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WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2991

Posted: 07:19am 25 Oct 2015

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Try removing the space between AND and &h/b.

I was trying all kind of things and there were definite improvements removing spaces!

WW

twofingers

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Joined: 02/06/2014
Location: Germany
Posts: 1773

Posted: 11:15am 25 Oct 2015

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WhiteWizzard said Try removing the space between AND and &h/b.

For C=0 To Q:B(C)=(C And&H4)*W+(C And&H2)*U+(C And 1)*255:Next

Result: no difference!

Code so far (365127ms, uM2@48Mhz 240x320px LCD)

'JULIA.BAS - Draws Julia set fractal images
'by loki
CPU 48 ' for uM2
Dim As Integer H, V, C, W, U, Q=80 'max iterations
Dim As integer B(Q+1)

CLS

'Specify initial values
S = 1.30
T = 0.95
'------------------------------------------------*
'Set the Julia set constant [eg C = -1.2 + 0.8i]
D = -0.78
E = -0.20
'------------------------------------------------*

GAP = MM.VRes / MM.HRes
SIZE = 2.50
P = SIZE / MM.HRes
O = (SIZE * GAP) / MM.VRes
H=MM.HRes-1
V=MM.VRes-1
W=4177920
U=32640

Timer=0
For C=0 To Q:B(C)=(C And &H4)*W+(C And &H2)*U+(C And 1)*255:Next
For X=0 To H:M=X*P-S:For Y=0 To V:J=Y*O-T:R=M
For C=0 To Q:If R*R+J*J>=&H4 Then Exit For
N=R*R-J*J+D:J=&H2*R*J+E:R=N
Next
Pixel X,Y,B(C):Next:Next

Print Timer
End

Regards
Michael

‚My name is Ozymandias, king of kings
Look on my works, ye Mighty, and despair!‘
Nothing beside remains. Round the decay
Of that colossal wreck, boundless and bare
The lone and ...

TassyJim

Guru

Joined: 07/08/2011
Location: Australia
Posts: 6607

Posted: 12:44pm 25 Oct 2015

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Using Michael's latest code on my MM+ @100MHz with 7inch display
1317 seconds.
That's down form the original 1979 seconds or 22 minutes compared with 33 minutes.
Time for another beer at least!

Jim

VK7JH
MMedit

vegipete

Guru

Joined: 29/01/2013
Location: Canada
Posts: 1185

Posted: 07:23am 26 Oct 2015

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What, oh what, have we created?

Which of these would you rather debug? ;-)

For C=0 To Q:B(C)=(C And &H4)*W+(C And &H2)*U+(C And 1)*255:Next
For X=0 To H:M=X*P-S:For Y=0 To V:J=Y*O-T:R=M
For C=0 To Q:If R*R+J*J>=&H4 Then Exit For
N=R*R-J*J+D:J=&H2*R*J+E:R=N
Next
Pixel X,Y,B(C):Next:Next

For X = 0 To (MM.HRes - 1)
CX = X * Xdelta + RealOffset
For Y = 0 To (MM.VRes - 1)
CY = Y * YDelta + ImaginOffset
Zr = CX
Zi = CY
COUNT = 0
'Begin Iteration loop
Do While (( COUNT <= MAXIT ) And (( Zr * Zr + Zi * Zi ) < 4 ))
new_Zr = Zr * Zr - Zi * Zi + CRealVal
new_Zi = 2 * Zr * Zi + CImagVal
Zr = new_Zr
Zi = new_Zi
COUNT = COUNT + 1
Loop
PIXEL X, Y, (COUNT and 4) * 4177920 + (COUNT and 2) * 32640 + (COUNT and 1) * 255)
Next Y
Next X

Visit Vegipete's *Mite Library for cool programs.

twofingers

Guru

Joined: 02/06/2014
Location: Germany
Posts: 1773

Posted: 07:42am 26 Oct 2015

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vegipete said What, oh what, have we created?

A monster!

(The sleep of reason produces monsters)

And this proves also that not only C programmers can produce cryptic code!

... I hope newbies (in Basic programming) will not take this as a good example!

