Empathy List Archives

K

kintel

Wed, Jan 21, 2015 12:13 AM

It looks ok to me.
FYI: rotate([45,45,45]) is equivalent to rotate([45,0,0]) rotate([0,45,0])
rotate([0,0,45]), so you can play with each component to discover why it
works as it does.
This type of rotation can be a bit counter intuitive if you're not used to
rotating stuff in 3D ;)

-Marius

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It looks ok to me. FYI: rotate([45,45,45]) is equivalent to rotate([45,0,0]) rotate([0,45,0]) rotate([0,0,45]), so you can play with each component to discover why it works as it does. This type of rotation can be a bit counter intuitive if you're not used to rotating stuff in 3D ;) -Marius -- View this message in context: http://forum.openscad.org/Do-3-45-turns-of-a-line-in-the-axis-make-it-a-space-diagonal-to-that-octant-tp11132p11159.html Sent from the OpenSCAD mailing list archive at Nabble.com.

NH

nop head

Wed, Jan 21, 2015 12:32 AM

Isn't it the other way round ?, i.e. X first Z last so

rotate([0,0,45]) rotate([0,45,0]) rotate([45,0,0])

On 21 January 2015 at 00:13, kintel marius@kintel.net wrote:

It looks ok to me.
FYI: rotate([45,45,45]) is equivalent to rotate([45,0,0]) rotate([0,45,0])
rotate([0,0,45]), so you can play with each component to discover why it
works as it does.
This type of rotation can be a bit counter intuitive if you're not used to
rotating stuff in 3D ;)

-Marius

--
View this message in context:
http://forum.openscad.org/Do-3-45-turns-of-a-line-in-the-axis-make-it-a-space-diagonal-to-that-octant-tp11132p11159.html
Sent from the OpenSCAD mailing list archive at Nabble.com.

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Isn't it the other way round ?, i.e. X first Z last so rotate([0,0,45]) rotate([0,45,0]) rotate([45,0,0]) On 21 January 2015 at 00:13, kintel <marius@kintel.net> wrote: > It looks ok to me. > FYI: rotate([45,45,45]) is equivalent to rotate([45,0,0]) rotate([0,45,0]) > rotate([0,0,45]), so you can play with each component to discover why it > works as it does. > This type of rotation can be a bit counter intuitive if you're not used to > rotating stuff in 3D ;) > > -Marius > > > > > -- > View this message in context: > http://forum.openscad.org/Do-3-45-turns-of-a-line-in-the-axis-make-it-a-space-diagonal-to-that-octant-tp11132p11159.html > Sent from the OpenSCAD mailing list archive at Nabble.com. > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >

MK

Marius Kintel

Wed, Jan 21, 2015 1:11 AM

On Jan 20, 2015, at 19:32 PM, nop head nop.head@gmail.com wrote:

Isn't it the other way round ?, i.e. X first Z last so

rotate([0,0,45]) rotate([0,45,0]) rotate([45,0,0])

You’re right, my head was on backwards.

-Marius

On Jan 20, 2015, at 19:32 PM, nop head <nop.head@gmail.com> wrote: > Isn't it the other way round ?, i.e. X first Z last so > > rotate([0,0,45]) rotate([0,45,0]) rotate([45,0,0]) > You’re right, my head was on backwards. -Marius

B

Bananapeel

Wed, Jan 21, 2015 3:08 PM

Out of curiousity, is there a way to figure out how to rotate to get what
GeeBee expects?

:)

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Out of curiousity, is there a way to figure out how to rotate to get what GeeBee expects? :) -- View this message in context: http://forum.openscad.org/Do-3-45-turns-of-a-line-in-the-axis-make-it-a-space-diagonal-to-that-octant-tp11132p11182.html Sent from the OpenSCAD mailing list archive at Nabble.com.

NH

nop head

Wed, Jan 21, 2015 3:45 PM

I think not if I understand the question
, because the answer to "Do 3 45° turns of a line in the axis make it a
space diagonal to that octant" is no.

It takes only two rotations, one of 45 and the other of atan(sqrt(0.5)) for
the reason you showed above.

cube(50, center = true);

hull() {

sphere();

rotate([0,-atan(sqrt(0.5)), 45])

 translate([100, 0, 0])

     sphere();

}

On 21 January 2015 at 15:08, Bananapeel lunatica.xiaoyu@gmail.com wrote:

Out of curiousity, is there a way to figure out how to rotate to get what
GeeBee expects?

:)

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I think not if I understand the question , because the answer to "Do 3 45° turns of a line in the axis make it a space diagonal to that octant" is no. It takes only two rotations, one of 45 and the other of atan(sqrt(0.5)) for the reason you showed above. cube(50, center = true); hull() { sphere(); rotate([0,-atan(sqrt(0.5)), 45]) translate([100, 0, 0]) sphere(); } On 21 January 2015 at 15:08, Bananapeel <lunatica.xiaoyu@gmail.com> wrote: > Out of curiousity, is there a way to figure out how to rotate to get what > GeeBee expects? > > :) > > > > > -- > View this message in context: > http://forum.openscad.org/Do-3-45-turns-of-a-line-in-the-axis-make-it-a-space-diagonal-to-that-octant-tp11132p11182.html > Sent from the OpenSCAD mailing list archive at Nabble.com. > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >

B

Bananapeel

Wed, Jan 21, 2015 4:36 PM

Thank you, atan is the function I was looking for.

After thinking about it, I have understood that it is not possible to rotate
a cube in the way I was visualizing. In that case you would need a different
shape than a cube.

side = 10;
side_half = side/2;
opposite_over_adjacent = side_half / (side_half*sqrt(2));

rotate([45, atan(opposite_over_adjacent), 0])
cube([side, side, side], center = true);

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Sent from the OpenSCAD mailing list archive at Nabble.com.

Thank you, atan is the function I was looking for. After thinking about it, I have understood that it is not possible to rotate a cube in the way I was visualizing. In that case you would need a different shape than a cube. side = 10; side_half = side/2; opposite_over_adjacent = side_half / (side_half*sqrt(2)); rotate([45, atan(opposite_over_adjacent), 0]) cube([side, side, side], center = true); -- View this message in context: http://forum.openscad.org/Do-3-45-turns-of-a-line-in-the-axis-make-it-a-space-diagonal-to-that-octant-tp11132p11184.html Sent from the OpenSCAD mailing list archive at Nabble.com.

C

clothbot

Wed, Jan 21, 2015 5:55 PM

Side note: The atan2 function may be (more) useful as it takes into
consideration the sign of the y & x values.

See
http://en.wikibooks.org/wiki/OpenSCAD_User_Manual/The_OpenSCAD_Language#atan2

Andrew.

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Side note: The atan2 function may be (more) useful as it takes into consideration the sign of the y & x values. See http://en.wikibooks.org/wiki/OpenSCAD_User_Manual/The_OpenSCAD_Language#atan2 Andrew. -- View this message in context: http://forum.openscad.org/Do-3-45-turns-of-a-line-in-the-axis-make-it-a-space-diagonal-to-that-octant-tp11132p11185.html Sent from the OpenSCAD mailing list archive at Nabble.com.

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Re: [OpenSCAD] Do 3 45° turns of a line in the axis make it a space diagonal to that octant?