What is a non-concave and non-convex polygon called?
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I am writing a software function to plot the outer points of an n-sided polygon and I'm having trouble ensuring I use the correct terminology. The function I've written simply renders the calculated points of a predetermined polygon in two dimensional space. These polygons are neither convex nor concave and thus I believe the name I should give the function is Render Uniform Polygon; however, I believe uniform may not be the correct word and could end up in a debate over the name. The function itself performs three actions to achieve the goal:
- Calculate the angle of each point $theta_n$.
- Calculate the new position $P_n$.
- Render a 3px by 3px dot at the new position.
The math for calculating $theta_n$ is:
$$theta_n = frac{biggl(bigl(frac{360°}{p}bigr)n + phibiggr)pi}{180°}$$
Where:
$p$ is the number of points in the polygon.
$n$ is the current point.
$phi$ is the global rotation angle.
Once $theta_n$ has been calculated with the math above, I then use it to calculate the new position with the following:
$$P_{_n{x, y}} = C_{x, y} + (cos(theta_n), sin(theta_n))r$$
Where:
$P_n$ is current point's position.
$C_{x, y}$ is the center of the polygon.
$r$ is the radius of the polygon.
This method can be used to render any polygon with three sides or more, and since the radius is predefined there isn't a case where the polygon can be convex or concave.
What is a polygon that is neither convex nor concave called?
terminology polygons
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add a comment |
$begingroup$
I am writing a software function to plot the outer points of an n-sided polygon and I'm having trouble ensuring I use the correct terminology. The function I've written simply renders the calculated points of a predetermined polygon in two dimensional space. These polygons are neither convex nor concave and thus I believe the name I should give the function is Render Uniform Polygon; however, I believe uniform may not be the correct word and could end up in a debate over the name. The function itself performs three actions to achieve the goal:
- Calculate the angle of each point $theta_n$.
- Calculate the new position $P_n$.
- Render a 3px by 3px dot at the new position.
The math for calculating $theta_n$ is:
$$theta_n = frac{biggl(bigl(frac{360°}{p}bigr)n + phibiggr)pi}{180°}$$
Where:
$p$ is the number of points in the polygon.
$n$ is the current point.
$phi$ is the global rotation angle.
Once $theta_n$ has been calculated with the math above, I then use it to calculate the new position with the following:
$$P_{_n{x, y}} = C_{x, y} + (cos(theta_n), sin(theta_n))r$$
Where:
$P_n$ is current point's position.
$C_{x, y}$ is the center of the polygon.
$r$ is the radius of the polygon.
This method can be used to render any polygon with three sides or more, and since the radius is predefined there isn't a case where the polygon can be convex or concave.
What is a polygon that is neither convex nor concave called?
terminology polygons
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1
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All regular polygons are convex. As far as I know, a polygon that is neither convex nor concave is called "neither convex nor concave". I don't know of any special term for that.
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– Adrian Keister
Jan 21 at 18:22
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@AdrianKeister So simply Render Polygon should suffice in this case without causing any confusion?
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– PerpetualJ
Jan 21 at 18:23
1
$begingroup$
Sure! A regular polygon is a polygon, but not the reverse. So if you happen to be constructing regular polygons, aconstruct_polygon()
method is a fine name for that.
$endgroup$
– Adrian Keister
Jan 21 at 18:25
2
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For me, a concave polygon is one that has at least one angle greater than $pi$ and a convex one has no angles greater than $pi$. In that case there are no polygons that are neither concave nor convex.
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– Ross Millikan
Jan 21 at 18:25
$begingroup$
@RossMillikan: Excellent point, I agree!
$endgroup$
– Adrian Keister
Jan 21 at 18:26
add a comment |
$begingroup$
I am writing a software function to plot the outer points of an n-sided polygon and I'm having trouble ensuring I use the correct terminology. The function I've written simply renders the calculated points of a predetermined polygon in two dimensional space. These polygons are neither convex nor concave and thus I believe the name I should give the function is Render Uniform Polygon; however, I believe uniform may not be the correct word and could end up in a debate over the name. The function itself performs three actions to achieve the goal:
- Calculate the angle of each point $theta_n$.
- Calculate the new position $P_n$.
