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Martin H.

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Joined: 04/06/2022
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Posted: 03:55pm 08 Feb 2026

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DDA method (Digital Differential Analyser).Much faster than my previous attempts.

' Raycaster 2 in MMBasic, DDA method (Digital Differential Analyser)
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 ---
Dim mapW = 57
Dim mapH = 51
Dim m(mapW, mapH)
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
'For y = 0 To mapH-1 : For x = 0 To mapW-1 : Read m(x, y) : Next x : Next y
' --- Player Setup ---
px = 26.5 : py = 45.5
dx = 1.0 : dy = 0.5
planeX = 0.0 : planeY = 0.66
moveSpeed = 0.2
rotSpeed = 0.1
buffer = 0.2
' --- Grafic Setup ---
resStep = 2
scrW = MM.HRES*.75
scrH = MM.VRES*.75

' Flag to force the first frame
needsRedraw = 1

Do
' Only paint when something has changed
If needsRedraw = 1 Then
' Ceiling and floor
Box 0, 0, scrW, scrH/2, 0, RGB(0,128,255), RGB(0,128,255)
Box 0, scrH/2, scrW, scrH/2, 0, RGB(255,128,0), RGB(255,128,0)
'DDA
For x = 0 To scrW - 1 Step resStep
cameraX = 2 * x / scrW - 1
rayDx = dx + planeX * cameraX
rayDy = dy + planeY * cameraX
mx = Int(px) : my = Int(py)

If rayDx = 0 Then dDx = 1e30 Else dDx = Abs(1 / rayDx)
If rayDy = 0 Then dDy = 1e30 Else dDy = Abs(1 / rayDy)

If rayDx < 0 Then
stepX = -1 : sdX = (px - mx) * dDx
Else
stepX = 1 : sdX = (mx + 1.0 - px) * dDx
End If
If rayDy < 0 Then
stepY = -1 : sdY = (py - my) * dDy
Else
stepY = 1 : sdY = (my + 1.0 - py) * dDy
End If
hit = 0
Do While hit = 0
If sdX < sdY Then
sdX = sdX + dDx : mx = mx + stepX : side = 0
Else
sdY = sdY + dDy : my = my + stepY : side = 1
EndIf
If m(mx, my) > 0 Then hit = 1
Loop
If side = 0 Then pDist = (sdX - dDx) Else pDist = (sdY - dDy)
If pDist < 0.1 Then pDist = 0.1

