USAGE OF VLOAD BVLOAD

[ahenry3068]

I want to use VLOAD and or BVLOAD to save and then restore and image
in SCREEN MODE $80.

This is for my Hangman Game. The initial scene takes some time to draw
especially now that I added clouds. It will have to be redrawn before each round
of play when I start implementing game code (which is imminent).

I did not find a corresponding VSAVE OR BVSAVE in the DOCS.
I don't know enough about the memory map of the VERA to
do this without some pointers at this time ... Has anyone
got any example code to point me to ?????

[TomXP411]

I don't think there is a VSAVE. Typically, you'd either copy the data to main RAM and save from there, or you'd write the data to disk one byte at a time.

[ahenry3068]

Is all the Memory for the graphics screen in MODE $80 contiguous ?

[DragWx]

The bitmapped graphics framebuffer (i.e., what you get when you use LINE, FRAME, etc) is at VERA $00000..$12BFF, and should just be one byte per pixel in raster order.

[ahenry3068]

65535 bytes in the first Bank... 11265 in the 2nd bank ???


$00 = Black, $FF = Bright Magenta (with the default pallette of course)

[ahenry3068]

I could do 3 or 4 consecutive BSAVES

Question: CPU Cycles.

[TomXP411]

If you use OPEN, PRINT#, and VPEEK, you can just do it in one big loop. Actually, I'd probably just do it in two loops; write the first 65536 bytes in the first loop, then switch banks and write the last 11K.

[ahenry3068]

Ok I tried that with this code..

Code: Select all

15000 OPEN 20,8,0,"BG.SCN,W"
15010 FOR P = 0 TO 65535
15020   PRINT#20,CHR$(VPEEK(1,P))
15021   PRINT P,
15030 NEXT P
15040 FOR P = 0 TO 11264
15050   PRINT#20,CHR$(VPEEK(2,P))
15051   PRINT 2,P
15060 NEXT P
15070 CLOSE 20
15080 RETURN

It ran without errors(took long enough that I don't think I'm going to use it now.....BUT)
But I cannot find the file "BG.SCN" which should exist after this executed.

[ahenry3068]

I'm having problems with the OPEN syntax... The usual Syntax
in previous BASICS I've used has been OPEN # 20, "OUTFILE.TXT" FOR (READ,WRITE,APPEND).



Any help is welcome.

[ahenry3068]

I really need to understand this to finish my game also......