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Rolling coins
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This brougth back so many memories.....
As I was a kid, aged 6 or 7, there was this brand of chocolate powder, wich came with a scantilion, a ruler by wich we could draw on paper Exactly these shapes...
As I did back then, today a spendt hours playing with the values and seeing the shapes being drwan in my screen....
I was 7 again.... Thank you very much...
As I was a kid, aged 6 or 7, there was this brand of chocolate powder, wich came with a scantilion, a ruler by wich we could draw on paper Exactly these shapes...
As I did back then, today a spendt hours playing with the values and seeing the shapes being drwan in my screen....
I was 7 again.... Thank you very much...
There is a subtle bug in your code.
You are using an endless loop and therefore the program will not stop until you close it with task manager (optimized compiled version).
A simple correction is to use a global variable as a flag that breaks the loop when the main form is closing:
You are using an endless loop and therefore the program will not stop until you close it with task manager (optimized compiled version).
A simple correction is to use a global variable as a flag that breaks the loop when the main form is closing:
B4X:
Sub Globals
'Declare the global variables here.
Dim a, b, h, t, t1
Dim x, y, xstart, ystart
Dim showsmall, showlarge, showpole
Dim waittime, inner
Dim stop ' <---
End Sub
Sub App_Start
' Equations curtesy of mathworld.wolfram.com
stop = False
Form1.Color = cBlack
xstart = 120 : ystart = 120
xsmall = xstart : ysmall = ystart
a=40:b=10:h=10:t=0:x=0:y=0
showsmall=1 : showlarge=1 : showpole=1
waittime = 20 : inner = 1
SetTransparentColor(cWhite)
form1.ForeLayer = True
Form1.Show
t1=0
Do Until stop
If showlarge = 1 Then
form1.Circle(xstart,ystart,a,cGray)
Else
form1.Circle(xstart,ystart,a,cBlack)
End If
form1.FLine(0,0,400,400,cWhite,BF)
t=t1*cPI/180
If inner = 1 Then
z = a-b
x=z*Cos(t)+h*Cos(z/b*t)
Else
z = a+b
x=z*Cos(t)-h*Cos(z/b*t)
End If
y=z*Sin(t)-h*Sin(z/b*t)
xsmall=z*Cos(t)
ysmall=z*Sin(t)
form1.Line(xstart+x,ystart+y,xstart+x+1,ystart+y+1,cWhite,BF)
If showsmall = 1 Then
form1.FCircle(xstart+xsmall,ystart+ysmall,b,cGray)
End If
If showpole = 1 Then
form1.FLine(xstart+xsmall,ystart+ysmall,xstart+x,ystart+y,cRed)
End If
DoEvents
Sleep(waittime)
t1 = t1 + 1
Loop
End Sub
Sub Form1_Close
stop = True
End Sub
Ok - thanks Erel.
Is there a better way to plot a point than approximate it with a 2x2 block.
A 3x3 block with its centre at the correct point is more accurate than what I've done but is too thick, A 1x1 line didn't show up on my screen at all.
BTW I,40,20,40 shows that if your hula-hoop has a nail in it and is twice as big as your waist, then the nail is going to get you, always in the same place every second time round.
Better get a bigger hula hoop, and better still, make sure it is not a intergral size bigger than your waist.
I,46,20,46 makes some really interesting patterns and ensures that the nail strikes occurr evenly around your waist.
Is there a better way to plot a point than approximate it with a 2x2 block.
A 3x3 block with its centre at the correct point is more accurate than what I've done but is too thick, A 1x1 line didn't show up on my screen at all.
BTW I,40,20,40 shows that if your hula-hoop has a nail in it and is twice as big as your waist, then the nail is going to get you, always in the same place every second time round.
Better get a bigger hula hoop, and better still, make sure it is not a intergral size bigger than your waist.
I,46,20,46 makes some really interesting patterns and ensures that the nail strikes occurr evenly around your waist.
Real nice!
Will you be enhancing it?
- different sizes
- different colors (agraham's color picker maybe)
- multiple rings
- a "stop" button
- save as function (I think dzt had a nice image lib)
Yes!
