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Volhout
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Joined: 05/03/2018
Location: Netherlands
Posts: 5684

Posted: 11:30am 10 Feb 2026

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Hi Mick,

Both you and Tom are right. If I look at (but .. who am I ?) my personal application domain, I would
- on RP2040 VGA have loved to trade RAY with STRUCTURES.
- on RP2040 microcontroller domain have loved to trade STEPPER for STRUCTURES.
- on any RP2040 would have dismissed TURTLE.

But that is me. I do not see the value in structures. But I know from the enthusiastic communication at the introduction of structures, that many do love it.
And TURTLE has it's own audience (my grand children are to grown up, but they may have loved it once). Maybe for my grand-grand children in 10 years.

Anyway. It is what it is.

Volhout

PicomiteVGA PETSCII ROBOTS

mozzie
Senior Member

Joined: 15/06/2020
Location: Australia
Posts: 204

Posted: 01:34pm 10 Feb 2026

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G'day,
It probably shows the strength of the whole MMbasic / Picomite platform that with so many different users and use cases, it appears to satisfy 99% of them 99% of the time.
This is a huge ask from any system.

I too look at a MicroMite / PicoMite as an embedded system, but am amazed at what can be done with some of the extended functions we now have access to with HDMI / VGA graphics and so many LCD displays.

On top of this we have an enormous amount of device support without resorting to libraries etc.

Whilst my own abilities as a programmer are pretty poor, trying out the new commands / functions / systems as they are added and reading the posts of how others are using them has taught me a lot, and inspired many ideas, whether I will ever use some of it is another matter.

Also only my 5c

Regards,
Lyle.

Martin H.

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Joined: 04/06/2022
Location: Germany
Posts: 1354

Posted: 02:38pm 10 Feb 2026

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The freely scalable sprites certainly have their appeal.
They would also be useful in other applications (such as Leon's Outrun port etc.)
ym2c
Martin

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gadgetjack
Senior Member

Joined: 15/07/2016
Location: United States
Posts: 185

Posted: 04:53pm 10 Feb 2026

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Just putting in my 2 cents worth. I understand all the ones using this for control projects , I did that for years till I retired. But the graphics capabilities of this little machine have caught my eye from the beginning. I have followed now for a few years after finding this site and really enjoy the games and demo programs so many capable people on here write. I tip my hat to all of you. I really would like to see the RAY functions added , they would not eat that much memory up. Most designs have SD cards anyway for saving your code to. I vote for the RAY functions.
Jack

bfwolf
Senior Member

Joined: 03/01/2025
Location: Germany
Posts: 159

Posted: 09:20pm 10 Feb 2026

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The discussion here about whether "ray casting" should be done via built-in commands, CSUBs, or directly in MMBasic, has once again shown me how beneficial it would be if MMBasic supported DLLs and their subs and functions. This would allow for the elegant and efficient implementation of highly specialized tasks suitable only for a selected user group and very specific use cases. And the MMBasic core wouldn't grow every time.

bfwolf.

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10953

Posted: 10:23pm 10 Feb 2026

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Quote has once again shown me how beneficial it would be if MMBasic supported DLLs and their subs and functions.

Can't be done - won't be done

homa

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Joined: 05/11/2021
Location: Germany
Posts: 538

Posted: 03:12pm 14 Feb 2026

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@Martin H. that's impressive.

@LeoNicolas thank you for the great explanatory video. I only knew the solution with the individual steps.

@matherp Peter, is it possible to get the graphics for your example? I can't find them anywhere. I'm currently testing the version PicoMiteHDMI MMBasic USB RP2350A Edition V6.02.01b2 - i

it

Matthias
Edited 2026-02-15 01:14 by homa

Martin H.

Guru

Joined: 04/06/2022
Location: Germany
Posts: 1354

Posted: 05:52pm 14 Feb 2026

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I have optimised this a little to keep the calculations within the DDA loop as low as possible.

