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Turbo46

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Posted: 07:47pm 27 Sep 2022

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stanleyella said Can a sub be like a function as per passing parameters?

Did you read my post above?

Bill

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stanleyella

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Posted: 07:55pm 27 Sep 2022

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lizby said

stanleyella said Would integers be ok for integers?

Would 3 divided by 2 times 2 yielding 2 be good enough for you? What's the fear of floats? If you're doing division, floats are your friend.

Hmmm. I got to think about that. New to me using mmbasic but worked as 16bit and 32bit vals on 8bit ucntrlr.
I will try using integers because some success withprevious code but now testing the
captain boing map function with looks just whatI wanted but may use just math for scaling a value.
cheers, stan

stanleyella

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Posted: 08:29pm 27 Sep 2022

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Turbo46 said

stanleyella said Can a sub be like a function as per passing parameters?

Did you read my post above?

Bill

Naturally. I read all replies. Your link gave error 404. I from 8 bit do not use subs because the call and return uses the stack but no idea about functions speed.
I got no problem using in line code not subs but if using arrays then repeating same code would use prog mem.. but it is a pico and has plenty so who cares?
Why bother with bits or bytes? use integers and floats for variables

Floats for 1 + 2 just seems new.

Turbo46

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Posted: 09:01pm 27 Sep 2022

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stanleyella said Your link gave error 404

Sorry, you should have said. Try this:

Turbo46 said Another good source of information is Geoff's "Getting Started with the Micromite" from here

stanleyella said Can a sub be like a function as per passing parameters?

Sorry but the fact that you asked that question "after reading my post" and reading the manual just suggested to me that you didn't. I tried to demonstrate and explain just that very thing.

Bill

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Mixtel90

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Posted: 09:09pm 27 Sep 2022

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True that SUBs and FUNCTIONs are slightly slower than inline code, but if they are of any length they'll save you memory, especially if they are used several times. The performance hit from using them isn't much unless they are being called from inside a loop in which case they may slow things down. If you are bothered about speed then use TIMER to measure how long it takes to call a SUB or FUNCTION and return.

It's well worth having a good read about SUBs and FUNCTIONs, as well as about static and local variables. They can make your life a lot easier and enable you to write routines that can be used again in other programs without having to start from scratch.

You generally only DIM an array once. After that it doesn't change how much memory it uses as it's already allocated. The memory used comes out of the variables area, not the program area, so you can have some big arrays.

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stanleyella

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Posted: 09:32pm 27 Sep 2022

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I find the for next final value is strange
vin=3.39 vdeg=270.18181822
I do not see why for vin=0 to 3.3 step 0.01 next got to 3.39 which it does just printing vin

OPTION EXPLICIT
dim vdeg!,vin!
cls
for vin=0 to 3.3 step 0.01
vdeg=Map(vin,0,3.3,0,270)
text 0,0,str$(vin)
text 50,0,str$(vdeg)
next
do
loop

Function Map(x As Float,rLo As Float,rHi As Float,oLo As Float,oHi As Float) As Float
Map=((Min(Max(x,rLo),rHi))-rLo)*((oHi-oLo)/(rHi-rLo))+oLo
End Function

Turbo46

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Posted: 09:49pm 27 Sep 2022

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Works for me. I changed the TEXT for PRINT and tested in MMBasic for DOS

OPTION EXPLICIT
dim vdeg!,vin!
cls
for vin=0 to 3.3 step 0.01
vdeg=Map(vin,0,3.3,0,270)
print str$(vin), str$(vdeg)
next
do
loop

Function Map(x As Float,rLo As Float,rHi As Float,oLo As Float,oHi As Float) As Float
Map=((Min(Max(x,rLo),rHi))-rLo)*((oHi-oLo)/(rHi-rLo))+oLo
End Function

These were the last few values:

3.27 267.5454545
3.28 268.3636364
3.29 269.1818182
3.3 270

Bill

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TassyJim

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Posted: 10:18pm 27 Sep 2022

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Stan is print to the LCD so the '9' is left over form the previous value 3.29
He needs to use str$(Vin,2,2) or erase the 9 in othe rways.