lH = Int(scrH / pDist)
yS = (scrH / 2) - (lH / 2)
wallCol = RGB(GREEN)
If side = 1 Then wallCol = RGB(0, 128, 0)
Box x, yS, resStep, lH, , wallCol
Next x
If mmb4w Then
PAGE WRITE 0:Blit 0,0,0,0,scrW,scrH,1:PAGE WRITE 1
Else
FRAMEBUFFER write n
Text 290,0,"X="+Str$(Int(px))+" "
Text 290,12,"Y="+Str$(Int(py))+" "
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$(Inkey$)
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 "11111111111111111111111111111111111111111111111111111111"
Data "11111111111111111111111110000000000111111111111111111111"
Data "11111000011111111010111110000000000111111111111111111111"
Data "11111000011111100000000000000000000100111111111111111111"
Data "11111000011111100000000010000000000100111111111111111111"
Data "11111011111111110011111110000000000111111111111111111111"
Data "11111000000000110011111110000000000111111111111111111111"
Data "11111000000001110010111111111001111111111111111111111111"
Data "11111000000000000000111111111001111111111111111111111111"
Data "11111000000000000000111111111001111111111111111111111111"
Data "10000000000001000000111111111001111111111111111111111111"
Data "11111000000001111111111111111001111111111111111111111111"
Data "10000011111101111111111111111001111111111111111111111111"
Data "10011111001111111111111100000000011111111111111111111111"
Data "10111111001111111111111100111001111111111111111111111111"
Data "10011111001111111111111100111001111111111111111111111111"
Data "10000001001111111111111100111001111111111111111111111111"
Data "10000011001111111111111111111001111111111111111111111111"
Data "10010101111011111111111111111001010100111111101111110111"
Data "10011000000001111111111101110000111011111111101000000011"
Data "10010000000001111111111100000000000010010001001000000000"
Data "10011000000001111111111000000000000001111111101000000011"
Data "10001000000000111111111000000000000000000000001000000000"
Data "10001000000001111111111000000000000000000000000000000001"
Data "10001000000001111111111000000000000001000000001000000000"
Data "10011000000001111111111000000000000000111001111000000001"
Data "10011000000001111111111111010000101111110000101000000011"
Data "10011111011011111111111111111101110100110001001011110101"
Data "10001111001111111111111111111000111111111000100110010001"
Data "10011111001111111111111111110000111111110001001000100100"
Data "10010001001111111111111111111000111111111000111111111111"
Data "10000001001111111111111111110001111111110001001000010111"
Data "10011111001111101111111111111001111111111000000000000111"
Data "10001010001111011110101111110001011111110000000000001111"
Data "10000000000000000000011111111000111111111011001010110111"
Data "10000000000000000000000111110000111111111111111111111111"
Data "10000000000000010000011111110001111111111111111111111111"
Data "11101110111101111111111111111000111111111111111111111111"
Data "11111111110010000111111111101101111011111111111111111111"
Data "11111111110000011111111100000000000011111111111111111111"
Data "11111111111011111111111100001001000001111111111111111111"
Data "11111111111001111111111000000000000011111111111111111111"
Data "11111111111001111111111111111001111111111111111111111111"
Data "11111111111111111111111100001001000011111111111111111111"
Data "11111111111111111111111100000000000001111111111111111111"
Data "11111111111111111111111100001001000011111111111111111111"
Data "11111111111111111111111111111001111111111111111111111111"
Data "11111111111111111111111100000000000011111111111111111111"
Data "11111111111111111111111100000000000011111111111111111111"
Data "11111111111111111111111100101010001011111111111111111111"
Data "11111111111111111111111111111111111111111111111111111111"

This is just a basic framework. Feel free to change and expand it.
Cheers
Martin

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LeoNicolas

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Joined: 07/10/2020
Location: Canada
Posts: 560

Posted: 05:10pm 08 Feb 2026

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Nice job Martin

For anyone that wants to know more about DDA and ray casting

https://www.youtube.com/watch?v=NbSee-XM7WA

Martin H.

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Joined: 04/06/2022
Location: Germany
Posts: 1350

Posted: 05:25pm 08 Feb 2026

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I forgot to mention,
the keys are ‘AD WS’ and ESC to quit.

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Peter63
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Joined: 28/07/2017
Location: Sweden
Posts: 117

Posted: 01:28am 09 Feb 2026

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Hello Martin

I tried it on PicoMiteHDMIUSB V6.02.00RC6 and it works perfectly.

/Peter63

Martin H.

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Joined: 04/06/2022
Location: Germany
Posts: 1350

Posted: 06:47am 09 Feb 2026

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Peter63 said Hello Martin

I tried it on PicoMiteHDMIUSB V6.02.00RC6 and it works perfectly.

/Peter63

Hi Peter,
Thanks for the feedback. I also tried it on Pico2 with HDMI (Try MODE 3). It should also run on CMM2 and MMBasic for Windows if you set mmb4w=1 at the start of the Programm.

Cheers
Martin
Edited 2026-02-09 16:49 by Martin H.

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Volhout
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Location: Netherlands
Posts: 5671

Posted: 07:51am 09 Feb 2026

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Hi Martin,

Works nice (RP2040 VGA), but requires quite a lot of math. So it is somewhat slow.
Maybe a lot better on 2350.

Now I look at what you are planning to do, could you not make use of the 3D DRAW commands in MMBasic. I am not sure the 3D DRAW routines Peter implemented can handle the whole map, but they certainly could handle the visible part of the map (they also can rotate a multiface football).
If you place your camera inside the football (inside your maze) this could work ?

