Re: Yertle the Turtle
I had been promoting Turtle Graphics in RR/LC for many years. Here are 4 implementation of Turtle Graphics in LC: http://jamesphurley.com/Revolution.html <http://jamesphurley.com/Revolution.html> Jim > > Message: 19 > Date: Mon, 30 Jan 2017 22:20:10 +0200 > From: Richmond Mathewson <richmondmathew...@gmail.com> > To: "u >> How to use LiveCode" <use-livecode@lists.runrev.com> > Subject: Yertle the Turtle > Message-ID: <aefb580f-87f2-cd2f-f22f-01e1dd90b...@gmail.com> > Content-Type: text/plain; charset=utf-8; format=flowed > > Having imported an SVG image of a tortoise into a stack . . . > > Being a fan of Seymour Papert . . . > > I thought I'd try and implement turtle graphics in Livecode. > > But came up against something awkward . . . > > [As a caveat, I should like to point out I don't know how the following > is implemented > in any other languages either] > > 1. Rotating my turtle widget is easy. > > 2. But telling the turtle to move forwards or backwards is not easy at all: > > In LOGO one can tell the turtle to turn left by, say, 30 degrees, and > then move forward 20 units. > > But in LiveCode, as far as I know, one can either move an object by > setting 2 coordinates, > or by 'set the loc'. > > 2.1. Now if I want my turtle, rotated at 30 degrees to move forward by > 20 units I will have to mess > around with SINE and COSINE and probably not end up with the turtle > moving exactly 20 units at 30 > degrees from the vertical. > > 2.2. I wonder how my turtle will be seen to draw a pen line from the two > ends of the "line". > > Richmond. > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
Hi All, Remember that Jim Hurley wrote a book: http://jamesphurley.com/RunRev/TurtlePhysicsText.doc and many stacks about Turtle Graphics: http://jamesphurley.com/Revolution.html Al ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
RE: Yertle the Turtle
>Mike Wrote: >Ah. Its sub pixel positioning. (a rose by any other name wouldn't be as alliterative as a ppp name) I banged my head against a wall for days trying to get smooth shading of 3d objects correct. (assembler on a 1980's ECL super computer) until the light went on and I used center pixel coordinates for the color calculations. The integer x/y pixel positions didn't cut it. Had to go center pixel floating point. Ralph DiMola IT Director Evergreen Information Services rdim...@evergreeninfo.net ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
nvm. ignore me. :) Something else entirely. (but the whole idea of tracking the coords separately still applies) (goes to bed) On Tue, Jan 31, 2017 at 2:57 PM, Mike Bonnerwrote: > Ah. Its sub pixel positioning. (a rose by any other name wouldn't be as > alliterative as a ppp name) > > On Tue, Jan 31, 2017 at 2:35 PM, Mike Bonner wrote: > >> Yeah, I think this is due to that change a while back (the partial pixel >> positioning stuff) it doesn't throw an error in your face if you set to a >> decimal coord anymore. >> >> >> >>> >>> Apparently fractional coordinates work fine, rounded reasonably well - >>> this works: >>> >>>set the left of btn 1 to 100.004 >>> >>> -- >>> Richard Gaskin >>> Fourth World Systems >>> Software Design and Development for the Desktop, Mobile, and the Web >>> >>> ambassa...@fourthworld.comhttp://www.FourthWorld.com >>> >>> ___ >>> use-livecode mailing list >>> use-livecode@lists.runrev.com >>> Please visit this url to subscribe, unsubscribe and manage your >>> subscription preferences: >>> http://lists.runrev.com/mailman/listinfo/use-livecode >>> >> >> > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
Ah. Its sub pixel positioning. (a rose by any other name wouldn't be as alliterative as a ppp name) On Tue, Jan 31, 2017 at 2:35 PM, Mike Bonnerwrote: > Yeah, I think this is due to that change a while back (the partial pixel > positioning stuff) it doesn't throw an error in your face if you set to a > decimal coord anymore. > > > >> >> Apparently fractional coordinates work fine, rounded reasonably well - >> this works: >> >>set the left of btn 1 to 100.004 >> >> -- >> Richard Gaskin >> Fourth World Systems >> Software Design and Development for the Desktop, Mobile, and the Web >> >> ambassa...@fourthworld.comhttp://www.FourthWorld.com >> >> ___ >> use-livecode mailing list >> use-livecode@lists.runrev.com >> Please visit this url to subscribe, unsubscribe and manage your >> subscription preferences: >> http://lists.runrev.com/mailman/listinfo/use-livecode >> > > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
