Why isn't this a square? LWJGL

Question

I have a basic LWJGL window set up and I am trying to draw a square using the glBegin(GL_QUADS) method. Square square = new Square(25, 25, 25), is

Answer 1

To draw a square around the point (x | y) you can calculate the four points that represent the corners of your square.

First you'll need your width to height ratio

float ratio = width / height

I will use a defaultSize for the length of the shortest path from the midpoint to any of the sides.

Then you can calculate four values like so:

float a = x + defaultSize 
float b = ratio * (y + defaultSize) 
float c = x - defaultSize 
float d = ratio * (y - defaultSize)

with which you can represent all four corners to draw your square with. Since GL_SQUAD is deprecated I'll use GL_TRIANGLE.

glBegin(GL_TRIANGLES);
glColor3f(red, green, blue);

// upper left triangle
glVertex2f(a, b);
glVertex2f(c, b);
glVertex2f(c, d);

 // lower right triangle
glVertex2f(a, b);
glVertex2f(c, d);
glVertex2f(a, d);

glEnd();

I don't know if this is the most performant or idiomatic way to do this since I just started exploring LWJGL.