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WhiteWizzard
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Joined: 05/04/2013
Location: United Kingdom
Posts: 2944

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: 1593

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

causality ≠ correlation ≠ coincidence

TassyJim

Guru

Joined: 07/08/2011
Location: Australia
Posts: 6283

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

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Joined: 29/01/2013
Location: Canada
Posts: 1134

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: 1593

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

causality ≠ correlation ≠ coincidence

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: 1593

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

causality ≠ correlation ≠ coincidence

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