Yeah, I think this is due to that change a while back (the partial pixel positioning stuff) it doesn't throw an error in your face if you set to a decimal coord anymore. > > Apparently fractional coordinates work fine, rounded reasonably well - > this works: > >set the left of btn 1 to 100.004 > > -- > Richard Gaskin > Fourth World Systems > Software Design and Development for the Desktop, Mobile, and the Web > > ambassa...@fourthworld.comhttp://www.FourthWorld.com > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
> Colin H. wrote: > I’m sure any system would not attempt to parse an infinite number of decimal > places. The turtle would probably be placed at 1.41421356237 pixels. If you > want to try more accurately than that, here’s the first million decimal > places: > https://apod.nasa.gov/htmltest/gifcity/sqrt2.1mil To make the confusion complete (or remove it): If the turtle of Pythagoras, sitting at (0,0) had to move sqrt(2) units, it would do that nevertheless *exactly*, crawling for example from (0,0) to (1,1). ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
I’m sure any system would not attempt to parse an infinite number of decimal places. The turtle would probably be placed at 1.41421356237 pixels. If you want to try more accurately than that, here’s the first million decimal places: https://apod.nasa.gov/htmltest/gifcity/sqrt2.1mil > On Jan 31, 2017, at 11:22 AM, Richmond Mathewson via use-livecode >wrote: > > If sqrt(2) is a bonkers number does anyone know how LOGO manages this? > > Richmond. > > On 1/31/17 5:36 pm, hh via use-livecode wrote: >>> Richmond wrote: >>> The problem is that (as far as I am aware) LiveCode cannot >>> move objects for fractions of pixels. >> Even if it could, this would be not enough, because sqrt(2) >> is an irrational number ;-) >> >> ___ >> use-livecode mailing list >> use-livecode@lists.runrev.com >> Please visit this url to subscribe, unsubscribe and manage your subscription >> preferences: >> http://lists.runrev.com/mailman/listinfo/use-livecode > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your subscription > preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
If sqrt(2) is a bonkers number does anyone know how LOGO manages this? Richmond. On 1/31/17 5:36 pm, hh via use-livecode wrote: Richmond wrote: The problem is that (as far as I am aware) LiveCode cannot move objects for fractions of pixels. Even if it could, this would be not enough, because sqrt(2) is an irrational number ;-) ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
Quentin Long wrote: > Suggestion for RM to try: Don't fuss about non-integer points—do all > the necessary calculations "under the hood", and just let point- > coördinates be assigned the resulting non-integer numbers as needed. > With any luck, LC will make this "just work" on your screen. Apparently fractional coordinates work fine, rounded reasonably well - this works: set the left of btn 1 to 100.004 -- Richard Gaskin Fourth World Systems Software Design and Development for the Desktop, Mobile, and the Web ambassa...@fourthworld.comhttp://www.FourthWorld.com ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
Suggestion for RM to try: Don't fuss about non-integer points—do all the necessary calculations "under the hood", and just let point-coördinates be assigned the resulting non-integer numbers as needed. With any luck, LC will make this "just work" on your screen. "Bewitched" + "Charlie's Angels" - Charlie = "At Arm's Length" Read the webcomic at [ http://www.atarmslength.net ]! If you like "At Arm's Length", support it at [ http://www.patreon.com/DarkwingDude ]. ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
Richmond Mathewson wrote: > Being a fan of Seymour Papert . . . > > I thought I'd try and implement turtle graphics in Livecode. Have you seen Jim Hurley's?: http://jamesphurley.com/Revolution.html -- Richard Gaskin Fourth World Systems Software Design and Development for the Desktop, Mobile, and the Web ambassa...@fourthworld.comhttp://www.FourthWorld.com ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