Similar for 270xxxxx

Jim
Edited 2022-09-28 08:18 by TassyJim

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lizby
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Posted: 10:40pm 27 Sep 2022

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stanleyella said

lizby said

stanleyella said Would integers be ok for integers?

Would 3 divided by 2 times 2 yielding 2 be good enough for you? What's the fear of floats? If you're doing division, floats are your friend.

Hmmm. I got to think about that. New to me using mmbasic but worked as 16bit and 32bit vals on 8bit ucntrlr.

Wouldn't work on a PICAXE with integer-only math. On what device does it work for you with unsigned 8-bit math? I'm guessing floats have to be available for intermediate values.

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Turbo46

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Posted: 10:46pm 27 Sep 2022

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Of course. Thanks Jim

So Stan, (just in case...

)your code would be:

OPTION EXPLICIT
dim vdeg!,vin!
cls
for vin=0 to 3.3 step 0.01
vdeg=Map(vin,0,3.3,0,270)
text 0,0,str$(vin,2,2)
text 50,0,str$(vdeg,2,2)
next
do
loop

Function Map(x As Float,rLo As Float,rHi As Float,oLo As Float,oHi As Float) As Float
Map=((Min(Max(x,rLo),rHi))-rLo)*((oHi-oLo)/(rHi-rLo))+oLo
End Function

And Stan, I recommend that you use:

next vin

It can get confusing when you are nesting for/next loops

Bill

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Martin H.

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Posted: 09:01am 28 Sep 2022

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example to Scale a Picture

for better readability I left the data uncompressed

'scale a Picture
Dim Col%(15)
Restore colors:For f%=1 To 15:Read Col%(f%):Next f%
MODE 2
Draw_tree
'SCALE it down
For y%=0 To 44
For x%=0 To 63
� cl%=Pixel(x%,y%)
� Pixel 64+x%/1.25,10+y%/1.25,cl% :'Scale 0.8
� Pixel 116+x%/1.5,16+y%/1.5,cl% :'Scale 0.67
� Pixel 160+x%/1.8,21+y%/1.8,cl% :'Scale 0.55
� Pixel 196+x%/2,24+y%/2,cl% :'Scale 0.5
� Pixel 228+x%/2.5,28+y%/2.5,cl% :'Scale 0.4
� Pixel 254+x%/3,31+y%/3,cl% :'Scale 0.33
� Pixel 276+x%/4,35+y%/4,cl% :'Scale 0.25
� Pixel 292+x%/6,39+y%/6,cl% :'Scale 0.166
Next
Next
Print @(0,128)

Sub draw_tree
Local p%,n%,byt$,m$
�'--- Read/Create Sprite
�Restore Tree
� For p%=0 To 40
� �Read Byt$:Byt$=expand$(Byt$)
� �For n%=1 To Len(Byt$)
� � m$=Mid$(Byt$,n%,1)
� � cl%=Val("&H"+m$):Pixel n%-1,45-p%,COL%(cl%)
� �Next n%
� Next p%
� 'Sprite read #1,0,0,64,45
End Sub

Function expand$(pxl$)
�Local n%,nmb%,tmp$,co$
�For n%=1 To Len(pxl$)
� �If Asc(Mid$(pxl$,n%,1))< 71 Then
� � �tmp$=tmp$+Mid$(pxl$,n%,1)
� �Else
� � �co$=Hex$(Asc(Mid$(pxl$,n%,1))-71)
� � �Inc n%:nmb%=Val("&H"+Mid$(pxl$,n%,1)):tmp$=tmp$+String$(nmb%+1,co$)
� �EndIf
�Next
�expand$=tmp$
End Function

colors:
'--Colorscheme accordung to matherp
Data RGB(BLUE),RGB(GREEN),RGB(CYAN),RGB(RED)
Data RGB(MAGENTA),RGB(YELLOW),RGB(WHITE),RGB(MYRTLE)
Data RGB(COBALT) ,RGB(MIDGREEN),RGB(CERULEAN),RGB(RUST)
Data RGB(FUCHSIA),RGB(BROWN),RGB(LILAC)