- Render a 3px by 3px dot at the new position.
The math for calculating $theta_n$ is:
$$theta_n = frac{biggl(bigl(frac{360°}{p}bigr)n + phibiggr)pi}{180°}$$
Where:
$p$ is the number of points in the polygon.
$n$ is the current point.
$phi$ is the global rotation angle.
Once $theta_n$ has been calculated with the math above, I then use it to calculate the new position with the following:
$$P_{_n{x, y}} = C_{x, y} + (cos(theta_n), sin(theta_n))r$$
Where:
$P_n$ is current point's position.
$C_{x, y}$ is the center of the polygon.
$r$ is the radius of the polygon.
This method can be used to render any polygon with three sides or more, and since the radius is predefined there isn't a case where the polygon can be convex or concave.
What is a polygon that is neither convex nor concave called?
terminology polygons
$endgroup$
I am writing a software function to plot the outer points of an n-sided polygon and I'm having trouble ensuring I use the correct terminology. The function I've written simply renders the calculated points of a predetermined polygon in two dimensional space. These polygons are neither convex nor concave and thus I believe the name I should give the function is Render Uniform Polygon; however, I believe uniform may not be the correct word and could end up in a debate over the name. The function itself performs three actions to achieve the goal:
- Calculate the angle of each point $theta_n$.
- Calculate the new position $P_n$.
- Render a 3px by 3px dot at the new position.
The math for calculating $theta_n$ is:
$$theta_n = frac{biggl(bigl(frac{360°}{p}bigr)n + phibiggr)pi}{180°}$$
Where:
$p$ is the number of points in the polygon.
$n$ is the current point.
$phi$ is the global rotation angle.
Once $theta_n$ has been calculated with the math above, I then use it to calculate the new position with the following:
$$P_{_n{x, y}} = C_{x, y} + (cos(theta_n), sin(theta_n))r$$
Where:
$P_n$ is current point's position.
$C_{x, y}$ is the center of the polygon.
$r$ is the radius of the polygon.
This method can be used to render any polygon with three sides or more, and since the radius is predefined there isn't a case where the polygon can be convex or concave.
What is a polygon that is neither convex nor concave called?
terminology polygons
terminology polygons
edited Jan 21 at 18:25
Adrian Keister
5,27371933
5,27371933
asked Jan 21 at 18:20


PerpetualJPerpetualJ
1767
1767
1
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All regular polygons are convex. As far as I know, a polygon that is neither convex nor concave is called "neither convex nor concave". I don't know of any special term for that.
$endgroup$
– Adrian Keister
Jan 21 at 18:22
$begingroup$
@AdrianKeister So simply Render Polygon should suffice in this case without causing any confusion?
$endgroup$
– PerpetualJ
Jan 21 at 18:23
1
$begingroup$
Sure! A regular polygon is a polygon, but not the reverse. So if you happen to be constructing regular polygons, aconstruct_polygon()
method is a fine name for that.
$endgroup$
– Adrian Keister
Jan 21 at 18:25
2
$begingroup$
For me, a concave polygon is one that has at least one angle greater than $pi$ and a convex one has no angles greater than $pi$. In that case there are no polygons that are neither concave nor convex.
$endgroup$
– Ross Millikan
Jan 21 at 18:25
$begingroup$
@RossMillikan: Excellent point, I agree!
$endgroup$
– Adrian Keister
Jan 21 at 18:26
add a comment |
1
$begingroup$
All regular polygons are convex. As far as I know, a polygon that is neither convex nor concave is called "neither convex nor concave". I don't know of any special term for that.
$endgroup$
– Adrian Keister
Jan 21 at 18:22
$begingroup$
@AdrianKeister So simply Render Polygon should suffice in this case without causing any confusion?
$endgroup$
– PerpetualJ
Jan 21 at 18:23
1
$begingroup$
Sure! A regular polygon is a polygon, but not the reverse. So if you happen to be constructing regular polygons, aconstruct_polygon()
method is a fine name for that.
$endgroup$
– Adrian Keister
Jan 21 at 18:25
2
$begingroup$
For me, a concave polygon is one that has at least one angle greater than $pi$ and a convex one has no angles greater than $pi$. In that case there are no polygons that are neither concave nor convex.
