
-----------------------------------
mike200015
Sat Feb 05, 2005 12:40 pm

Moving in an Arc?!
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Is there a way to make sumthing move in an arc shape, i made a sun move across the sky , but it jus goes in a triangle shape, but i want it to go more like an arc. Heres the code: 

var x2, y2 : int
x2 := 0
y2 := 40
colourback(brightblue)
%Sun Rising
for i : 1 .. 36
    setscreen ("offscreenonly")
    View.Update
cls
    %sun
    drawfilloval (x2, y2, 20, 20, yellow)
    x2 += 8
    y2 += 10
    delay (300)
end for

for i : 1 .. 36
    setscreen ("offscreenonly")
    View.Update
cls
    %sun
    drawfilloval (x2, y2, 20, 20, yellow)
    x2 += 8
    y2 -= 10
    delay (300)
end for

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Bacchus
Sat Feb 05, 2005 3:15 pm


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parabolas, do a search for topics made by Homer_Simpson, hes probably the best on the subject for parabolas in turing (that i kno of)

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Neo
Sat Feb 05, 2005 3:38 pm


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parabolas, do a search for topics made by Homer_Simpson, hes probably the best on the subject for parabolas in turing (that i kno of)

Actually all you have to know is a bit of grade 10 math. :lol: 


var x, y := 0.0

setscreen ("offscreenonly")
colourback (black)
loop
    cls
    y := -.002 * (x - 320) ** 2 + 180
    x += 1
    drawfilloval (round (x), round (y), 20, 20, yellow)
    if y < 0 then
        x := 50.0
    end if
    View.Update
    delay (5)
end loop


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Bacchus
Sat Feb 05, 2005 3:56 pm


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ya unless you cant remember ne math cause u havent had it for about a year lol

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Andy
Sat Feb 05, 2005 4:00 pm


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law of the locus

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mike200015
Sat Feb 05, 2005 5:49 pm


-----------------------------------
parabolas, do a search for topics made by Homer_Simpson, hes probably the best on the subject for parabolas in turing (that i kno of)

Actually all you have to know is a bit of grade 10 math. :lol: 


var x, y := 0.0

setscreen ("offscreenonly")
colourback (black)
loop
    cls
    y := -.002 * (x - 320) ** 2 + 180
    x += 1
    drawfilloval (round (x), round (y), 20, 20, yellow)
    if y < 0 then
        x := 50.0
    end if
    View.Update
    delay (5)
end loop


hey thank you very much neo, it works really well!

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TheZsterBunny
Sun Feb 06, 2005 4:38 pm


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lol. i had white for grade 10 math. can't remember a word of it. ^_^;

someone care to do a quick review on parabolas?


-Z

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mike200015
Tue Feb 08, 2005 5:16 pm


-----------------------------------
parabolas, do a search for topics made by Homer_Simpson, hes probably the best on the subject for parabolas in turing (that i kno of)

Actually all you have to know is a bit of grade 10 math. :lol: 


var x, y := 0.0

setscreen ("offscreenonly")
colourback (black)
loop
    cls
    y := -.002 * (x - 320) ** 2 + 180
    x += 1
    drawfilloval (round (x), round (y), 20, 20, yellow)
    if y < 0 then
        x := 50.0
    end if
    View.Update
    delay (5)
end loop


what does that mean.   the y:= -.002...    how does it curve, i never learnt that? :?  can anyone explain that

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Cervantes
Tue Feb 08, 2005 5:50 pm


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f(x) = a(x - p)^2 + q

a represents the "vertical stretch" or "vertical compression".  A value > 1 will vertically stretch the parabola.  A value between 0 and 1 will make the parabola compressed vertically.  This can also be looked at as being stretched vertically.  (Note that a cannot = 0)  If a > 0, the parabola will "open upwards", meaning that it looks like a U.  If a < 0, the parabola will "open downwards", meaning that it looks like an n.  

In Neo's code, -.002 is the value for a.  Changing it should yield a parabola that is vertically stretched or compressed.

I'm assuming that this code,

    if y < 0 then
        x := 50.0
    end if

is trying to reset the parabola so the ball will move across the screen again.  Mind you, it tends to screw things up if you change a to some other value.

-Cervantes

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mike200015
Thu Feb 10, 2005 1:09 pm


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got it.. thnx cervantes.. 1 more thing tho, what does the rest mean.. 
(x - 320) ** 2 + 180

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zylum
Thu Feb 10, 2005 4:28 pm


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p is the y of the vertex and q is the x.

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Drakain Zeil
Sat Feb 12, 2005 8:55 am


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Paroblas are in the form f(x)=x^2

Just change your position on the X axis, by subbing in that number to the function, and you have your y-position, you can move in an arc.

There's elipses, circles and hyperbola are also, but those aren't functions and therefore you have somthing harder to stay in line with any consistancy.. errors could occur, etc.

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ssr
Sat Feb 12, 2005 10:32 pm


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LOL 
Im just learning parabolas right now.
it was pretty ok.
Right now, I wanted to make some game like a  guy jump and comes down, tnx for this topic guys :D  :D  :lol:

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Drakain Zeil
Sun Feb 13, 2005 11:31 am


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Ah, paroblas, once you get into 11/12 math, you'll laugh at "how hard" some of the math you did back then... y=mx+b is what we do in one step now, at the time it seems so complex.

Something to be said about the teaching done there eh?

Oh, all of those "soccer slimes" that lots of people play, use paroblas too.. if you don't know what I'm taking about, don't worry about it.

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ssr
Sun Feb 13, 2005 1:12 pm


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This is kinda spam, but ya, I do agree with u,Drakain Zeil :D
