Shaders Creating multiple simple light sources using shaders

[Dudeless]

Hi,

I have written a shader code that creates a ball of non-darkness (I don't know how else I should put this) around one of my objects. You can see it in this picture below:

To do that, I created a completely black, rectangle object (whose size is the same room's) and put it on a layer above everything. Then, I wrote this code in the fragment shader (and wrote the necessary codes to the "draw" event):

varying vec2 v_vTexcoord;
varying vec4 v_vColour;
varying vec2 v_vPosition;

uniform float x_player;
uniform float y_player;




void main()
{
    gl_FragColor = v_vColour * texture2D( gm_BaseTexture, v_vTexcoord );
    gl_FragColor = vec4(gl_FragColor.rgb,(abs(distance(vec2(x_player,y_player),v_vPosition)/512.0)));
}

Until now, there is no problem. It works as it should. But I want to add multiple light sources (like torches etc.) which create "balls of non-darkness" simultaneously. But I couldn't figure out a way. I am very new at writing shader codes, so I would be very glad if you could help me with this.
Thanks in advance~

 

[Fanatrick]

You can change the uniform type from a single float to an array and pass the coords that way.

 

[kburkhart84]

You could also forget the shader and just use surfaces the way this was done before we even got access to shaders. There are plenty of tutorials out there on the technique.