C Programming
Visual Basic Programming

How do you draw a circle using C or C plus plus without using the built in function?

8910

Top Answer
User Avatar
Wiki User
2010-01-06 01:04:44
2010-01-06 01:04:44

There are several options to draw a circle using C or C++ without the built-in functions...

<> <> <> <>

If you can draw a single pixel at a time, use a for loop to iterate Angle from 0 to 2*pi. Then plot a pixel with x=cos(Angle) and y=sin(Angle). Smaller steps will give better results. Lines from one point to the next may look nicer.

Generally, you can use a line from one pixel to the next to draw a polygon. The number of sides is determined by the number of steps from 0 to 2*pi. A circle is a polygon with an "infinite" number of sides (compared to the display resolution). Experiment with non-integral steps to see that the polygon can end at any place. Use an integral number of steps to end where the circle began. Start and stop at fractions of 2*pi, or step backwards, to create arcs. Speed up the code by using lookup tables to calculate sin() and cos(). Hint: they can be the same table, and don't need to be a complete 2*pi circle.

<> <> <> <>

You can also draw the circle without the sin() and cos() functions if you understand the trigonometry behind sin() and cos(). Recall that sin(theta) is radius / y, and cos(theta) is radius / x, given that x and y are the two sides of a right triangle and that radius is the hypotenuse.

By Pythagoream's theorem, x2 + y2 is radius2. It is then simple to solve for x or y, given the other along with radius. You also do not need to compute for the whole circle - you can compute for one quadrant, and generate the other three quadrants by symmetry. You generation loop would, for example, simply iterate from origin to radius as x by delta x, generating y, and reflecting that in the other three quadrants. You can also compute for one half of a quadrant, and use both symmetry and reflection to generate the other seven half quadrants.

12
๐Ÿ™
0
๐Ÿคจ
0
๐Ÿ˜ฎ
0
๐Ÿ˜‚
0

Related Questions

User Avatar

No, it is a shape rather than a function but it can be described using an algebraic function.

User Avatar

You would have to write your own code for a modulation (Matlab has a convolution function not in the tools), otherwise you can use its built in function in the signal processing toolbox.

User Avatar

plz as soon as possible give me the program for shorting an array in asscending order without using any sort function in c++

User Avatar

SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.SUM is a built-in function with Excel that has been specially designed to sum a range of cells. It just needs to know what the cells are and then it can add them all up. The method of doing that has been programmed into Excel by its developers. This leaves us with the simple task of using the function without needing to know the specifics of exactly how it does it.

User Avatar

Without any function is impossible. So I'll assume you mean any coded function, in which case the predefined function below is your answer.$string = strrev($string);

User Avatar

Sort of... A formula can use a function. A formula is a calculation on a spreadsheet. A function is a pre-defined formula built into Excel.An example of a function is SUM.An example of a formula using a function is =SUM(A1:A3).An example of a formula not using a function is =A5+C5

User Avatar

Both cut and copy are used in conjuction with paste. Think of some situations where you might use cut without using the paste function

User Avatar

That won't happen, you have to have a predefined putpixel (or something like that) function.

User Avatar

To find the area of a circle using the circumference, you need to use the formula Area=Circumference squared divided by four times pi. For this type of equation, pi would be equal to 3.14.

User Avatar

It can be done via its address, for example: void function (void (*callback)(void)) { (*callback)(); }

User Avatar

size_t strlen (const char *s) { const char *p= s-1; while (*++p); return p-s; }

User Avatar

You don't... I am a math teacher... you need to use the formula!

User Avatar

C programs do not function without functions.

User Avatar

a graph where a function is described without using specific values

User Avatar

The electricity used for it to function turns into heat, that's why computers have built in fans.

User Avatar

PHP has built-in one way hashing using the md5 function. Additional encryption capabilities are available using the Mcrypt extension.

User Avatar

The area of a circle is pi * radius2. If you already have the radius squared, you just have to multiply that by pi.


Copyright ยฉ 2020 Multiply Media, LLC. All Rights Reserved. The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply.