#version 330 core
layout (location = 0) in vec3 aPos;
// position has attribute position 0
layout (location = 1) in vec3 aColor; // color has attribute position 1
out vec3 vertexColor; // output a color to fragment shader
void main()
{
   gl_Position = vec4(aPos, 1.0);
   vertexColor = aColor;
}