Whether you’re able to set subpixel or not, keep the intended location in variables, and add your move to the variables, then set the location of the turtle to the updated variables. > On Jan 31, 2017, at 2:41 AM, Richmond Mathewson via use-livecode >wrote: > > Thanks for the equations (I had in fact already worked those out), the > problem was > not that, the problem is that (as far as I am aware) LiveCode cannot move > objects > for fractions of pixels, so a move of , say, 30 forward at 30 degrees might > (and I haven't done > the Maths yet) either be 29, 30 or 32 units. > > Whether, in the great scheme of things this is that important is not clear. > > Richmond. > > On 1/31/17 8:22 am, Colin Holgate via use-livecode wrote: >> It is, as you said, going to need sin and cos. The X movement would be 30 * >> cos(37/180 * Pi), and the Y movement would be 30 * sin(37/180 * Pi), in your >> example case. >> >> >>> On Jan 30, 2017, at 11:14 PM, Richmond Mathewson via use-livecode >>> wrote: >>> >>> The problem is not with drawing the line. >>> >>> The problem is how, when the turtle's "nose" is pointing at, say, 37 >>> degrees from the vertical >>> one can get it to move FORWARD for 30 units. >>> >>> Richmond. >>> >>> On 1/30/17 11:46 pm, Tore Nilsen via use-livecode wrote: > 30. jan. 2017 kl. 21.20 skrev Richmond Mathewson via use-livecode > : > > 2.2. I wonder how my turtle will be seen to draw a pen line from the two > ends of the "line". If you would like the “turtle” to move to the points of the line then, lock screen, draw the line, hide the line and unlock the screen before you start moving the “turtle”. Then no-one will ever see the line and you can delete last graphic once the turtle has stopped moving. Regards Tore Nilsen ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode >>> ___ >>> use-livecode mailing list >>> use-livecode@lists.runrev.com >>> Please visit this url to subscribe, unsubscribe and manage your >>> subscription preferences: >>> http://lists.runrev.com/mailman/listinfo/use-livecode >> >> ___ >> use-livecode mailing list >> use-livecode@lists.runrev.com >> Please visit this url to subscribe, unsubscribe and manage your subscription >> preferences: >> http://lists.runrev.com/mailman/listinfo/use-livecode > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your subscription > preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
> Richmond wrote: > The problem is that (as far as I am aware) LiveCode cannot > move objects for fractions of pixels. Even if it could, this would be not enough, because sqrt(2) is an irrational number ;-) ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
If I recall correctly, you can SET a location now that is a fraction of a pixel.. Keep track of the decimals as your current location and use those numbers (within reason) as your start point, and continue onward. (think it was called partial pixel positioning?) While the actual location will be a full pixel, keeping track of the fractionals for your equations will keep things sympatico. On Tue, Jan 31, 2017 at 2:41 AM, Richmond Mathewson via use-livecode < use-livecode@lists.runrev.com> wrote: > Thanks for the equations (I had in fact already worked those out), the > problem was > not that, the problem is that (as far as I am aware) LiveCode cannot move > objects > for fractions of pixels, so a move of , say, 30 forward at 30 degrees > might (and I haven't done > the Maths yet) either be 29, 30 or 32 units. > > Whether, in the great scheme of things this is that important is not clear. > > Richmond. > > > On 1/31/17 8:22 am, Colin Holgate via use-livecode wrote: > >> It is, as you said, going to need sin and cos. The X movement would be 30 >> * cos(37/180 * Pi), and the Y movement would be 30 * sin(37/180 * Pi), in >> your example case. >> >> >> On Jan 30, 2017, at 11:14 PM, Richmond Mathewson via use-livecode < >>> use-livecode@lists.runrev.com> wrote: >>> >>> The problem is not with drawing the line. >>> >>> The problem is how, when the turtle's "nose" is pointing at, say, 37 >>> degrees from the vertical >>> one can get it to move FORWARD for 30 units. >>> >>> Richmond. >>> >>> On 1/30/17 11:46 pm, Tore Nilsen via use-livecode wrote: >>> 30. jan. 2017 kl. 21.20 skrev Richmond Mathewson via use-livecode < > use-livecode@lists.runrev.com>: > > 2.2. I wonder how my turtle will be seen to draw a pen line from the > two ends of the "line". > If you would like the “turtle” to move to the points of the line then, lock screen, draw the line, hide the line and unlock the screen before you start moving the “turtle”. Then no-one will ever see the line and you can delete last graphic once the turtle has stopped moving. Regards Tore Nilsen ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode >>> ___ >>> use-livecode mailing list >>> use-livecode@lists.runrev.com >>> Please visit this url to subscribe, unsubscribe and manage your >>> subscription preferences: >>> http://lists.runrev.com/mailman/listinfo/use-livecode >>> >> >> ___ >> use-livecode mailing list >> use-livecode@lists.runrev.com >> Please visit this url to subscribe, unsubscribe and manage your >> subscription preferences: >> http://lists.runrev.com/mailman/listinfo/use-livecode >> > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
