Calculated Image

A billion years ago I found a one liner in a magazine and it made a pretty cool image. Recently I found it again and thought it would be cool to try it on a modern computer. Below is the algorithm I came up with. Just drop a Picture Box onto a form, add an X, Y and Decimal (from .2 to .9):

// Created by Gregg Buntin
private void DrawImage()
{
    int sizeX = Convert.ToInt32(tbX.Text); // this is the X (width) of the image
    int sizeY = Convert.ToInt32(tbY.Text); // this is the Y (height) of the image
    int halfX = sizeX / 2;
    int halfY = sizeY / 2;
    calculatedImage = new Bitmap(sizeX, sizeY);
    Color tempColor = new Color();
    double num = Convert.ToDouble(tbDec.Text); // This is where you plug in the Decimal value
    for (int Y = -(halfY); Y < 1; Y++)
    {
        int Y2 = Y * Y;
        for (int X = -(halfX); X < 1; X++)
        {
            tempColor = Color.White;
            double tempR = Math.Pow((Y2 + (X * X)), num);
            double R = (10000000 - tempR) / 2;
            int intR = Convert.ToInt32(R);
            double roundR = Math.Truncate(R);
            if (roundR != intR) tempColor = Color.Black;
            int X1 = X + halfX;
            int Y1 = Y + halfY;
            calculatedImage.SetPixel(X1, Y1, tempColor);
            calculatedImage.SetPixel(sizeX - 2 - X1, Y1, tempColor);
            calculatedImage.SetPixel(X1, sizeY - 2 - Y1, tempColor);
            calculatedImage.SetPixel(sizeX - 2 - X1, sizeY - 2 - Y1, tempColor);
        } // for X
    } // for Y
    pbImage.Image = calculatedImage;
} // method DrawImage

Cool AppleSoft Emulator

I've posted about this one before (7 years ago!) but I've been feeling nostalgic lately so I revisited it... The site is at http://www.calormen.com/Applesoft/ and is an AppleSoft Basic interpreter written in JavaScript. Joshua Bell did a great job with it. I've sent him several programs (4 recently) and he included them in his Samples list. He is a really great guy. You should try the emulator out... be sure to check my programs :)

One more Applesoft Program

I wrote this as two programs so long ago, I don't remember how they work :)

I thought for sure that I lost these, but stumbled across them today so I wanted to post them here for posterity.  I espcially like version 2.

If I get really ambitious I might try to write version 2 into assembly... not sure I remember assembly quite that well yet (I can read it well enough, but can I still write it???)

 1   TEXT : HOME

 2   ?  "Lo Res Graphics Fun by Gregg"