$endgroup$
– Ross Millikan
Jan 21 at 18:25
$begingroup$
@RossMillikan: Excellent point, I agree!
$endgroup$
– Adrian Keister
Jan 21 at 18:26
1
1
$begingroup$
All regular polygons are convex. As far as I know, a polygon that is neither convex nor concave is called "neither convex nor concave". I don't know of any special term for that.
$endgroup$
– Adrian Keister
Jan 21 at 18:22
$begingroup$
All regular polygons are convex. As far as I know, a polygon that is neither convex nor concave is called "neither convex nor concave". I don't know of any special term for that.
$endgroup$
– Adrian Keister
Jan 21 at 18:22
$begingroup$
@AdrianKeister So simply Render Polygon should suffice in this case without causing any confusion?
$endgroup$
– PerpetualJ
Jan 21 at 18:23
$begingroup$
@AdrianKeister So simply Render Polygon should suffice in this case without causing any confusion?
$endgroup$
– PerpetualJ
Jan 21 at 18:23
1
1
$begingroup$
Sure! A regular polygon is a polygon, but not the reverse. So if you happen to be constructing regular polygons, a
construct_polygon()
method is a fine name for that.$endgroup$
– Adrian Keister
Jan 21 at 18:25
$begingroup$
Sure! A regular polygon is a polygon, but not the reverse. So if you happen to be constructing regular polygons, a
construct_polygon()
method is a fine name for that.$endgroup$
– Adrian Keister
Jan 21 at 18:25
2
2
$begingroup$
For me, a concave polygon is one that has at least one angle greater than $pi$ and a convex one has no angles greater than $pi$. In that case there are no polygons that are neither concave nor convex.
$endgroup$
– Ross Millikan
Jan 21 at 18:25
$begingroup$
For me, a concave polygon is one that has at least one angle greater than $pi$ and a convex one has no angles greater than $pi$. In that case there are no polygons that are neither concave nor convex.
$endgroup$
– Ross Millikan
Jan 21 at 18:25
$begingroup$
@RossMillikan: Excellent point, I agree!
$endgroup$
– Adrian Keister
Jan 21 at 18:26
$begingroup$
@RossMillikan: Excellent point, I agree!
$endgroup$
– Adrian Keister
Jan 21 at 18:26
add a comment |
1 Answer
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As far as I can see your polygon is convex. It's a regular polygon whose vertices are equidistant on the circle with radius $r$ and center $C$.
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As far as I can see your polygon is convex. It's a regular polygon whose vertices are equidistant on the circle with radius $r$ and center $C$.
$endgroup$
add a comment |
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As far as I can see your polygon is convex. It's a regular polygon whose vertices are equidistant on the circle with radius $r$ and center $C$.
$endgroup$
add a comment |
$begingroup$
As far as I can see your polygon is convex. It's a regular polygon whose vertices are equidistant on the circle with radius $r$ and center $C$.
$endgroup$
As far as I can see your polygon is convex. It's a regular polygon whose vertices are equidistant on the circle with radius $r$ and center $C$.
answered Jan 21 at 18:25
lightxbulblightxbulb
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1
$begingroup$
All regular polygons are convex. As far as I know, a polygon that is neither convex nor concave is called "neither convex nor concave". I don't know of any special term for that.
$endgroup$
– Adrian Keister
Jan 21 at 18:22
$begingroup$
@AdrianKeister So simply Render Polygon should suffice in this case without causing any confusion?
$endgroup$
– PerpetualJ
Jan 21 at 18:23
1
$begingroup$
Sure! A regular polygon is a polygon, but not the reverse. So if you happen to be constructing regular polygons, a
construct_polygon()
method is a fine name for that.$endgroup$
– Adrian Keister
Jan 21 at 18:25
2
$begingroup$
For me, a concave polygon is one that has at least one angle greater than $pi$ and a convex one has no angles greater than $pi$. In that case there are no polygons that are neither concave nor convex.
$endgroup$
– Ross Millikan
Jan 21 at 18:25
$begingroup$
@RossMillikan: Excellent point, I agree!
$endgroup$
– Adrian Keister
Jan 21 at 18:26