// MVP matrices
uniform mat4 u_MMatrix;
uniform mat4 u_VMatrix;
uniform mat4 u_PMatrix;

// mesh
attribute vec4 a_Position;

void main(){

    // calculate MVP matrix
    mat4 u_MVMatrix = u_VMatrix * u_MMatrix;
    mat4 u_MVPMatrix = u_PMatrix * u_MVMatrix;

    // calculate rendered position
    gl_Position = u_MVPMatrix * a_Position;
    gl_PointSize = 15.0;
}