Thanks for the equations (I had in fact already worked those out), the problem was not that, the problem is that (as far as I am aware) LiveCode cannot move objects for fractions of pixels, so a move of , say, 30 forward at 30 degrees might (and I haven't done the Maths yet) either be 29, 30 or 32 units. Whether, in the great scheme of things this is that important is not clear. Richmond. On 1/31/17 8:22 am, Colin Holgate via use-livecode wrote: It is, as you said, going to need sin and cos. The X movement would be 30 * cos(37/180 * Pi), and the Y movement would be 30 * sin(37/180 * Pi), in your example case. On Jan 30, 2017, at 11:14 PM, Richmond Mathewson via use-livecodewrote: The problem is not with drawing the line. The problem is how, when the turtle's "nose" is pointing at, say, 37 degrees from the vertical one can get it to move FORWARD for 30 units. Richmond. On 1/30/17 11:46 pm, Tore Nilsen via use-livecode wrote: 30. jan. 2017 kl. 21.20 skrev Richmond Mathewson via use-livecode : 2.2. I wonder how my turtle will be seen to draw a pen line from the two ends of the "line". If you would like the “turtle” to move to the points of the line then, lock screen, draw the line, hide the line and unlock the screen before you start moving the “turtle”. Then no-one will ever see the line and you can delete last graphic once the turtle has stopped moving. Regards Tore Nilsen ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
It is, as you said, going to need sin and cos. The X movement would be 30 * cos(37/180 * Pi), and the Y movement would be 30 * sin(37/180 * Pi), in your example case. > On Jan 30, 2017, at 11:14 PM, Richmond Mathewson via use-livecode >wrote: > > The problem is not with drawing the line. > > The problem is how, when the turtle's "nose" is pointing at, say, 37 degrees > from the vertical > one can get it to move FORWARD for 30 units. > > Richmond. > > On 1/30/17 11:46 pm, Tore Nilsen via use-livecode wrote: >>> 30. jan. 2017 kl. 21.20 skrev Richmond Mathewson via use-livecode >>> : >>> >>> 2.2. I wonder how my turtle will be seen to draw a pen line from the two >>> ends of the "line". >> If you would like the “turtle” to move to the points of the line then, lock >> screen, draw the line, hide the line and unlock the screen before you start >> moving the “turtle”. Then no-one will ever see the line and you can delete >> last graphic once the turtle has stopped moving. >> >> Regards >> Tore Nilsen >> ___ >> use-livecode mailing list >> use-livecode@lists.runrev.com >> Please visit this url to subscribe, unsubscribe and manage your subscription >> preferences: >> http://lists.runrev.com/mailman/listinfo/use-livecode > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your subscription > preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
K heres the required parts.. *## takes length and the angle in radians and returns vector as x,y offsets* function aLenToVector pLen pAngle return pLen * sin(pAngle),pLen * cos(pAngle) end aLenToVector *## takes degrees and changes to radians* function dToRadians pDegrees return pDegrees / 180 * pi end dToRadians With those 2 things, you should be able to move your turtle. On Mon, Jan 30, 2017 at 11:16 PM, Mike Bonnerwrote: > Yeah. Thats what my (as yet unrediscovered) library can help with. > > On Mon, Jan 30, 2017 at 11:14 PM, Richmond Mathewson via use-livecode < > use-livecode@lists.runrev.com> wrote: > >> The problem is not with drawing the line. >> >> The problem is how, when the turtle's "nose" is pointing at, say, 37 >> degrees from the vertical >> one can get it to move FORWARD for 30 units. >> >> Richmond. >> >> >> On 1/30/17 11:46 pm, Tore Nilsen via use-livecode wrote: >> >>> 30. jan. 2017 kl. 21.20 skrev Richmond Mathewson via use-livecode < use-livecode@lists.runrev.com>: 2.2. I wonder how my turtle will be seen to draw a pen line from the two ends of the "line". >>> If you would like the “turtle” to move to the points of the line then, >>> lock screen, draw the line, hide the line and unlock the screen before you >>> start moving the “turtle”. Then no-one will ever see the line and you can >>> delete last graphic once the turtle has stopped moving. >>> >>> Regards >>> Tore Nilsen >>> ___ >>> use-livecode mailing list >>> use-livecode@lists.runrev.com >>> Please visit this url to subscribe, unsubscribe and manage your >>> subscription preferences: >>> http://lists.runrev.com/mailman/listinfo/use-livecode >>> >> >> ___ >> use-livecode mailing list >> use-livecode@lists.runrev.com >> Please visit this url to subscribe, unsubscribe and manage your >> subscription preferences: >> http://lists.runrev.com/mailman/listinfo/use-livecode >> > > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