I always wanted to have it as a kid... but never got it :'(
Will you be enhancing it?
- different sizes
- different colors (agraham's color picker maybe)
- multiple rings
- a "stop" button
- save as function (I think dzt had a nice image lib)
Yes!
I always wanted to have it as a kid... but never got it :'(
Last edited:
Nice application.
Reminds me also some souvenirs, having programmed something similar quite some years ago.
Specci48, my daughter, once, got a similar game (also some years ago).
I agree with Mr_Gee, you should continue in adding the features discribed by him.
Another suggestions:
- stop the drawing when it beginns to overlap (drawing the same lines)
- by default when changing the small circle, put the drawing radius at the same value.
Best regards.
Reminds me also some souvenirs, having programmed something similar quite some years ago.
Specci48, my daughter, once, got a similar game (also some years ago).
I agree with Mr_Gee, you should continue in adding the features discribed by him.
Another suggestions:
- stop the drawing when it beginns to overlap (drawing the same lines)
- by default when changing the small circle, put the drawing radius at the same value.
Best regards.
Please DON'T!!!
Very nice effects can be achieved this way as the smaller coin rolls faster, than the drawing radius...
if you Grow the coin to the radius, you will see that the effect is NOT the same...
Ok - thakns all for the usefull sugestions. I've already put in the pole length default, and the stop loop on closure - I wondered why my computer was starting to struggle, task manager showed all those little rollers eating up the cpu.
Mr Gee - I'm not sure what you mean by different sizes ??.
Also by multilpe rings, do you mean multiple moving circles rolling inside or outside the fixed circle, or one inside and one outside or a combination.
Also I have to be careful of pixel-estate since I want to allow the largest graph possible.
PS - Kkaus - I promise to put in some effort with the icon editor to make a nicer icon for this. Still - if anyone has a premade nice one I could borrow ???
Cableguy - I think klas intends that when you change to size of the movable circle you also reset the pole length equal to the new radius. You can still change the pole length again to be different to the new movable radius.
Certainly I have found myself having to make identical changes to the pole after altering the movbable circle more often than I've changed the movable radius and wanted to leave the pole length the same.
Mr Gee - I'm not sure what you mean by different sizes ??.
Also by multilpe rings, do you mean multiple moving circles rolling inside or outside the fixed circle, or one inside and one outside or a combination.
Also I have to be careful of pixel-estate since I want to allow the largest graph possible.
PS - Kkaus - I promise to put in some effort with the icon editor to make a nicer icon for this. Still - if anyone has a premade nice one I could borrow ???
Cableguy - I think klas intends that when you change to size of the movable circle you also reset the pole length equal to the new radius. You can still change the pole length again to be different to the new movable radius.
Certainly I have found myself having to make identical changes to the pole after altering the movbable circle more often than I've changed the movable radius and wanted to leave the pole length the same.
Have a look at specci48's link to wikipedia and you will understand Mr_Gee's suggestions.
- You can make a first draw with a certain configuration of the 3 parameters, press Stop
- Begin an other drawing, with an other color and an other configuration, without clearing the screen to superpose it to the first one.
- And a 3rd, 4th and so on.
In this case it would also be interesting to be able to choose the beginning point.
Best regards.
- You can make a first draw with a certain configuration of the 3 parameters, press Stop
- Begin an other drawing, with an other color and an other configuration, without clearing the screen to superpose it to the first one.
- And a 3rd, 4th and so on.
In this case it would also be interesting to be able to choose the beginning point.
Best regards.
Here the next version with a couple of tiny changes.
Bug fixes - form will now close properly
Added Features:
Exit button added
Changing parameters will not clear previous graph (use clear button to do this).
Lift/draw button added - if you want to make multiple changes to the parameters before starting a new graph then lift the pen, then hit draw to start drawing again when the parameters are all correct.
When resizing the movable radius the drawing radius will default to the new size (this drawing radius can be altered independently afterwards if required)
NB this default will be implemented optionally soon in an ini file.
1)TODO list
Option initialisation:
a) - colours
b)- drawing radius default
c) - start parameters
2) Colours:
a) pen
b) background
c) circles/pole ??? ( I think these should stay ghosted)
3) Better graphics - try to use setpixel to get a finer, more accurate line.
