be seen when attached to non-overscan CRTs/etc too).