Tree:
Data "00000000000000808000AAAAAAAA3AAAA3E3A2A2A0AAA2A08080000000000000"
Data "0000000000000A22A0A2A2A2A2AAACE4EE4EBE2EAAA2AA080000000000000000"
Data "00000000000000000000000000A0A2A3EEEE40E2A2A000000000000000000000"
Data "000000000000000000000000000E0E0EE4CCCC0E0E0000000000000000000000"
Data "00000000000000000000000000000004CCCE0000000000000000000000000000"
Data "00000000000000000000000000000004CC4C0000000000000000000000000000"
Data "00000000000000000000000000000004CCCE0000000000000000000000000000"
Data "00000000000000000000000000000004CCCC0000000000000000000000000000"
Data "0000000000000000000000000000000CCC4E0000000000000000000000000000"
Data "0000000000000000000000000000000CCCCE0000000000000000000000000000"
Data "00000000000800000000000000000CCCE4EE0000000000000000000000000000"
Data "00000000002820002282000000000E4CCCCCC000000000000000000000000000"
Data "000000000ECC0220E8E0200000000CCCCCC4E000000000000288200000000000"
Data "00000E20E0202020E8E020000000E88EEEEE8E000000288E8228200000002000"
Data "023A0222B82A22828282200000000E0CCECCCE0E0000222222AAE8E002202020"
Data "02E822A82282822A828288888888C22882CCC8282828282A3A2B8828E2E88220"
Data "0232222A22228282828E828282228282C88882A2A820A22AB2ABEA20A20E2820"
Data "002AEAAE0EA0AEE0E0E0E0E00EE0000CC000E0AABE0E0EEAEA3AE0BE3E0003E0"
Data "000E2EEAA2A3322E2E8E82A882EE888A888880202A2B83ABAA22A32AA2882000"
Data "000000EEBEAEAEEAEAEAE0EAEAE02AAE00002AA3E0E0BAABABE0ABAA0B820300"
Data "000000E08EE8E2EEAEAEAEEEAEAAEAEAA2EE8BA0EAEAEE0E00E0E0BEAEBE0E00"
Data "00000000EEAAA8EE0E8E88EE8EE8E8EAE8E8E3E8B8EA8E8E8EA8EAEA2AB20000"
Data "0000000E2A23AE0EAEAE8EAEEE8EA0AEEEA3AAE8E8EA8EAE8A38E3ABEA3E0000"
Data "00000000E2EAEAEAEAEA8E3EAAB82AB8EA3E2E8E0E0EEEABABAE3EB2E2000000"
Data "0000000000EAE88E8E8BEEABEE8EE8E8AEAE8E8EE8E8ABAE3AEEAA3E00000000"
Data "00000000000EAEEE3EEEEAEAEAEE822222AE2E8EEAEEA3AB0EEEAA3E00000000"
Data "00000000000EAABAAAA0E0BEA0B0E0EABAAAE8EA0E3A0EEE0EA3EEA2E0000000"
Data "00000000000EA3EE0EBAB0EBEAEAEAEAEEABE8E3EEEEABAEAE0EAA0EE0000000"
Data "0000000000002AAE30E0EAEE0EEEEE0EA0EAEA8E0AAEEEAA0E0E000000000000"
Data "000000000000EA3BEE0EEA30AAE0EA2E2EEE2222EEA3AEB8EE0EE00000000000"
Data "00000000000EEAEE0EAEEAAEEEABA3A3AEAEAAE8EEA8C3B8A3AA200000000000"
Data "00000000000EA2EEAEAE0EEAEABAAAABABA3BABEAE0ABBE8EE2EE00000000000"
Data "0000000000003E3E0EEAE88E8E8E0E0EEAAAE0E0B0EAEAAAEAE0000000000000"
Data "00000000000000023A03A8EE0E8EAE8E8E08AA8EAB8A38BB83E0000000000000"
Data "000000000000002A3A2A3A3E2EAEAA3EEBEEEEAEEBA8AABB2000000000000000"
Data "00000000000000E02E2E32A3E8A3BE8AAE8E88E8AAAEBB2E0000000000000000"
Data "00000000000000002E00E3ABEABAABEEAAEEE8EEEBA2ABE00000000000000000"
Data "00000000000000000C000CCC2A3E020AAEAAE8E2A3A232E00000000000000000"
Data "000000000000000000000000CC0000C33EE3E8EA0EE0E0000000000000000000"
Data "0000000000000000000000000000000C2E08AE22E00000000000000000000000"
Data "00000000000000000000000000000000C0E22EE0000000000000000000000000"
Data "000000000000000000000000000000000C00CAAC000000000000000000000000"

