How many sides should a circular sector have?

[BeachThunder]

This question is something that keeps floating around inside my head.

 

I know it's a very "how long is a piece of string" kinda question. But do people have any good rules of thumb for how many sides a circular sector should have vs. the size of the sector?
 

[RataUnderground]

I tend to use geometry without much detail in my levels, and I rarely use circles, but when I do use them I usually stick to 12 faces, since with those numbers and a 15 degree rotation you always have flat faces (not corners) in the orthogonal directions.

[Stabbey]

It entirely depends on how important the room appearing circular is for you, the effect you're trying to achieve. The more sections, the greater the appearance of a true circle. There are limits, of course, especially if trying to work within a 128 visplane vanilla limit.

[indigotyrian]

for me it depends on the size of the circle. If it's smaller than 128px I use 8 sides, beyond that I use 16. I may do 32 if it's a particularly big circle. I try really hard to have the length of all linedefs in the circle add up to a multiple of the pixel width of the texture I'll be using. I don't like having especially finely-detailed sectors in doom since its kind of unfitting with the general graphical fidelity of the game, but I do like using powers of 2 a lot especially in manmade/constructed spaces.

Edited August 25, 2023 by indigotyrian

[plums]

22 minutes ago, indigotyrian said:

I try really hard to have the length of all linedefs in the circle add up to a multiple of the pixel width of the texture I'll be using

I made a post about this awhile ago, though I didn't explain things too clearly, especially when I get into polygons instead of circles. I should maybe make an improved version? Anyhow you can use math to figure out what radius you want to get a particular circumference of the circle and it's probably easier than just guessing at it or fumbling with linedefs until you get the right result.

[indigotyrian]

13 minutes ago, plums said:

I made a post about this awhile ago, though I didn't explain things too clearly, especially when I get into polygons instead of circles. I should maybe make an improved version? Anyhow you can use math to figure out what radius you want to get a particular circumference of the circle and it's probably easier than just guessing at it or fumbling with linedefs until you get the right result.

 

That's useful! But one reason I stick with powers of 2 is that they gel rather nicely with texture lengths for quick math. For example, if I want a pillar that's around 64 units wide, I can make an 8-sided polygon with 24-unit sides. Eight 24-unit sides is 192 units total, which divides evenly into a 64px wide texture for three clean repetitions.

Edited August 25, 2023 by indigotyrian

[Kappes Buur]

My go-to mode for drawing circular sectors is the Draw Ellipse Mode,

for ellipses

 

 

or circles

 

 

for circles I usually use 24 vertices, or any multiple of 4, which tents to

make all linedefs the same length, which has some benefits along the way

 

or use the Draw Curve Mode which makes smooth bezier curves

 

 

and perhaps the Randomize control for other edge effects

 

 

Edited August 25, 2023 by Kappes Buur

[LoatharMDPhD]

// 9 minimum 13 optimal, over 22 and you're just bragging...

[Fonze]

I think the number of lines doesn't matter so much as the visual distinction of doom's faux lighting on the orthogonal lines breaking the visual of a "circle" by implying that flat lines make it up. Other than that, idk how many people are gonna notice while playing a new map if a particular sector isn't perfectly round, or is some geometric shape that isn't exactly a circle. So that would be my take, but as with any art just make sure it looks good to you 😀

[rita remton]

i just learnt about this several weeks ago in the ramp2023 discord server, taught by @LordEntr0py. the answer is 24 sides. reason:

• linedefs in udb is rotated at intervals of 15° (udmf). if a mapper draws a linedef, copy paste, rotates it then sets it place, it would make a circle with 24 sides. very handy if a mapper decides to add more linedefs later within the circle since everything is aligned nicely. personal note: this does not apply to vanilla doom where the vertices must be set according to the 1x1mu minimum grid size, causing the circle to have a wonky shape if the size of the circle is small. not noticeable if the circle is large.
• personal reason: the circle could be divided equally by 3, 4, 6, 8, and 12. this makes it ideal if one were to build a round roof (3d floor) with the best amount of supporting beams, or a clock face on the floor.

just my 2 cents. hope this helps :)

[NiGHTS108]

Of course, it depends on what exactly the circle is for, and I don't think it really matters a ton outside of specific instances. Truthfully, I just use 10 sides because it's the default on UDB, lol.

[NightRiding Doom]

My go to for circles is between 16 and 24. Highest I went was 128

Edited September 6, 2023 by tumedaskihutaja_37685