Regards,

Volhout

EDIT: Martin, I tried to speed things up by changing "resStep" from 2 to 5, but that corrupts the drawing. Change line 78 into adding "wallCol" as fill color.
Edited 2026-02-09 18:42 by Volhout

PicomiteVGA PETSCII ROBOTS

Martin H.

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Joined: 04/06/2022
Location: Germany
Posts: 1350

Posted: 08:46am 09 Feb 2026

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Volhout said Hi Martin,

Works nice (RP2040 VGA), but requires quite a lot of math. So it is somewhat slow.
Maybe a lot better on 2350.

Now I look at what you are planning to do, could you not make use of the 3D DRAW commands in MMBasic. I am not sure the 3D DRAW routines Peter implemented can handle the whole map, but they certainly could handle the visible part of the map (they also can rotate a multiface football).
If you place your camera inside the football (inside your maze) this could work ?

Regards,

Volhout

Volhout,
You can speed it up by increasing resStep = 2 to resStep = 4 and changing the box command before NEXT X to ‘Box x, yS, resStep, lH, , wallCol, wallCol’.
This halves the number of calculations required, but also the x resolution.

It could be, of course, possible to use the 3D DRAW routines, but this is a completely different approach to ray casting. To do this, the field of view would have to be vectorised and converted into 3D models. This is certainly possible, but I'm not sure if it would be faster in the end.
The initial aim here was to limit the raycast calculations to simple/fast calculations(certainly still room for improvement). I have no experience with the 3D DRAW routines, but I am open to being convinced.
Cheers
Martin
Edited 2026-02-09 19:02 by Martin H.

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thwill

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Joined: 16/09/2019
Location: United Kingdom
Posts: 4339

Posted: 10:48am 09 Feb 2026

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A screenshot for those who are interested, but not enough to crank up the 'Mite:

Generated by MMB4L running under WSL2 on Windows whilst simulating a PicoMite

.

Best wishes,

Tom
Edited 2026-02-09 20:49 by thwill

MMBasic for Linux, Game*Mite, CMM2 Welcome Tape, Creaky old text adventures

Martin H.

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Posts: 1350

Posted: 03:53pm 09 Feb 2026

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thwill said
Generated by MMB4L running under WSL2 on Windows whilst simulating a PicoMite

.

Best wishes,

Tom

Yes, that sounds reasonable.

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matherp
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Posted: 04:38pm 09 Feb 2026

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How about this ? - -worth including in the RP2350 firmware?

Manual:

Raycaster_User_Manual.pdf

Example code:

Quote ' ============================================================
' Raycaster Demo for PicoMite MMBasic (RP2350)
' Continuous auto-play loop with animated sliding door
' Demonstrates: RAY MOVE, RAY TURN, RAY CELL, RAY CAST,
' RAY SPRITE, RAY MINIMAP, RAY DOOR
' Press ESC at any time to quit
' ============================================================
Option EXPLICIT
MODE 2
CLS

' ---- Map dimensions ----
Const MAP_W = 57
Const MAP_H = 51
Const FOV = 66

' ---- Start position ----
Const START_X = 25.5
Const START_Y = 23.5
Const START_A = 0

' ---- Variables ----
Dim INTEGER x%, y%, i%, cx%, cy%, door_x%, door_y%, door_wall%
Dim k$
Dim FLOAT moveSpeed, rotSpeed

moveSpeed = 0.2
rotSpeed = 5.625 ' exactly 90 degrees per 16 steps

' ---- Door animation state ----
Dim FLOAT door_offset!, door_target!, door_step!
Dim INTEGER door_animating%
door_step! = 0.1 ' offset change per frame (10 frames to fully open/close)

' ---- Read map data into 1D array ----
Dim INTEGER world%(MAP_W * MAP_H - 1)
Restore MapData1
For y% = 0 To MAP_H - 1
Read k$
k$ = k$ + "1"
For x% = 0 To MAP_W - 1
world%(y% * MAP_W + x%) = Val(Mid$(k$, x% + 1, 1))
Next x%
Next y%

