attribute vec4 a_Position;
uniform float u_SinB, u_CosB;

void main(){
  gl_Position.x = a_Position.x * u_CosB - a_Position.y * u_SinB;
  gl_Position.y = a_Position.x * u_SinB + a_Position.y * u_CosB;
  gl_Position.z = a_Position.z;
  gl_Position.w = a_Position.w;
  gl_PointSize = 10.0;
}

precision mediump float;
uniform vec4 u_FragColor;
void main(){
  gl_FragColor = u_FragColor;
}