TheBackShed.com

Forum Index : Microcontroller and PC projects : Blit RESIZE abused ;-)

Author

Message

Martin H.

Guru

Joined: 04/06/2022
Location: Germany
Posts: 1447

Posted: 01:11pm 09 Mar 2026

Copy link to clipboard

Print this post

For PicoMite V6.02.01 RC 1 or later
Here is an example of using BLIT RESIZE somewhat outside its intended use.
BLIT RESIZE draws a floor similar to the game Ballblazer. At this speed, the simultaneous view for the second player/NPC would also not be a problem.
Movement is again controlled using the WS AD keys.

Dim integer mmb4w
Dim integer Bcl(16,160),speed=3
phase
' --- Initialisierung ---
CLS
' --- Init_Graphics: Setup 320x240 Resolution, Layer-Buffer).
If MM.DEVICE$ = "MMBasic for Windows" Then mmb4w = 1
If mmb4w Then
MODE 7
PAGE WRITE 1
CLS
Else
'Pico
MODE 2
FRAMEBUFFER create : FRAMEBUFFER write f
End If
' 2. Z-Table
Dim integer x,y, z_dist(38)
For y = 0 To 37
Read scal:z_dist(y)=16+(scal/4)
Next y

CLS 'clear FRAMEBUFFER
Dim integer hh=120,hw=160,f,n,w
Dim integer c1=RGB(0,180,0),c2=RGB(White)
Dim Integer sky=RGB(0,85,255),sky1=RGB(0,170,255),sky2=RGB(cyan)
' --- Create_Checkerboard Source
For f =0 To 288 Step 32
Line f,hh-1,f+15,hh-1,,c1:Line f+16,hh-1,f+31,hh-1,,c2
Line f,hh,f+15,hh,,c2:Line f+16,hh,f+31,hh,,c1
Next
Box 8,16,304,72,,sky,sky
Line 8,51,311,51,,sky1:Line 8,52,311,52,,sky2
main:
p=0
Do
For y = 0 To 37
mult=y<<1
f=z_dist(y):sy=y+53:w=200-f*2-y2'w=144-mult
If mmb4w Then
IMAGE RESIZE_FAST f+camX,hh-Bcl(p,y+50), w,1, 8, y+53,304,1
Else
BLIT RESIZE f,f,f+camX,hh-Bcl(p,y+50), w,1, 8, y+53,304,1
End If
Next y
' --- Keyboard ---
k$ = Inkey$
Select Case k$
Case "w", "W"
Inc P,speed:p=p Mod 15 ' vorwrts

Case "s", "S"
p=p-speed:If p<0 Then p=15

Case "a", "A"
camX = camX - speed:If camX<0 Then camX=31

Case "d", "D"
camX = camX + speed:camX = camX Mod 32
End Select
If mmb4w Then
Page copy 1,0
'Page write 0
Else
FRAMEBUFFER copy f,n,b
End If
'pause 20
Loop
Sub phase
'Precalculation pharse lookup table
Local integer X,Y, SW = 120,CYCLES = 7
Local C_VALUE = (2 * Pi * CYCLES) / (SW * SW),START_PHASE = 0,Agl
For dst=0 To 15
For X = 0 To 119
Agl = C_VALUE * X * X + START_PHASE
Y = Int(Sin(Agl)*5)
bcl(dst,120-x)=Not(y>0)
Next X
Inc START_PHASE, 0.393
Next
End Sub

Data 36, 39, 43, 46, 50, 54, 57, 61, 64, 68, 72,75, 79, 82, 86
Data 89, 93, 97, 100, 104, 107, 111, 115, 118, 122, 125, 129
Data 133, 136, 140, 143, 147, 151, 154, 158, 161, 165, 169

Runs faster smoother on Pico than on Windows

Edited 2026-03-10 00:57 by Martin H.

'no comment

vegipete

Guru

Joined: 29/01/2013
Location: Canada
Posts: 1168

Posted: 08:08pm 09 Mar 2026

Copy link to clipboard

Print this post

That's fun! Runs pretty fast on MMB4W if your keyboard repeat rate is high.

Here's a modification with acceleration and friction: (still AWSD keys to move)
Only tested on MMB4W.

Dim integer mmb4w
Dim integer Bcl(16,160),speed=3
CONST SMAX=0.025
CONST FRICTION=0.9999
CONST ACCEL=0.005
phase
' --- Initialisierung ---
CLS
' --- Init_Graphics: Setup 320x240 Resolution, Layer-Buffer).
If MM.DEVICE$ = "MMBasic for Windows" Then mmb4w = 1
If mmb4w Then
MODE 7
PAGE WRITE 1
CLS
Else
'Pico
MODE 2
FRAMEBUFFER create : FRAMEBUFFER write f
End If
' 2. Z-Table
Dim integer x,y, z_dist(38)
For y = 0 To 37
Read scal:z_dist(y)=16+(scal/4)
Next y

