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Small and Subtle colour change in animated object

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  Small and Subtle colour change in animated object Richard Ashbery <basura@invalid.addr.uk> - 2019-03-23 12:06 +0000
    Re: Small and Subtle colour change in animated object druck <news@druck.org.uk> - 2019-03-24 21:40 +0000
      Re: Small and Subtle colour change in animated object Richard Ashbery <basura@invalid.addr.uk> - 2019-03-25 13:48 +0000
        Re: Small and Subtle colour change in animated object druck <news@druck.org.uk> - 2019-03-25 20:26 +0000
          Re: Small and Subtle colour change in animated object Richard Ashbery <basura@invalid.addr.uk> - 2019-03-26 11:31 +0000

#5733 — Small and Subtle colour change in animated object

MODE 1920,1080,8 : OFF
x = 0
REPEAT
    CIRCLE FILL x,1100,100
    x+=10
    Z=INKEY(10)
UNTIL x=3800

This simple code draws a filled circle across screen. Has anyone got a
routine I could add to make each new circle go through a gradual
colour change? Only very small and subtle changes of colour are
required to cover the whole of the RGB spectrum. Routine would need to
handle thousands of colours because each prime colour has 256 possible
levels.

Richard

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#5734

On 23 Mar 2019 Richard Ashbery <basura@invalid.addr.uk> wrote:

> MODE 1920,1080,8 : OFF
> x = 0
> REPEAT
>     CIRCLE FILL x,1100,100
>     x+=10
>     Z=INKEY(10)
> UNTIL x=3800

> This simple code draws a filled circle across screen. Has anyone got a
> routine I could add to make each new circle go through a gradual
> colour change? Only very small and subtle changes of colour are
> required to cover the whole of the RGB spectrum. Routine would need to
> handle thousands of colours because each prime colour has 256 possible
> levels.

Try this, it not my best code, but I'm really rusty in BBC BASIC.
As you want thousands of colours I've decreaed the increment to 2, to give 
1920 steps as opposed to 380 above.

ON ERROR PRINT REPORT$;" at line ";ERL:END
MODE 1920,1080,32 : OFF
x% = 0
REPEAT
    c  = (x%/3800)*7
    i%  = (c*256)MOD256
    d%  = 255-i%
    c% = c
    CASE c% OF
      WHEN 0
        r% = i%
        g% = 0
        b% = 0
      WHEN 1
        r% = 255
        g% = i%
        b% = 0
      WHEN 2
        r% = d%
        g% = 255
        b% = 0
      WHEN 3
        r% = 0
        g% = 255
        b% = i%
      WHEN 4
        r% = 0
        g% = d%
        b% = 255
      WHEN 5
        r% = i%
        g% = 0
        b% = 255
      WHEN 6
        r% = 255
        g% = i%
        b% = 255
    ENDCASE
    GCOL r%,g%,b%
    CIRCLE FILL x%,1100,100
    x%+=2
    Z%=INKEY(10)
UNTIL x%>=3800


---druck

-- 
The ARM Club Free Software - http://www.armclub.org.uk/free/
32 bit Conversions Page    - http://www.armclub.org.uk/32bit/

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#5735

In article <15c1f69957.druck@druck.org.uk>,
   druck <news@druck.org.uk> wrote:
> On 23 Mar 2019 Richard Ashbery <basura@invalid.addr.uk> wrote:

[snip]

> > Routine would need to
> > handle thousands of colours because each prime colour has 256 possible
> > levels.

> Try this, it not my best code, but I'm really rusty in BBC BASIC.
> As you want thousands of colours I've decreaed the increment to 2, to give 
> 1920 steps as opposed to 380 above.

> ON ERROR PRINT REPORT$;" at line ";ERL:END
> MODE 1920,1080,32 : OFF
> x% = 0
> REPEAT
>     c  = (x%/3800)*7
>     i%  = (c*256)MOD256
>     d%  = 255-i%
>     c% = c
>     CASE c% OF
>       WHEN 0
>         r% = i%
>         g% = 0
>         b% = 0
>       WHEN 1
>         r% = 255
>         g% = i%
>         b% = 0
>       WHEN 2
>         r% = d%
>         g% = 255
>         b% = 0
>       WHEN 3
>         r% = 0
>         g% = 255
>         b% = i%
>       WHEN 4
>         r% = 0
>         g% = d%
>         b% = 255
>       WHEN 5
>         r% = i%
>         g% = 0
>         b% = 255
>       WHEN 6
>         r% = 255
>         g% = i%
>         b% = 255
>     ENDCASE
>     GCOL r%,g%,b%
>     CIRCLE FILL x%,1100,100
>     x%+=2
>     Z%=INKEY(10)
> UNTIL x%>=3800

Many thanks Druck. I wish I could write a program as quickly as that!
Works a treat - just the job. I see you use MODE 1920,1080,32 which
makes a significant difference to the colour graduation smoothness. 

Presumably you've expanded the WHEN statements to make it clearer for
me but by combining each r,g,b parameter group into each WHEN line
almost halves the number of lines making routine quite compact.

I can link your routine with a rather unusual but very effective
multi-pattern pseudo 'lissajous' program written in BB4W.

Thanks again

Richard

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#5736

On 25/03/2019 13:48, Richard Ashbery wrote:
> Many thanks Druck. I wish I could write a program as quickly as that!
> Works a treat - just the job. I see you use MODE 1920,1080,32 which
> makes a significant difference to the colour graduation smoothness.

No worries. I was able to do it remotely via VNC to my ARMx6 minim.

> Presumably you've expanded the WHEN statements to make it clearer for
> me but by combining each r,g,b parameter group into each WHEN line
> almost halves the number of lines making routine quite compact.

Yes, it was a simple cut & paste job, and can be expressed far more simply.

> I can link your routine with a rather unusual but very effective
> multi-pattern pseudo 'lissajous' program written in BB4W.

Put it on some web space somewhere so we can all see it.

---druck

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#5737

In article <q7bdhi$q7i$1@dont-email.me>, druck <news@druck.org.uk>
wrote:

[snip]

> > I can link your routine with a rather unusual but very effective
> > multi-pattern pseudo 'lissajous' program written in BB4W.

> Put it on some web space somewhere so we can all see it.

Unfortunately I'm without webspace at the moment. I've been too busy
with other projects to sort out a new provider. I'll try and do that
as soon as I've arranged webspace and got the program working
properly.

Regards

Richard

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