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berighteous
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Joined: 18/07/2020
Location: United States
Posts: 110

Posted: 09:49pm 08 Aug 2020

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Hi!
I just got my CMM2 a few days ago and I'm having fun playing with it. I'm starting with porting over a game I did for the pc vga 320x200x256 in 1996. I have all the artwork in binary data files, each byte a color value 0-ff from the clut for a pixel for a sprite.

For example one of the files starts with 30 animation frames of a 29x27 pixel asteroid, followed by 24 frames of the ship rotating with and without thrusters, etc. couple hundred images worth of pixel color data.

I figure I can load the pixel data one by one and pixel them in the correct order on a non visible screen and then cut them and blit them as I need them.

How do I read in the bytes and convert them to color values to pixel? Converting the data files to text numbers with line feeds to INPUT #1,c say works and I can display the correct colors with pixel j,i,map(c) works, but makes the data file 2-3 x it's original size. And it's extra effort massaging all the data files.

How can I read the hex data directly and use it? I saw someone mention str2bin but I don't understand how it works. I need to read the data a byte at a time. (unless there's a better way to do it) can someone explain the process?

Thanks

berighteous
Senior Member

Joined: 18/07/2020
Location: United States
Posts: 110

Posted: 09:55pm 08 Aug 2020

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here's what it looks like doing it the hard way. �Here's the code. The colored line at the bottom is the 8 bit palette.

mode 3,8
'load bmp "bkgr1.bmp"
open "palette.dat" for input as #2
for i = 0 to 255
input #2,r,g,b
map(i)=rgb(r,g,b)
next i
close #2
map set

for i = 0 to 255
pixel i,150,map(i)
next

open "newstuff.dat" for input as #1
for k = 0 to 10
for i = 0 to 26
for j = 0 to 28
input #1,c
pixel 30*k+j,i,map(c)
next j:next i:pause 100 :next k

Edited 2020-08-09 07:56 by berighteous

TassyJim

Guru

Joined: 07/08/2011
Location: Australia
Posts: 6283

Posted: 09:58pm 08 Aug 2020

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From the manual

Quote INPUT$(nbr, [#]fnbr) Will return a string composed of �nbr� characters read from a file on the SD
card previously opened for INPUT with the file number �#fnbr�. This
function will read all characters including carriage return and new line
without translation.

To get the binary values, start by reading the file one 'character' at a time and convert it to binary with

c$ = INPUT$(1,#1)
p = asc(c$)

Jim

VK7JH
MMedit

berighteous
Senior Member

Joined: 18/07/2020
Location: United States
Posts: 110

Posted: 10:10pm 08 Aug 2020

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Thanks. �I didn't understand why i couldn't just read in the data as numbers. Reading ascii and converting to numbers seems really weird to me. I knew there'd be a simple solution. �I'm trying to go through the manuals but the old grey matter she ain't what she used to be!

Here's a video of the PC game https://www.youtube.com/watch?v=hJMQlca0DxM
Edited 2020-08-09 08:13 by berighteous

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