#version 300 es
precision highp float;

in  vec2 uv;
out vec4 color;

uniform sampler2D sampler1;
uniform float     scale;

void main()
{
  vec4 tmp;
  if (scale > 1.0)
  {
    vec2 ts = vec2(textureSize(sampler1, 0));
    vec2 px = (uv - (0.5 / ts)) * ts;
    if (px.x < 0.0 || px.y < 0.0)
      discard;

    tmp = texelFetch(sampler1, ivec2(px), 0);
  }
  else
    tmp = texture(sampler1, uv);

  if (tmp.rgb == vec3(0.0, 0.0, 0.0))
    discard;

  color = tmp;
}