I literally have no idea what I need to do to fix the code- I'm trying to send color information from javascript to webgl via shaders- I have a showing program- I basically want (at this point) to be able to print out my shader onto the screen, but all it does it show black :/

IN javascript:



Code :
            var count=0;
            var table = new Float32Array(128*4);
 
             for (var y = 0; y<(128*4); y+=1) {
 
                 var sig = .35;
 
 
                 table[count++] = sig;
                 table[count++] = sig;
                 table[count++] = sig;
                 table[count++] = 1;
 
 
 
 
             }
 
            //alert(count);
            //alert(table[101]);
 
 
            gl.activeTexture(gl.TEXTURE2);
 
 
            texturetab = gl.createTexture();
 
            gl.bindTexture(gl.TEXTURE_2D, texturetab);
 
            gl.pixelStorei(gl.UNPACK_ALIGNMENT, 1);
 
            gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 128*4, 1, 0,
 
                          gl.RGBA, gl.FLOAT, table);
 
            gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST);
 
            gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST);
 
            gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE);
 
            gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE);
 
 
            gl.useProgram(prog);
 
            //irrelevant code taken out for conciseness
 
            gl.uniform1i(gl.getUniformLocation(prog, "uTabSamp"), 2);




Fragment Shader:

Code :
 uniform sampler2D uTabSamp;
 
        const float d = 0.001953125; // 1./512. our delta (finite difference)
 
        void main(void) {
 
             sigmoid = texture2D(uTabSamp, vec2(2.5/128. ,.5)).r;
 
            //irrelevant code taken out
 
            gl_FragColor = vec4(texture2D(uTabSamp, vec2(3.0/128. ,.5)).r, 0,0,1. );
 
 
            }


Basically, I want to see that I'm at least getting some output on the screen from the texture- all I get is a black screen, though...