' Raycaster 2 in MMBasic, DDA method (Digital Differential Analyser)
'V0.5
mmb4w=0
CLS
If mmb4w Then
MODE -7 :CLS RGB(cyan)
PAGE WRITE 1
Else
MODE 2: CLS RGB(cyan)
FRAMEBUFFER create:FRAMEBUFFER write f
End If
CLS
mapS=64:mapy=24:mapx=24
' --- Labyrinth Definition ---
mapW = 57:mapH = 51
Dim integer m(mapW, mapH),Col%(3,2),cll
Restore MapData1
For y = 0 To mapH-1 :Read k$:k$=k$+"1"
For x=0 To Len(k$):m(x, y)=Val(Mid$(k$,x+1,1)):Next :Next

' --- Player Setup ---
px = 26.5 : py = 45.5
dx = 1 : dy = 0.5
planeX = 0 : planeY = 0.66
moveSpeed = 0.3
rotSpeed = 0.1
buffer = 0.2
' --- Grafic Setup ---
resStep = 3
scrW = MM.HRES*.75
scrH = MM.VRES*.75
' Flag to force the first frame
needsRedraw = 1
invScrW = 2 / scrW
halfScrH = scrH / 2
colWallA = RGB(GREEN)
colWallB = RGB(0,128,0)
colSky = RGB(0,128,255)
colFloor = RGB(0,0,0)
Do
' Only paint when something has changed
If needsRedraw = 1 Then
tt=Timer
' Ceiling and floor
Box 0, 0, scrW, halfScrH, 0, colSky, colSky
Box 0, halfScrH, scrW, halfScrH, 0, colFloor, colFloor
'DDA
For x = 0 To scrW - 1 Step resStep
cameraX = x * invScrW - 1
rayDx = dx + planeX * cameraX
rayDy = dy + planeY * cameraX
mx = Int(px) : my = Int(py)
If rayDx = 0 Then
dDx = 1e30
Else
invRayDx = 1 / rayDx: dDx = Abs(invRayDx)
End If
If rayDy = 0 Then
dDy = 1e30
Else
invRayDy = 1 / rayDy :dDy = Abs(invRayDy)
End If

If rayDx < 0 Then
stepX = -1 : sdX = (px - mx) * dDx
Else
stepX = 1 : sdX = (mx + 1 - px) * dDx
End If
If rayDy < 0 Then
stepY = -1 : sdY = (py - my) * dDy
Else
stepY = 1 : sdY = (my + 1 - py) * dDy
End If
hit = 0
Do While hit = 0
If sdX < sdY Then
Inc sdX,dDx:Inc mx,stepX : side = 0
Else
Inc sdY,dDy:Inc my,stepY : side = 1
End If
If m(mx, my)>0 Then hit = 1
Loop
cll=m(mx, my)
If side = 0 Then pDist = (sdX - dDx) Else pDist = (sdY - dDy)
If pDist < 0.1 Then pDist = 0.1