Michael

‚My name is Ozymandias, king of kings
Look on my works, ye Mighty, and despair!‘
Nothing beside remains. Round the decay
Of that colossal wreck, boundless and bare
The lone and ...

MicroBlocks

Guru

Joined: 12/05/2012
Location: Thailand
Posts: 2209

Posted: 07:59am 26 Oct 2015

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When speed is the goal then everything is allowed.

How much time is spend in the PIXEL routine?
Maybe just make a dummy subroutine to measure it.
[code]
SUB DUMMYPIXEL(x,y,c)
END SUB
[/code]

Microblocks. Build with logic.

twofingers

Guru

Joined: 02/06/2014
Location: Germany
Posts: 1773

Posted: 09:22am 26 Oct 2015

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MicroBlocks said When speed is the goal then everything is allowed.

How much time is spend in the PIXEL routine?
Maybe just make a dummy subroutine to measure it.
[code]
SUB DUMMYPIXEL(x,y,c)
END SUB
[/code]

Hi MB,

I replaced the Pixel routine with a sub called "Dixel X,Y,B(C)". Result 390161 (instead of 365127). This is confusing and means a empty routine takes longer than the original routine.

When I delete the Pixel routine:

Timer=0
For C=0 To Q:B(C)=(C And &H4)*W+(C And &H2)*U+(C And 1)*255:Next
For X=0 To H:M=X*P-S:For Y=0 To V:J=Y*O-T:R=M
For C=0 To Q:If R*R+J*J>=&H4 Then Exit For
N=R*R-J*J+D:J=&H2*R*J+E:R=N
Next
Next:Next

Print Timer

I get 350784 (instead of 365127) =-14343ms. A 240x320 LCD has 76800 pixel.
14343/76800=0,187ms per pixel (using "Pixel X,Y,B(C)").

Regards
Michael

EDIT:
This allows you to confirm the above result:
3852 ticks=0.160375ms

CPU 48
Dim integer x=1,y=2,b=8
Dim integer empty=2957
Dim float tick_time=1/(48000000/2) 'for CPU 48, 1 Tick = 2 CPU cycles

x=StartCT()
Pixel X,Y,B(C)
x=ReadCT()
Print "Execution time:" x-empty " ticks ="; Int(tick_time*(x-empty)*1000000);"us (Pixel X,Y,B(C) )"

End

C source (very simple, quick & dirty and NOT generally applicable)

long long StartCT(void)
{
unsigned int zero=0;
asm volatile("mtc0 %0, $9": "+r"(zero));
return 0;
}

long long ReadCT(void)
{
unsigned int current_ticks;
asm volatile("mfc0 %0, $9": "=r"(current_ticks));
return current_ticks;
}

EDIT2:
Obviously X,Y should be integers and this takes again 3 sec less (362091ms):

'JULIA.BAS - Draws Julia set fractal images
'by loki
CPU 48 ' for uM2
Dim As Integer H, V, C, W, U, Q=80 'max iterations
Dim As integer B(Q+1),X,Y

CLS

'Specify initial values
S = 1.30
T = 0.95
'------------------------------------------------*
'Set the Julia set constant [eg C = -1.2 + 0.8i]
D = -0.78
E = -0.20
'------------------------------------------------*

GAP = MM.VRes / MM.HRes
SIZE = 2.50
P = SIZE / MM.HRes
O = (SIZE * GAP) / MM.VRes
H=MM.HRes-1
V=MM.VRes-1
W=4177920
U=32640

Timer=0
For C=0 To Q:B(C)=(C And &H4)*W+(C And &H2)*U+(C And 1)*255:Next
For X=0 To H:M=X*P-S:For Y=0 To V:J=Y*O-T:R=M
For C=0 To Q:If R*R+J*J>=&H4 Then Exit For
N=R*R-J*J+D:J=&H2*R*J+E:R=N
Next
Pixel X,Y,B(C):Next:Next
Print Timer
End

Edited by twofingers 2015-11-09

‚My name is Ozymandias, king of kings
Look on my works, ye Mighty, and despair!‘
Nothing beside remains. Round the decay
Of that colossal wreck, boundless and bare
The lone and ...

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