Help with Shader and Texture

[M3rs]

Hello SFML!
I'm having trouble getting my sf::Shader to work on a sf::RectangleShape that has a texture attached to it via setTexture( &texture).
Is there something I am missing in order to get that to work?

I'm using a simple fragment shader that I got from the forums somewhere here. Here is the shader:

(click to show/hide)

uniform sampler2D texture;
uniform vec3 light;
uniform vec4 lcolor;

void main() {
     float distance = sqrt(pow(gl_FragCoord.x - light.x, 2) +
                           pow(gl_FragCoord.y - light.y, 2));

     if(floor(light.x) == floor(gl_FragCoord.x) &&
        floor(light.y) == floor(gl_FragCoord.y))
       distance = 0.1;

     if(distance>light.z)
        distance = light.z;

     vec2 pos = gl_TexCoord[0].xy;

     //vec4 c2 = lcolor;
     //c2.a = 1.0 - (distance / light.z);
     // Why doesn't this work for texures???
     
     gl_FragColor = mix(texture2D(texture,pos),
                        lcolor,
                        1.0 - (distance/light.z));
     
}

And what happens is this:

(click to show/hide)

The rectangle shape on the left, with no texture, is properly lighted. On the right, with my wall.png as a texture, it still shown bright as day.

I'm pretty new to GLSL and wanted to use SFML because: 1. I really like it and have used it before, 2. OpenGL is a lot more code / scary to me.

Here is how I load the shader, create the rectangles and apply the texture:

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  sf::Shader shader;
 
  if (!shader.loadFromFile("light.frag", sf::Shader::Fragment))
    return -1;

  sf::RenderStates renderState;
  renderState.shader = &shader;

  shader.setParameter("texture", sf::Shader::CurrentTexture);


  sf::RectangleShape rect(sf::Vector2f(800,600));
 
  sf::RectangleShape r2(sf::Vector2f(200,200));
  r2.setPosition(200, 200);
  r2.setFillColor(sf::Color::Cyan);

  sf::RectangleShape r3(sf::Vector2f(320, 64));
  r3.setPosition(600, 100);
  sf::Texture t;
  t.loadFromFile("wall.png");
  r3.setTexture(&t);
 

Here is a snippet for the drawing:

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    window.draw(shadow(r2, em, sf::Color::Black));
    window.draw(r2, renderState);

    // why do the bricks not vanish?
    window.draw(shadow(r3, em, sf::Color::Black));
    window.draw(r3, renderState);

    window.display();

NB:
- The shadow method is what's creating those faux-hard shadows, again courtesy of the sfml forums (thanks, it's awesome, I have the link on my other computer).
- The "light" parameter for the shader is set earlier based on the mouse position.

Any help / advice would be much appreciated.

Thanks!