lH = Int(scrH / pDist)
yS = halfScrH - (lH/2)
wallCol = colWallA
If side = 1 Then wallCol = colWallB
Box x, yS, resStep, lH, , wallCol,wallCol
Next x
If mmb4w Then
PAGE WRITE 0:Blit 0,0,0,0,scrW,scrH,1
Text scrW,0,"X="+Str$(Int(px))+" "
Text scrW,12,"Y="+Str$(Int(py))+" "
Text scrW,24,Str$(Timer-tt)+" ":tt=Timer
PAGE WRITE 1
Else
FRAMEBUFFER write n
Text scrW,0,"X="+Str$(Int(px))+" "
Text scrW,12,"Y="+Str$(Int(py))+" "
Text scrW,24,Str$(Timer-tt)+" ":tt=Timer
FRAMEBUFFER write f
Blit framebuffer F,N,0,0,0,0,scrW,scrH
End If
needsRedraw = 0 ' Reset Redraw Flag
End If
' Wait for button (does not block, but checks efficiently)
k$ = UCase$(Inkey$)
Do :Loop Until Inkey$=""
If k$ <> "" Then
' Enable redraw when a movement key is pressed
If Instr("WASD", k$) > 0 Then needsRedraw = 1
Select Case k$
Case "W"
If m(Int(px + dx * buffer), Int(py)) = 0 Then px = px + dx * moveSpeed
If m(Int(px), Int(py + dy * buffer)) = 0 Then py = py + dy * moveSpeed
Case "S"
If m(Int(px - dx * buffer), Int(py)) = 0 Then px = px - dx * moveSpeed
If m(Int(px), Int(py - dy * buffer)) = 0 Then py = py - dy * moveSpeed
Case "D"
oldDx = dx : dx = dx * Cos(rotSpeed) - dy * Sin(rotSpeed)
dy = oldDx * Sin(rotSpeed) + dy * Cos(rotSpeed)
oldPx = planeX : planeX = planeX * Cos(rotSpeed) - planeY * Sin(rotSpeed)
planeY = oldPx * Sin(rotSpeed) + planeY * Cos(rotSpeed)
Case "A"
oldDx = dx : dx = dx * Cos(-rotSpeed) - dy * Sin(-rotSpeed)
dy = oldDx * Sin(-rotSpeed) + dy * Cos(-rotSpeed)
oldPx = planeX : planeX = planeX * Cos(-rotSpeed) - planeY * Sin(-rotSpeed)
planeY = oldPx * Sin(-rotSpeed) + planeY * Cos(-rotSpeed)
End Select
End If
Loop Until k$ = Chr$(27)
If mmb4w Then PAGE WRITE 0
MapData1: '
Data "11111111111111111111111133333333333331111111111111111111"
Data "11111111111111111111111133333333333331111111111111111111"
Data "11111111111111111111111130000000000333331111111111111111"
Data "11111000011111111111111130000000000333331111111111111111"
Data "11111000011111110000000000000000000300331111111111111111"
Data "11111000011111110000000030000000000300331111111111111111"
Data "11111110111111110011111130000000000333331111111111111111"
Data "11111000000001110011111130000000000333331111111111111111"
Data "11111000000001110011111133333003333331111111111111111111"
Data "11111000000001000000111133333003333331111111111111111111"
Data "11111000000000000000111111333003333331111111111111111111"
Data "11111000000001000000111111333003311111111111111111111111"
Data "11111000000001111111111333333003333111111111111111111111"
Data "10011111001111111111111333333003333111111111111111111111"
Data "10011111001111111111111300000000333111111111111111111111"
Data "11011111001111111111111300333003333111111111111111111111"
Data "10011111001111111111111300333003333111111111111111111111"
Data "10000000001111111111111300333003333111111111111111111111"
Data "10010000001111111111111333333003311111111111111111111111"
Data "10011111111111111111111111113003111111111111122222222222"
Data "10011000000001111111111111110000111111111111122222222222"
Data "10011000000001111111111300000000000031222222222000000022"
Data "10011000000001111111111000000000000002222222222000000022"
Data "10001000000001111111111000000000000000000000002000000022"
Data "10000000000001111111111000000000000000000000000000000022"
Data "10001000000001111111111000000000000002000000222000000022"
Data "10011000000001111111111000000000000001122002222000000022"
Data "10011000000001111111111111110000111111122002222000000022"
Data "10011111011111111111111111112202211111122002222222222222"
Data "10011111001111111111111111122002211111122002222222222222"
Data "10011111001111111111111111122002211111122002222222222222"
Data "10010001001111111111111111122002211111122002222222222211"
Data "10000001001111111111111111122002211111122002222020022211"
Data "10011111001111111111111111122002211111122000000000000211"
Data "10011111001111111111111111122002211111122000000000002211"
Data "10000000000000010000011111122002211111122022002020220211"
Data "10000000000000000000000111122002211111122222222222222211"
Data "10000000000000010000011111122002211111111111111111111111"
Data "11111111111111110111111122222002222221111111111111111111"
Data "11111111110010000111111222222202222221111111111111111111"
Data "11111111110000011111111200000000000021111111111111111111"
Data "11111111111011111111111200002002000021111111111111111111"
Data "11111111111001111111111200002002000021111111111111111111"
Data "11111111111001111111111222222002222221111111111111111111"
Data "11111111111111111111111200002002000021111111111111111111"
Data "11111111111111111111111200000000000021111111111111111111"
Data "11111111111111111111111200002002000021111111111111111111"
Data "11111111111111111111111222222002222221111111111111111111"
Data "11111111111111111111111200000000000021111111111111111111"
Data "11111111111111111111111200000000000021111111111111111111"
Data "11111111111111111111111222222222222221111111111111111111"

I have revised the map again. Now you get different values when you hit a wall. Here, I have planned to colour different areas differently (as in Wolf3d), which should help with orientation. The value found is stored in 'cll' but not yet evaluated.
Have Fun
Cheers
Martin

'no comment

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