 5   ? "Which Version 1 or 2 (3 to quit): ";: GET K$

 6   IF K$ = "2" THEN 10

 7   IF K$ = "1" THEN 510

 8   IF K$ = "3" THEN HOME : ? "Bye!" : END

 9   GOTO 1

 10  TEXT : HOME : GR :T = 0:X = 1:Y = 38:C1 = 1:Z = 0:C2 = 2:XX = 0:YY = 0

 12 X1 = 19:Y1 = 20:C3 = 4

 13 X2 = 19:Y2 = 20:C4 = 6

 15  VTAB 22: PRINT "HIT ESC TO EXIT"

 20  COLOR= C1: HLIN X,Y AT X: HLIN X,Y AT Y: VLIN X,Y AT X: VLIN X,Y AT Y

 30 X = X + 1:Y = Y - 1:T = T + 1: IF T = 9 THEN XX = 1:YY = 38:Z = 1

 40  IF X = 20 THEN X = 1:Y = 38:C1 = C1 + 2: IF C1 > 15 THEN C1 = 1

 50  IF Z <  > 1 THEN 80

 60  COLOR= C2: HLIN XX,YY AT XX: HLIN XX,YY AT YY: VLIN XX,YY AT YY: VLIN XX,YY AT XX

 70 XX = XX + 1:YY = YY - 1: IF XX = 20 THEN XX = 1:YY = 38:C2 = C2 + 2: IF C2 > 14 THEN C2 = 2

 80  COLOR= C3: HLIN X1,Y1 AT X1: HLIN X1,Y1 AT Y1: VLIN X1,Y1 AT X1: VLIN X1,Y1 AT Y1

 90 X1 = X1 - 1:Y1 = Y1 + 1:

 100  IF X1 = 0 THEN X1 = 19:Y1 = 20:C3 = C3 + 2: IF C3 > 15 THEN C3 = 1

 105  IF Z <  > 1 THEN 20

 110  COLOR= C4: HLIN Y2,X2 AT X2: HLIN Y2,X2 AT Y2: VLIN Y2,X2 AT X2: VLIN Y2,X2 AT Y2

 120 X2 = X2 - 1:Y2 = Y2 + 1

 130  IF X2 = 0 THEN X2 = 19:Y2 = 20:C4 = C4 + 2: IF C4 > 15 THEN C4 = 1

 200 K =  PEEK ( - 16384): IF K <  > 155 THEN 20

 210  POKE  - 16368,0: TEXT : HOME : GOTO 1

 510  TEXT : HOME : GR :T = 0:X = 1:Y = 38:C1 = 1:Z = 0:C2 = 2:XX = 0:YY = 0

 520  COLOR= C1: HLIN X,Y AT X: HLIN X,Y AT Y: VLIN X,Y AT X: VLIN X,Y AT Y

 530 X = X + 1:Y = Y - 1:T = T + 1: IF T = 9 THEN XX = 1:YY = 38:Z = 1

 540  IF X = 39 THEN X = 1:Y = 38:C1 = C1 + 2: IF C1 > 15 THEN C1 = 1

 550  IF Z <  > 1 THEN 520

 560  COLOR= C2: HLIN XX,YY AT XX: HLIN XX,YY AT YY: VLIN XX,YY AT YY: VLIN XX,YY AT XX

 570 XX = XX + 1:YY = YY - 1: IF XX = 39 THEN XX = 1:YY = 38:C2 = C2 + 2: IF C2 > 14 THEN C2 = 2

 580  VTAB 22: PRINT "HIT 'ESC' TO EXIT":K =  PEEK ( - 16384): IF K <  > 155 THEN 520

 590  POKE  - 16368,0: TEXT : HOME : GOTO 1

Assembly is Fun!

It has been a LONG time since I seriously wrote any 6502 Assembly code, but I used to do it all the time.  I would write it out on paper first then type it in once I had it where I thought I wanted it.  Paper made it alot easier to see everything all at once (due to the tiny screens in the old days).  I think I still have a page or two of hand written code.  If I find it I'll scan and post it just for fun.

So, I was playing with this site: http://www.6502asm.com/

And decided to take an old Apple ][ Assembly program I wrote EONS ago and adapt it to work on that site.  Got it to work pretty well and even submitted it for their examples page.  I do have a Game Of Life I wrote once that I want to try and adapt, but not today :)

If you write anything cool, let me know.

Yawn

Tired, so tired. Not sleeping much (and haven't been for about a year). Most of it is because of work... oh well. Maybe someday it will get better (or I'll win the lottery... yah right).

So awhile ago I found this site: http://www.calormen.com/Applesoft/

Its fun to sometimes play with.

Go ahead and put this code in there:

10 TEXT : HOME : INPUT "NUMBER OF POINTS:";A: HCOLOR= 3
20 HGR : POKE -16302,0
30 FOR T1 = 0 TO (2 * 3.14) - .001 STEP ((2 * 3.14) / A)
40 FOR T2 = T1 + (2 * 3.14) / A TO (2 * 3.14) - .001 STEP (2 * 3.14) / A
50 HPLOT ( COS (T1) * 95 + 127),( SIN (T1) * 95 + 95) TO ( COS (T2) * 95 + 127),( SIN (T2) * 95 + 95)
60 NEXT
70 NEXT
80 GET A$
90 GOTO 10

or This one

10 TEXT
20 HOME
30 INPUT "Enter a number from 1 to 8:";N
40 IF N > 0 AND N < 8 THEN F = 128
50 E = 0
60 K = 4 ^ N
70 FOR X = 1 TO N
80 U = F
90 F = - E / 2
100 E = U / 2
110 NEXT
120 HGR
130 HCOLOR= 3
140 X = 80
150 Y = 70
160 HPLOT X,Y
170 FOR M = 1 TO K
180 Z = M
190 X = X + F
200 Y = Y + E
210 HPLOT TO X,Y
220 FOR A = 0 TO 1
230 Z = Z / 2
240 Q = INT (Z)
250 A = Z - Q
260 NEXT
270 A = (Q / 2 = INT (Q / 2)) * 2 - 1
280 U = F
290 F = A * E
300 E = - A * U
310 NEXT
320 GOTO 10

I sent several of my programs to the guy that wrote it so hopefully he includes them in his 'sample' list. Especially the last one I sent him... its pretty cool.