Edited 2022-09-28 20:58 by Martin H.

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lizby
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Posted: 12:00pm 28 Sep 2022

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Martin H. said example to Scale a Picture

Very nice. Thank you.

PicoMite, Armmite F4, SensorKits, MMBasic Hardware, Games, etc. on fruitoftheshed

stanleyella

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Posted: 02:58pm 28 Sep 2022

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Thanks for the replies, sorted the for next prob.
Jim- I should have used a trailing space or formatted the str$(vin).cheers.
Martin- brill demo. I would not have thought of scaling sprites. thanks for sharing.
@Lizby- I have used scale function on 8bit basic that has no floats.
I can find the code if you want. �https://www.youtube.com/watch?v=d51PTF8Boh0

I think captain boing's code is a nice demo with syntax usage and real values demo.
Easy to understand... even for me �

PS.- Bill. Next val advice is sound but if you indent your code then nested for next loops are readable.. but true.. use a next val to be safe and more readable. Thanks.
Edited 2022-09-29 01:16 by stanleyella

lizby
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Posted: 04:14pm 28 Sep 2022

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stanleyella said I have used scale function on 8bit basic that has no floats.
I can find the code if you want.

You have to do tricks to come up with values like 4.35 using only integers, like multiplying your initial value by 100 and then displaying the result divided by 100, then with ".", then with remainder of division by 100.

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stanleyella

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Posted: 04:37pm 28 Sep 2022

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lizby said

stanleyella said I have used scale function on 8bit basic that has no floats.
I can find the code if you want.

True.. it is called improvisation �

edit: I can find 5 year old code for gcb that I am now ashamed of like this a-d meter which was a trig learning experience.
I thought you would wonder how the 8bit sin,cos worked.
It used tables :)
Edited 2022-09-29 03:14 by stanleyella

vegipete

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Posted: 05:19pm 28 Sep 2022

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lizby said

Martin H. said example to Scale a Picture

Very nice. Thank you.

Very nice indeed! Ausgezeichnet!

That scaling algorithm is remarkably effective. Thank you!

Visit Vegipete's *Mite Library for cool programs.

Martin H.

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Posted: 01:20pm 29 Sep 2022

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vegipete said
That scaling algorithm is remarkably effective. Thank you!

It was more for guiding. :-)
There is still room for improvement.
As the routine paints over some pixels that have already been set.
this can be prevented, by changing your view from source to destination.
If a row in destination is just 40 Pixel, then Query just the 40.
;-)

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CaptainBoing

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Posted: 07:22pm 01 Oct 2022

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late to the party coz of personal stuff, but... http://www.fruitoftheshed.com/MMBasic.Map-Function.ashx?HL=map

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