DPC+ Scrolling - Start & End Column?

[Captain Spazer]

Sorry for asking on the subject of DPC+ scrolling again, I don't quite get it, I can get the playfield to scroll with pfscroll 255 which makes the playfield scroll down, but it shoots down and the playfield is empty for a while before coming around, I understand this is because I haven't set a starting and ending column, and from what I've gathered this is where DF0FRACINC Playfield Data comes in?

 

Anyway, my question would be, how would I need to formulate a code for the playfield to scroll down, and designate a starting and ending column?

[+Random Terrain]

All I know about it is what is in this example program:

 

randomterrain.com/atari-2600-memories-batari-basic-commands.html#ex_dpc_scroll

[Captain Spazer]

Hm, I feared as much, Ah well, I can still work with color scrolling for pretty much the same effect. Thanks

[iesposta]

You have to make your Playfield data very tall.

Then there is a bB limit on the data size. I think PlayField data up to 256 bytes.

If you use double line Playfield resolution, you are not going to go far into the new data of one Playfield before it wraps back to the start.

If you use a 4-line Playfield, you can scroll into (guessing) 4 screens of PF squares/ rectangles before it wraps.

 

Creative: Jump to different parts of the Playfield. Find spots where it appears seamless.

Creative: Define another long Playfield and scroll up and down that.

 

Note: Even switching banks, you only have DPC+ 4K graphics bank for playfields, colors, P0 & P1 shapes/colors.

I got around that limit by drawing the entire screen with pfpixel on/off from a data table. I wanted 4 static single line screens, and only 2 fit in 4K with the other display data that the DPC+ 4K data bank uses.

 

This I made using scrolling background colors, scrolling 2-line PF and PF colors.

Press the button to jump down into the Playfield data.

See the bug where it is scrolling too far and changing the score background?

TIA20140730B.bas.bin

[Captain Spazer]

Clever solution, thanks =)