Here is some old code for you...

The Apple ][ computer didn't have super fancy graphics.  They had a portion of memory mapped to the graphic screen.  Since I don't really feel like trying to explain it here because others have done it far better than I could read this: http://en.wikipedia.org/wiki/Apple_II_graphics   Specifically the Hires Graphics section.

Now, I had a need to be able to scroll the Hires Screen left or right.  Thanks to a series of articles by David Lubar in Creative Computing called The Graph Paper (October 1982 -> March 1983) and an article called Lookup Tables (March 1982) I had a very good understanding of how each byte in memory made up the picture that was displayed so I wrote the following code using the SC Macro Assembler.  This version of the code did the scroll left.

The 'Lookup Table' allowed me to access each line of the hires screen directly and in order (since the screen was 'interlaced').

BTW, comments are for losers. :)

1000        .OR $6000

1010        .TF SCROLLLEFT

1020        .LIST OFF

1030        JMP HERE

1040 TABLHI .HS 2024282C3034383C

1050        .HS 2024282C3034383C

1060        .HS 2125292D3135393D 

1070        .HS 2125292D3135393D

1080        .HS 22262A2E32363A3E

1090        .HS 22262A2E32363A3E

1100        .HS 23272B2F33373B3F

1110        .HS 23272B2F33373B3F

1120        .HS 2024282C3034383C 

1130        .HS 2024282C3034383C

1140        .HS 2125292D3135393D 

1150        .HS 2125292D3135393D

1160        .HS 22262A2E32363A3E

1170        .HS 22262A2E32363A3E 

1180        .HS 23272B2F33373B3F

1190        .HS 23272B2F33373B3F

1200        .HS 2024282C3034383C 

1210        .HS 2024282C3034383C

1220        .HS 2125292D3135393D

1230        .HS 2125292D3135393D

1240        .HS 22262A2E32363A3E 

1250        .HS 22262A2E32363A3E

1260        .HS 23272B2F33373B3F

1270        .HS 23272B2F33373B3F

1280 TABLLO .HS 0000000000000000

1290        .HS 8080808080808080

1300        .HS 0000000000000000

1310        .HS 8080808080808080

1320        .HS 0000000000000000 

1330        .HS 8080808080808080 

1340        .HS 0000000000000000

1350        .HS 8080808080808080

1360        .HS 2828282828282828

1370        .HS A8A8A8A8A8A8A8A8

1380        .HS 2828282828282828

1390        .HS A8A8A8A8A8A8A8A8 

1400        .HS 2828282828282828 

1410        .HS A8A8A8A8A8A8A8A8 

1420        .HS 2828282828282828 

1430        .HS A8A8A8A8A8A8A8A8 

1440        .HS 5050505050505050

1450        .HS D0D0D0D0D0D0D0D0

1460        .HS 5050505050505050 

1470        .HS D0D0D0D0D0D0D0D0 

1480        .HS 5050505050505050 

1490        .HS D0D0D0D0D0D0D0D0

1500        .HS 5050505050505050 

1510        .HS D0D0D0D0D0D0D0D0 

1520 HERE   STA $C050 

1530        STA $C057

1540        STA $C054

1550        STA $C052

1560        LDX #$00

1570 A7     LDA TABLLO,X  

1580        STA $F0

1590        LDA TABLHI,X

1600        STA $F1

1610        CLC

1620        LDY #$27

1630 A6     LDA ($F0),Y

1640        ROL

1650        BCC A1

1660        ROR

1670        BCC A2

1680        SEC

1690        ROR

1710        JMP A3

1720 A2     ROL

1730        CLC

1740        ROR

1750        SEC

1760        ROR

1770        JMPA3

1780 A1     ROR

1790        BCC A4

1800        ROL

1810        SEC

1820        ROR

1830 A4     ROR

1840 A3     STA ($F0),Y

1850        ROR

1860        DEY

1870        BMI A5

1880        ROL

1890        JMP A6

1900 A5     INX

1910        CPX #$C0

1920        BNE A7

1930        RTS

And the code to scroll right looks like this:

