#version 430 core
layout (points) in;
layout (triangle_strip, max_vertices = 4) out;
in vec4 vParams [];
in vec2 vWinSize [];
out vec2 gTexPos;

uniform vec2 translation;
uniform float zoom;
uniform float rotation;

vec2 rotBy( float rot, vec2 v)
{
  return vec2 ( v.x * cos(rot) - v.y * sin(rot)
              , v.x * sin(rot) + v.y * cos(rot)
              );
        
}

void main()
{
  vec2 cPos = vec2(translation.x / 250 , translation.y /250 );
//  float zoom = vParams[0].w;
  float rot  = 0 - rotation;
      
  float x = vWinSize[0].x / (500*zoom) ;
  float y = vWinSize[0].y / (500*zoom) ;
  gTexPos = cPos + rotBy(-rot , vec2(x,y));
  gl_Position = vec4 (1,1,0.9,1);
  EmitVertex();
  gTexPos = cPos + rotBy(-rot , vec2(x,-y));
  gl_Position = vec4 (1,-1,0.9,1);
  EmitVertex();
  gTexPos = cPos + rotBy(-rot , vec2(-x,y));
  gl_Position = vec4 (-1,1,0.9,1);
  EmitVertex();
  gTexPos = cPos + rotBy(-rot , vec2(-x,-y));
  gl_Position = vec4 (-1,-1,0.9,1);
  EmitVertex();

  EndPrimitive();
}