' Vary wall types
For y% = 0 To MAP_H - 1
For x% = 0 To MAP_W - 1
If world%(y% * MAP_W + x%) > 0 Then
world%(y% * MAP_W + x%) = ((x% + y%) Mod 1) + 5
EndIf
Next x%
Next y%

' ---- Set up framebuffer & raycaster ----
FRAMEBUFFER CREATE
FRAMEBUFFER WRITE F
Ray MAP MAP_W, MAP_H, world%()
Ray COLOUR 12, 3, 8, 1, 1, 3

' ---- Load 4bpp RGB121 sprite images via SPRITE LOADARRAY ----
Const C_BLK = &h000000 ' index 0 - transparent
Const C_RED = &hFF0000 ' index 8
Const C_GRN = &h00FF00 ' index 6
Const C_BLU = &h0000FF ' index 1
Const C_YEL = &hFFFF00 ' index 14
Const C_CYN = &h00FFFF ' index 7
Const C_MAG = &hFF00FF ' index 9
Const C_WHT = &hFFFFFF ' index 15

Sprite SET TRANSPARENT 0 ' index 0 (black) is transparent
Dim INTEGER spr%(63) ' reusable 8x8 pixel array

Sprite loadpng 1,"char.png",-2,1
Sprite LOADpng 2, "char2.png",-2,1
Sprite LOADpng 3, "char3.png",-2,1
Sprite LOADpng 4, "char4.png",-2,1

' Sprite 5: White ring on black background
For i% = 0 To 63: spr%(i%) = C_BLK: Next i%
For i% = 2 To 5: spr%(0 * 8 + i%) = C_WHT: spr%(7 * 8 + i%) = C_WHT: Next i%
For i% = 2 To 5: spr%(i% * 8 + 0) = C_WHT: spr%(i% * 8 + 7) = C_WHT: Next i%
spr%(1 * 8 + 1) = C_WHT: spr%(1 * 8 + 6) = C_WHT
spr%(6 * 8 + 1) = C_WHT: spr%(6 * 8 + 6) = C_WHT
Sprite LOADARRAY 5, 8, 8, spr%()

' ---- Place billboard sprites in the open area ----
' RAY SPRITE id, spritenum, x!, y!
Ray SPRITE 0, 1, 32.5, 23.5 ' Red cross, ahead east
Ray SPRITE 1, 2, 32.5, 24.5 ' Yellow diamond, southeast
Ray SPRITE 2, 3, 26.5, 24.5 ' Green stripes, southwest
Ray SPRITE 3, 4, 26.5, 23.5 ' Checkerboard, behind west
Ray SPRITE 4, 5, 29.5, 22.5 ' White ring, just north

' ---- Pre-programmed input sequence (round trip) ----
Dim seq$
seq$ = "P5W22P3O1P10W15P5D16W5P5W5D16W30D16W5P5W5P5D16W15P3C1P10A16W5P5D32W5D16W22D16D16P5"

Dim INTEGER curpos%, reps%, r%
Dim cmd$

' ============================================================
' MAIN LOOP - runs continuously until ESC
' ============================================================
Do
' ---- Reset camera to start position ----
Ray CAMERA START_X, START_Y, START_A, FOV

' ---- Rebuild door wall (north-south at x=30, y=19..24) ----
Ray CELL 30, 19, 3
Ray CELL 30, 20, 3
Ray CELL 30, 21, 3
Ray CELL 30, 22, 3
Ray CELL 30, 23, 31 ' door (wall type >= 16 = brown/yellow)
Ray CELL 30, 24, 3

' ---- Reset door animation state ----
door_offset! = 0.0
door_target! = 0.0
door_animating% = 0
door_x% = 30: door_y% = 23: door_wall% = 31
Ray DOOR CLEAR

' ---- Execute the sequence ----
curpos% = 1
Do While curpos% <= Len(seq$)
cmd$ = Mid$(seq$, curpos%, 1)
curpos% = curpos% + 1