4) Graph movement
a) allow centre of drawing to move (Easy)
b) allow "slippy map" functionality and gesturing (Hard)
--------------------------------------------------
BTW This program started since discussing with my father about the envelope
of the sliding ladder situation (see ladder.sbp) we found that the astroid could also be produced by rolling circles.
PS - excuse the primitave nature of my coding - I may get better at it but after 30 years the chances are not all that good :sign0013:
Nick
Bug fixes - form will now close properly
Added Features:
Exit button added
Changing parameters will not clear previous graph (use clear button to do this).
Lift/draw button added - if you want to make multiple changes to the parameters before starting a new graph then lift the pen, then hit draw to start drawing again when the parameters are all correct.
When resizing the movable radius the drawing radius will default to the new size (this drawing radius can be altered independently afterwards if required)
NB this default will be implemented optionally soon in an ini file.
1)TODO list
Option initialisation:
a) - colours
b)- drawing radius default
c) - start parameters
2) Colours:
a) pen
b) background
c) circles/pole ??? ( I think these should stay ghosted)
3) Better graphics - try to use setpixel to get a finer, more accurate line.
4) Graph movement
a) allow centre of drawing to move (Easy)
b) allow "slippy map" functionality and gesturing (Hard)
--------------------------------------------------
BTW This program started since discussing with my father about the envelope
of the sliding ladder situation (see ladder.sbp) we found that the astroid could also be produced by rolling circles.
PS - excuse the primitave nature of my coding - I may get better at it but after 30 years the chances are not all that good :sign0013:
Nick
One more version - before colours appear
If the drawing is too slow on your device even after hitting + a few times then you can choose the otions form (while the pen is lifted) and drop the quality down from the default of 100 (to maybe 50 or so).
On this form you can also disable the "pole sync" which defaults the drawing radius to to movable radius whenever the movable radius is altered.
Colours will be next but will take some time as I want to make it simple yet flexable.
Nick
If the drawing is too slow on your device even after hitting + a few times then you can choose the otions form (while the pen is lifted) and drop the quality down from the default of 100 (to maybe 50 or so).
On this form you can also disable the "pole sync" which defaults the drawing radius to to movable radius whenever the movable radius is altered.
Colours will be next but will take some time as I want to make it simple yet flexable.
Nick
Here's a colour version (for desktop only).
Beware - changing background colour wipes out the drawing.
I've had to move the fixed circle to the forelayer so that it didn't intefere with the drawing bit I can't stop it flickering (any advice appreciated).
Next I'll do the boring stuff such as save/load/snap etc
I intend to allow save/store of a graph (A graph is the set of parameters used while drawing (i.e with pen down) since the last clear command)
E.G
cBack,I,10,40,10,cPen1:O,10,40,10,cPen2:O,10,40,30,cPen2
The graph will be saved, on closing to the savefile as "lastgraph". You can also save it to "favourite" or to a table of savedgraphs.
On startup, lastgraph will load and start drawing. You can reload and redraw any user-named graph from the savedlist or the favourite graph.
I'l also enable a snapshot of the screen, with or without the controls displayed, to disk or printer.
I'll define a file for the user preferences to be created on first execution and used thereafter to save session status etc.
Beware - changing background colour wipes out the drawing.
I've had to move the fixed circle to the forelayer so that it didn't intefere with the drawing bit I can't stop it flickering (any advice appreciated).
Next I'll do the boring stuff such as save/load/snap etc
I intend to allow save/store of a graph (A graph is the set of parameters used while drawing (i.e with pen down) since the last clear command)
E.G
cBack,I,10,40,10,cPen1:O,10,40,10,cPen2:O,10,40,30,cPen2
The graph will be saved, on closing to the savefile as "lastgraph". You can also save it to "favourite" or to a table of savedgraphs.
On startup, lastgraph will load and start drawing. You can reload and redraw any user-named graph from the savedlist or the favourite graph.
I'l also enable a snapshot of the screen, with or without the controls displayed, to disk or printer.
I'll define a file for the user preferences to be created on first execution and used thereafter to save session status etc.
