Set a pen on painter painter.setPen(Qt::NoPen); Qt has 'brush' for filling figures, and 'pen' for drawing lines and outlines....

I dont know what is your dataset is... So I have created random one... I used plotrix package for this... library(plotrix) df = data.frame(x=sample(1:25),y=sample(1:25,replace=T,25)) plot(df,col='blue') draw.ellipse(x= c(15), y= c(15), c(4), c(3), border = 'black', lwd = 2) draw.ellipse(x= c(15), y= c(15), c(5), c(4), border = 'green', lwd = 2) draw.ellipse(x=...

c++,opengl,ellipse,drawellipse

I think you're encountering overflow. I played with your code. While I never saw exactly the same "lemon" type shapes from your pictures, things definitely fell apart at large sizes, and it was caused by overflowing the range of the int variables used in the code. For example, look at...

You're actually pretty close; you made a small mistake in the definition of the x value and simply need to swap data(i,8) with data(i,7). i.e. change that line: x = data(i,7)/2 * cos(theta) * cos(data(i,9)) - data(i,8)/2 * sin(theta) * sin(data(i,9)) + data(i,5); for that one: x = data(i,8)/2 *...