' Read repeat count
reps% = 0
Do While curpos% <= Len(seq$)
k$ = Mid$(seq$, curpos%, 1)
If k$ >= "0" And k$ <= "9" Then
reps% = reps% * 10 + Val(k$)
curpos% = curpos% + 1
Else
Exit Do
EndIf
Loop
If reps% = 0 Then reps% = 1

' Execute reps% times
For r% = 1 To reps%
k$ = Inkey$
If k$ = Chr$(27) Then GoTo Done

Select Case cmd$
Case "W": Ray MOVE moveSpeed
Case "S": Ray MOVE -moveSpeed
Case "A": Ray TURN -rotSpeed
Case "D": Ray TURN rotSpeed
Case "O"
' Start door open animation
door_target! = 1.0
door_animating% = 1
Ray DOOR door_x%, door_y%, door_offset!
Case "C"
' Start door close animation
door_target! = 0.0
door_animating% = 1
Case "P"
' Pause = render only, no movement
End Select

' ---- Update door animation every frame ----
If door_animating% Then
Pause 50
If door_target! > door_offset! Then
door_offset! = door_offset! + door_step!
If door_offset! >= door_target! Then
door_offset! = door_target!
door_animating% = 0
EndIf
ElseIf door_target! < door_offset! Then
door_offset! = door_offset! - door_step!
If door_offset! <= door_target! Then
door_offset! = door_target!
door_animating% = 0
If door_offset! <= 0.0 Then
Ray DOOR CLOSE door_x%, door_y%
EndIf
EndIf
Else
door_animating% = 0
EndIf
If door_offset! > 0.0 Then
Ray DOOR door_x%, door_y%, door_offset!
EndIf
EndIf

' ---- Render frame ----
Ray RENDER
Ray MINIMAP 2, 2, 48
Line MM.HRES\2 - 4, MM.VRES\2, MM.HRES\2 + 4, MM.VRES\2,, RGB(WHITE)
Line MM.HRES\2, MM.VRES\2 - 4, MM.HRES\2, MM.VRES\2 + 4,, RGB(WHITE)
FRAMEBUFFER COPY F, N
Pause 30
Next r%
Loop

' Brief pause before restarting the loop
Pause 500
Loop

Done:
Ray CLOSE
FRAMEBUFFER CLOSE
CLS
Print "Raycaster demo ended."
End

MapData1:
Data "11111111111111111111111111111111111111111111111111111111"
Data "11111111111111111111111110000000000111111111111111111111"
Data "11111000011111111010111110000000000111111111111111111111"
Data "11111000011111100000000000000000000100111111111111111111"
Data "11111000011111100000000010000000000100111111111111111111"
Data "11111011111111110011111110000000000111111111111111111111"
Data "11111000000000110011111110000000000111111111111111111111"
Data "11111000000001110010111111111001111111111111111111111111"
Data "11111000000000000000111111111001111111111111111111111111"
Data "11111000000000000000111111111001111111111111111111111111"
Data "10000000000001000000111111111001111111111111111111111111"
Data "11111000000001111111111111111001111111111111111111111111"
Data "10000011111101111111111111111001111111111111111111111111"
Data "10011111001111111111111100000000011111111111111111111111"
Data "10111111001111111111111100111001111111111111111111111111"
Data "10011111001111111111111100111001111111111111111111111111"
Data "10000001001111111111111100111001111111111111111111111111"
Data "10000011001111111111111111111001111111111111111111111111"
Data "10010101111011111111111111111001010100111111101111110111"
Data "10011000000001111111111101110000111011111111101000000011"
Data "10010000000001111111111100000000000010010001001000000000"
Data "10011000000001111111111000000000000001111111101000000011"
Data "10001000000000111111111000000000000000000000001000000000"
Data "10001000000001111111111000000000000000000000000000000001"
Data "10001000000001111111111000000000000001000000001000000000"
Data "10011000000001111111111000000000000000111001111000000001"
Data "10011000000001111111111111010000101111110000101000000011"
Data "10011111011011111111111111111101110100110001001011110101"
Data "10001111001111111111111111111000111111111000100110010001"
Data "10011111001111111111111111110000111111110001001000100100"
Data "10010001001111111111111111111000111111111000111111111111"
Data "10000001001111111111111111110001111111110001001000010111"
Data "10011111001111101111111111111001111111111000000000000111"
Data "10001010001111011110101111110001011111110000000000001111"
Data "10000000000000000000011111111000111111111011001010110111"
Data "10000000000000000000000111110000111111111111111111111111"
Data "10000000000000010000011111110001111111111111111111111111"
Data "11101110111101111111111111111000111111111111111111111111"
Data "11111111110010000111111111101101111011111111111111111111"
Data "11111111110000011111111100000000000011111111111111111111"
Data "11111111111011111111111100001001000001111111111111111111"
Data "11111111111001111111111000000000000011111111111111111111"
Data "11111111111001111111111111111001111111111111111111111111"
Data "11111111111111111111111100001001000011111111111111111111"
Data "11111111111111111111111100000000000001111111111111111111"
Data "11111111111111111111111100001001000011111111111111111111"
Data "11111111111111111111111111111001111111111111111111111111"
Data "11111111111111111111111100000000000011111111111111111111"
Data "11111111111111111111111100000000000011111111111111111111"
Data "11111111111111111111111100101010001011111111111111111111"
Data "11111111111111111111111111111111111111111111111111111111"

thwill

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Joined: 16/09/2019
Location: United Kingdom
Posts: 4339

Posted: 05:13pm 09 Feb 2026

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Hi Peter,

It's technically impressive, but in my view it's unnecessary "bloat", a piece of functionality that perhaps one person might used to write a Wolfenstein knock-off.

IMO it would be better not to include it and let that one person "show their chops" and get the achievement of doing it in MMBasic alone (might not be possible on the PicoMite) or writing some CSUBs.

YMMV,

Tom
Edited 2026-02-10 03:27 by thwill

MMBasic for Linux, Game*Mite, CMM2 Welcome Tape, Creaky old text adventures

phil99

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Joined: 11/02/2018
Location: Australia
Posts: 2991

Posted: 08:50pm 09 Feb 2026

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On this forum there appear to be three main uses for MMBasic, games, retro computing and embedded controllers. The CMM2-G2 has the power to be perfect for the first two.
MMB4W and MMB4L extend that to PCs and where portability is needed to notebooks.

For embedded controllers the size, price and power consumption make those platforms unattractive leaving mainly the PicoMite and MicroMite to do the job.

As there are fewer options for embedded controllers my preference would be to leave as much room as practical for that on the Pico non HDMI / VGA / USB versions.

gadgetjack
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Joined: 15/07/2016
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Posts: 184

Posted: 11:50pm 09 Feb 2026

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Ok, I am hooked. Where do I get the code for that??? Can it be added as a library or what?

Turbo46

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Joined: 24/12/2017
Location: Australia
Posts: 1661

Posted: 05:13am 10 Feb 2026

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Very impressive but I also wonder how many people would actually make use of it. I feel that already too much has been done to cater for too few people and too many different boards. I would love to see some things come out as Csubs so that only those who want or need them can add the.

There is a bewildering number of options. I was gobsmacked to see that in the latest manual there are 10 pages of options!

I don't expect that my opinion will carry any weight at all but there it is for what it's worth.

Bill

Keep safe. Live long and prosper.

Volhout
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Posted: 07:16am 10 Feb 2026

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All,

For some who may have followed the discussions, Peter is putting effort into bringing Mauro Xavier back on board. Mauro is a skilled game designer, that provided several top games for CMM2. Peter plans to send him a picomite HDMI and these RAY commands may be all that is needed for Mauro to port his version of "INTO THE DARK" to picomite.

Invitation

I do realize that Peters implementation trampling over Martin.H's work. But this could be coincidental. Peter could have started with these implementation much earlier. At time he invited Mauro. Writing the code (10+ commands), the demo, the manual, all in few hours ?

