| |
ws
Registered: Apr 2012
Posts: 229 |
4x4 FLI questions..
So, Onslaught Design uses a gfx mode which I have never consciously observed before, and i was amazed that it actually seems to be all characters, no bitmap, no sprites.
So, do i get this right: like this you can get any of 16 colours next to eachother in a 4x4 pix matrix with only 2x 1k (minus the fli bug gap) ? Or are there neighbouring restrictions, too?
Question2: is there a crossplatform converter for this already, like PNG or BMP to 4x4 Charmode FLI?
Question3: can you point me at a plasma that uses this mode?
Thanks! |
|
| |
ws
Registered: Apr 2012
Posts: 229 |
Oh no. I just understood it actually DOES use bitmap. My bad. Nevermind! |
| |
chatGPZ
Registered: Dec 2001
Posts: 11147 |
There must be converters too (it's trivial) - look for "Zoom4" (or "Zoom8", which is the same but with 8x8 blocks) |
| |
Oswald
Registered: Apr 2002
Posts: 5028 |
zoom4 and zoom8 are really stupid naming, wtf is zoomed ? nothing. |
| |
chatGPZ
Registered: Dec 2001
Posts: 11147 |
Stupid terms in the scene? No way :) |
| |
DKT
Registered: Aug 2004
Posts: 96 |
zoom the pixels in any gfx editor 4 times and you will figure out why it's called zoom4 ;) |
| |
Krill
Registered: Apr 2002
Posts: 2854 |
Quoting wsSo, So, do i get this right: like this you can get any of 16 colours next to eachother in a 4x4 pix matrix with only 2x 1k (minus the fli bug gap) ? Or are there neighbouring restrictions, too? Quoting wsOh no. I just understood it actually DOES use bitmap. My bad. Nevermind! Yes, bitmap mode is required to set two independent colours per 8 pixels wide tile.
To minimise memory usage, you could use the repeated-badline technique rather than extra DMA by FLI.
This would limit the bitmap portion to the first 320 bitmap bytes, but spread out the colour map all over RAM in chunks of 40 bytes.
Interrupt overhead is higher (need an interrupt every 4 rather than 8 rasterlines), but there is no FLI bug and thus full width. |
| |
Oswald
Registered: Apr 2002
Posts: 5028 |
Recently I was wondering if repeating first line of bitmap 4x4 is possible, thanks for the answer :) hadnt had a use case yet tho. |
| |
chatGPZ
Registered: Dec 2001
Posts: 11147 |
The way it scatters the VRAM over memory is a bit... annoying :) |
| |
HCL
Registered: Feb 2003
Posts: 717 |
Yes, the memory usage is very fragmented.. but the interrupt-overhead is probably *not* higher, like Krill suggests, perhaps even lower.. Since there is no FLI-bug involved, the interrupt is not timing critical, and you can also trigger two badlines within the same interrupt.. |
| |
Copyfault
Registered: Dec 2001
Posts: 467 |
Well, initially I wanted to post something very close to what Krill wrote, but then I decided to refrain from it, mainly due to that awful memory scattering already mentioned.
And cheering in to HCL's post: the approach even allows for getting along without any IRQ at all - code interleaving is your friend ;) |
... 13 posts hidden. Click here to view all posts....
|
| Previous - 1 | 2 | 3 - Next |