CLS 'clear FRAMEBUFFER
Dim float xpos=0,ypos=0,dx=0,dy=0
Dim integer hh=120,hw=160,f,n,w
Dim integer c1=RGB(0,180,0),c2=RGB(White)
Dim Integer sky=RGB(0,85,255),sky1=RGB(0,170,255),sky2=RGB(cyan)
' --- Create_Checkerboard Source
For f =0 To 288 Step 32
Line f,hh-1,f+15,hh-1,,c1:Line f+16,hh-1,f+31,hh-1,,c2
Line f,hh,f+15,hh,,c2:Line f+16,hh,f+31,hh,,c1
Next
Box 8,16,304,72,,sky,sky
Line 8,51,311,51,,sky1:Line 8,52,311,52,,sky2
main:
p=0
Do
if abs(dx) < .0001 then
dx = 0
else
dx = dx * FRICTION
inc xpos,dx
end if
camX = xpos mod 32 : if camX < 0 then inc camX,32

if abs(dy) < .0001 then
dy = 0
else
dy = dy * FRICTION
inc ypos,dy
end if
p = ypos mod 15 : if p < 0 then inc p,15

For y = 0 To 37
'y2 = y<<1
'mult=y<<1
f=z_dist(y):sy=y+53:w=200-f*2 '-y2 'w=144-mult
If mmb4w Then
IMAGE RESIZE_FAST f+camX,hh-Bcl(p,y+50), w,1, 8, y+53,304,1
Else
BLIT RESIZE f,f,f+camX,hh-Bcl(p,y+50), w,1, 8, y+53,304,1
End If
Next y
' --- Keyboard ---
k$ = Inkey$
Select Case k$
Case "w", "W"
'Inc P,speed:p=p Mod 15 ' vorwrts
inc dy,ACCEL
dy = min(dy, SMAX)

Case "s", "S"
'p=p-speed:If p<0 Then p=15
inc dy,-ACCEL
dy = max(dy,-SMAX)

Case "a", "A"
'camX = camX - speed:If camX<0 Then camX=31
inc dx,-ACCEL
dx = max(dx,-SMAX)

Case "d", "D"
'camX = camX + speed:camX = camX Mod 32
inc dx,ACCEL
dx = min(dx, SMAX)

End Select
If mmb4w Then
Page copy 1,0
'Page write 0
Else
FRAMEBUFFER copy f,n,b
End If
'pause 20
Loop
Sub phase
'Precalculation pharse lookup table
Local integer X,Y, SW = 120,CYCLES = 7
Local C_VALUE = (2 * Pi * CYCLES) / (SW * SW),START_PHASE = 0,Agl
For dst=0 To 15
For X = 0 To 119
Agl = C_VALUE * X * X + START_PHASE
Y = Int(Sin(Agl)*5)
bcl(dst,120-x)=Not(y>0)
Next X
Inc START_PHASE, 0.393
Next
End Sub

Data 36, 39, 43, 46, 50, 54, 57, 61, 64, 68, 72,75, 79, 82, 86
Data 89, 93, 97, 100, 104, 107, 111, 115, 118, 122, 125, 129
Data 133, 136, 140, 143, 147, 151, 154, 158, 161, 165, 169

Visit Vegipete's *Mite Library for cool programs.

Martin H.

Guru

Joined: 04/06/2022
Location: Germany
Posts: 1447

Posted: 04:23am 10 Mar 2026

Copy link to clipboard

Print this post

vegipete said
Here's a modification with acceleration and friction: (still AWSD keys to move)
Only tested on MMB4W.

Hey Pete, it gives you a completely different riding experience, reminiscent of skating. Great addition.

Cheers
Martin
Edit:Sadly, it runs extremely slowly(is not due to the image generation) on the first attempt on the Pico.... I'll have a look what the problem might be.
Edited 2026-03-10 18:26 by Martin H.

'no comment

vegipete

Guru

Joined: 29/01/2013
Location: Canada
Posts: 1168

Posted: 04:51pm 10 Mar 2026

Copy link to clipboard

Print this post

I tuned the SMAX (max speed,) FRICTION and ACCEL values for MMB4W, which obviously calculates much faster. They will need tuning for the PicoMite.

Visit Vegipete's *Mite Library for cool programs.

Martin H.

Guru

Joined: 04/06/2022
Location: Germany
Posts: 1447

Posted: 05:12pm 10 Mar 2026

Copy link to clipboard

Print this post

vegipete said I tuned the SMAX (max speed,) FRICTION and ACCEL values for MMB4W, which obviously calculates much faster. They will need tuning for the PicoMite.

Const SMAX=1.8
Const FRICTION=1
Const ACCEL=0.5
They run quite well, not quite as nicely as under Windows, but still quite pleasantly.
Thanks for the support.
Martin

'no comment

Martin H.

Guru

Joined: 04/06/2022
Location: Germany
Posts: 1447

Posted: 10:46am 22 Mar 2026

Copy link to clipboard

Print this post

Since it's Sunday,
I dug up some old code and sped things up using the new BLIT RESIZE command

On the PICO2 HDMI @252MHz, this gives me 47 FPS, so there's now room to include enemie cars, trees, and signs

Road.zip
Have Fun
Martin

Link to the original post
Edited 2026-03-22 20:51 by Martin H.

'no comment

Peter63
Senior Member

Joined: 28/07/2017
Location: Sweden
Posts: 153

Posted: 02:37pm 03 Apr 2026

Copy link to clipboard

Print this post

Quote Road.zip
Have Fun
Martin

have tried it on, PicoMiteVGA MMBasic USB RP2040 Edition V6.02.01

have a nice weekend

Peter63

Print this page

To reply to this topic, you need to log in.