And this RAY command will not exist in RP2040. So Martin.H's work is valuable to me... call me "mister_2040"..

Volhout

PicomiteVGA PETSCII ROBOTS

Mixtel90

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Posted: 07:42am 10 Feb 2026

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CSUBs aren't always the answer as, at least in the past, they don't seem to have remained compatible with MMBasic upgrades. They have the advantage of speed though - and that is also the argument for having the routines built-in. This is pretty intensive stuff. I considered suggesting putting it into Library routines but that might be too slow.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

Martin H.

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Location: Germany
Posts: 1350

Posted: 08:51am 10 Feb 2026

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thwill said IMO it would be better not to include it and let that one person "show their chops" and get the achievement of doing it in MMBasic alone (might not be possible on the PicoMite) or writing some CSUBs.

Very well explained, Tom.
I wrote this Code to show how it can be done at a reasonable speed on the Pico in Basic. I'm not the one writing a Wolfenstein Clone, but I'm happy to provide the tools for it. In my opinion, extending Basic doesn't make sense due to the very specific task, but implementing it as CSUB would be appropriate.
Cheers
Martin

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matherp
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Posted: 09:05am 10 Feb 2026

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We should get over the concept that this sort of thing can be done in a CSUB. They are limited in what they can do and don't have full access to MMBasic internals. Moreover, they are extremely difficult to write with no real debugging possible other than go/no-go (often crash).
Adding commands to MMbasic has almost no overhead other than possibly increasing the size of the image which in turn reduces the amount of the A: drive available. In fact, as the image has to increase in 16K chunks the implementation above had NO impact on the RP2350 VGA firmware image size.
My approach to all these "niche" commands is now to only reference their existence in the main manual and produce a separate manual for the command - STAR, SPRITE, STEPPER etc. Thus the impact on anyone who doesn't want to use them is negligible. If we take the stepper command as an example, this categorically couldn't be done as a CSUB, nor could it be done in Basic with adequate speed. For a user who wants to drive a stepper properly with a PicoMite it provides a solution. For those who don't it has zero impact.

thwill

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Posted: 09:20am 10 Feb 2026

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For some time my base opinion on MMBasic development is that nobody is paying the piper so he gets to play his own tune - i.e. Peter can do what he likes ;-)

However if it were my project (it isn't) and I had the time (I don't) then ...

matherp said We should get over the concept that this sort of thing can be done in a CSUB. They are limited in what they can do and don't have full access to MMBasic internals. Moreover, they are extremely difficult to write with no real debugging possible other than go/no-go (often crash).

This is where I think the most bangs for the buck in terms of taking MMBasic to the next level now lie. Proper CSUB (and CFUNCTION) documentation and a documented and where necessary extended API by which CSUBs can access MMBasic internals so it isn't an ever extending monolith.

However I'm not a micro-controller programmer I'm a PC app developer so I might well be talking out of my derrière.

Have a pleasant Tuesday folks,

Tom
Edited 2026-02-10 19:21 by thwill

MMBasic for Linux, Game*Mite, CMM2 Welcome Tape, Creaky old text adventures

Mixtel90

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Posted: 10:16am 10 Feb 2026

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TBH, Tom, I don't find that "Peter can do what he likes" is such a terrible option. :) I don't even mind losing chunks of A: drive on the RP2350 very much. It's a bit more of a problem on the RP2040 but the new commands aren't generally applicable to that anyway.

IMHO retro-fitting a full implementation of CSUB/CFUNCTION with API would be virtually impossible without a major re-write of almost all of the code. It was probably designed to be monolithic, not to be extendable like that and I suspect that many low level (and maybe not so low) routines are shared in order to keep the code compact. Even if it was available how useful would it *really* be on a microcontroller? Be honest. This isn't even a tiny SBC like a Raspberry Pi. I don't personally think that CSUBs and CFUNCTIONs are a great idea anyway. Yes, they can do some things very fast but they make the code unreadable, virtually impossible to understand and mostly unsupportable by anyone other than the original writer. It's a lot to lose from BASIC in the interests of speed.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

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