Yeah. Thats what my (as yet unrediscovered) library can help with. On Mon, Jan 30, 2017 at 11:14 PM, Richmond Mathewson via use-livecode < use-livecode@lists.runrev.com> wrote: > The problem is not with drawing the line. > > The problem is how, when the turtle's "nose" is pointing at, say, 37 > degrees from the vertical > one can get it to move FORWARD for 30 units. > > Richmond. > > > On 1/30/17 11:46 pm, Tore Nilsen via use-livecode wrote: > >> 30. jan. 2017 kl. 21.20 skrev Richmond Mathewson via use-livecode < >>> use-livecode@lists.runrev.com>: >>> >>> 2.2. I wonder how my turtle will be seen to draw a pen line from the two >>> ends of the "line". >>> >> If you would like the “turtle” to move to the points of the line then, >> lock screen, draw the line, hide the line and unlock the screen before you >> start moving the “turtle”. Then no-one will ever see the line and you can >> delete last graphic once the turtle has stopped moving. >> >> Regards >> Tore Nilsen >> ___ >> use-livecode mailing list >> use-livecode@lists.runrev.com >> Please visit this url to subscribe, unsubscribe and manage your >> subscription preferences: >> http://lists.runrev.com/mailman/listinfo/use-livecode >> > > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
The problem is not with drawing the line. The problem is how, when the turtle's "nose" is pointing at, say, 37 degrees from the vertical one can get it to move FORWARD for 30 units. Richmond. On 1/30/17 11:46 pm, Tore Nilsen via use-livecode wrote: 30. jan. 2017 kl. 21.20 skrev Richmond Mathewson via use-livecode: 2.2. I wonder how my turtle will be seen to draw a pen line from the two ends of the "line". If you would like the “turtle” to move to the points of the line then, lock screen, draw the line, hide the line and unlock the screen before you start moving the “turtle”. Then no-one will ever see the line and you can delete last graphic once the turtle has stopped moving. Regards Tore Nilsen ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
Somewhere around here I have a library that should help with your turtle moving. Will see if I can dig it up. On Mon, Jan 30, 2017 at 2:46 PM, Tore Nilsen via use-livecode < use-livecode@lists.runrev.com> wrote: > > > 30. jan. 2017 kl. 21.20 skrev Richmond Mathewson via use-livecode < > use-livecode@lists.runrev.com>: > > > > 2.2. I wonder how my turtle will be seen to draw a pen line from the two > ends of the "line". > > If you would like the “turtle” to move to the points of the line then, > lock screen, draw the line, hide the line and unlock the screen before you > start moving the “turtle”. Then no-one will ever see the line and you can > delete last graphic once the turtle has stopped moving. > > Regards > Tore Nilsen > ___ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Re: Yertle the Turtle
> 30. jan. 2017 kl. 21.20 skrev Richmond Mathewson via use-livecode >: > > 2.2. I wonder how my turtle will be seen to draw a pen line from the two ends > of the "line". If you would like the “turtle” to move to the points of the line then, lock screen, draw the line, hide the line and unlock the screen before you start moving the “turtle”. Then no-one will ever see the line and you can delete last graphic once the turtle has stopped moving. Regards Tore Nilsen ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
Yertle the Turtle
Having imported an SVG image of a tortoise into a stack . . . Being a fan of Seymour Papert . . . I thought I'd try and implement turtle graphics in Livecode. But came up against something awkward . . . [As a caveat, I should like to point out I don't know how the following is implemented in any other languages either] 1. Rotating my turtle widget is easy. 2. But telling the turtle to move forwards or backwards is not easy at all: In LOGO one can tell the turtle to turn left by, say, 30 degrees, and then move forward 20 units. But in LiveCode, as far as I know, one can either move an object by setting 2 coordinates, or by 'set the loc'. 2.1. Now if I want my turtle, rotated at 30 degrees to move forward by 20 units I will have to mess around with SINE and COSINE and probably not end up with the turtle moving exactly 20 units at 30 degrees from the vertical. 2.2. I wonder how my turtle will be seen to draw a pen line from the two ends of the "line". Richmond. ___ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode