l need draw many point for a circle,or have some simple ways?
0
If l want to draw a circle.How to do it?
Started by bluepig.man, Oct 30 2012 07:05 PM
4 replies to this topic
#2 Members - Reputation: 1990
Posted 31 October 2012 - 02:56 AM
Everything you draw on a computer (other than a single point) ends up as many points.
Search for "Bresenham circle" for a discrete approach; alternatively, you can tessellate (or subdivide) your circle into line segments that approximate the circle and draw those with a line algorithm.
Search for "Bresenham circle" for a discrete approach; alternatively, you can tessellate (or subdivide) your circle into line segments that approximate the circle and draw those with a line algorithm.
Niko Suni
Software developer
Software developer
#4 Members - Reputation: 1054
Posted 01 November 2012 - 01:58 PM
Every point on a circle can be calculated by:
x = radius * cos(theta);
y = radius * sin(theta);
Where, theta is all values between 0 and 2PI, and radius is greater than zero.
So, to draw a circle, you can could either plot a bunch of pixels to the screen at the X,Y coordinates as you loop through every value of theta...
or you could draw line segments between each of the X/Y value pairs for all values of theta.
x = radius * cos(theta);
y = radius * sin(theta);
Where, theta is all values between 0 and 2PI, and radius is greater than zero.
So, to draw a circle, you can could either plot a bunch of pixels to the screen at the X,Y coordinates as you loop through every value of theta...
or you could draw line segments between each of the X/Y value pairs for all values of theta.
Eric Nevala
Hobby: Game Developer
Currently employed as: Sr. Sharepoint Developer in Afghanistan
Hobby: Game Developer
Currently employed as: Sr. Sharepoint Developer in Afghanistan