1000        .OR $6000

1010        .TF SCROLLRGHT

1020        .LIST OFF

1030        JMP HERE

1040 TABLHI .HS 2024282C3034383C

1050        .HS 2024282C3034383C

1060        .HS 2125292D3135393D 

1070        .HS 2125292D3135393D

1080        .HS 22262A2E32363A3E

1090        .HS 22262A2E32363A3E

1100        .HS 23272B2F33373B3F

1110        .HS 23272B2F33373B3F

1120        .HS 2024282C3034383C 

1130        .HS 2024282C3034383C

1140        .HS 2125292D3135393D 

1150        .HS 2125292D3135393D

1160        .HS 22262A2E32363A3E

1170        .HS 22262A2E32363A3E 

1180        .HS 23272B2F33373B3F

1190        .HS 23272B2F33373B3F

1200        .HS 2024282C3034383C 

1210        .HS 2024282C3034383C

1220        .HS 2125292D3135393D

1230        .HS 2125292D3135393D

1240        .HS 22262A2E32363A3E 

1250        .HS 22262A2E32363A3E

1260        .HS 23272B2F33373B3F

1270        .HS 23272B2F33373B3F

1280 TABLLO .HS 0000000000000000

1290        .HS 8080808080808080

1300        .HS 0000000000000000

1310        .HS 8080808080808080

1320        .HS 0000000000000000 

1330        .HS 8080808080808080 

1340        .HS 0000000000000000

1350        .HS 8080808080808080

1360        .HS 2828282828282828

1370        .HS A8A8A8A8A8A8A8A8

1380        .HS 2828282828282828

1390        .HS A8A8A8A8A8A8A8A8 

1400        .HS 2828282828282828 

1410        .HS A8A8A8A8A8A8A8A8 

1420        .HS 2828282828282828 

1430        .HS A8A8A8A8A8A8A8A8 

1440        .HS 5050505050505050

1450        .HS D0D0D0D0D0D0D0D0

1460        .HS 5050505050505050 

1470        .HS D0D0D0D0D0D0D0D0 

1480        .HS 5050505050505050 

1490        .HS D0D0D0D0D0D0D0D0

1500        .HS 5050505050505050 

1510        .HS D0D0D0D0D0D0D0D0 

1520 HERE   STA $C050 

1530        STA $C057

1540        STA $C054

1550        STA $C052

1560        LDX #$00

1570 A7     LDA TABLLO,X  

1580        STA $F0

1590        LDA TABLHI,X

1600        STA $F1

1610        CLC

1620        LDY #$00

1630 A6     LDA ($F0),Y

1640        ROL

1650        BCC A1

1660        ROL

1670        BCC A2

1680        SEC

1690        ROR

1700        SEC

1710        BCS A3

1720 A2     SEC

1730        ROR

1740        CLC

1750        BCC A3

1760 A1     ROL

1770        BCC A4

1780        CLC

1790        ROR

1800        SEC

1810        BCS A3

1820 A4     CLC

1830        ROR

1840        CLC

1850 A3     STA ($F0),Y

1860        ROR

1870        INY

1880        CPY #$28

1890        BEQ A5

1900        ROL

1910        JMP A6

1920 A5     INX

1930        CPX #$C0

1940        BNE A7

1950        RTS

The code is very close but there are some important differences (like line 1620, 00 starts on the left of the line and #27 starts on the right of the line).

Now, you may ask, Why did I bother posting this?  Because I could and I felt like sharing.  I do have some old notebook pages I found with some hand written code on them that I'm going to scan in and post here at some point in the near future.

Ah, the old days...

So, long ago I was deep into Apple ][ computers. I could hand code assembly directly into the monitor (until I got my hands on SC Macro Assembler).. A time when Boot Code tracing was the best way to get into the guts of a game and when windows were things you looked out of.

My buddy and I would figure out some cool piece of code and then share it. Each of us trying to be better than the other.

Once I figure out an easy way to link to some of the stuff we wrote, I'll post links to .bin files that will run in any Apple ][ emulator. Sure, its not up to today's standards but for the time it was pretty cool (20+ years ago!).

I miss the simplicity of the code & operating systems. Today's OSes just have way too much bloat.
Ah well... everything must pass to dust eventually