2D Fragment Shader rendering Blue instead of White

Hi all,

new to shaders so please take it easy on me!

I am trying to implement filters to simulate colour blindness. It should be a simple linear transformation, but for some reason the shader is out putting blue instead of white.

I've tried a few different things and so far i am quite confused!

`void fragment(){
// start off with white
	vec4 curr_col = vec4(1.0, 1.0, 1.0, 1.0);

//precomputed transformation to simulate red colour blindess
	mat3 vienot_protan_from_lRGB = mat3(vec3( 0.11238, 0.88762, 0.00000),
								vec3(0.11238, 0.88762, -0.00000),
								vec3(0.00401, -0.00401, 1.00000));

//	testing manual matrix multiplication. 
	curr_col = vec4(0.11238 + 0.88762,
					0.11238 + 0.88762,
					0.00401 - 0.00401 + 1.00000,
					1.0);
//  outputs correctly and renders white
//	COLOR = curr_col;

//	my implementation of matrix multiplcation
//	vec3 result = vec3(
//						vienot_protan_from_lRGB[0][0]*COLOR.r +
//						vienot_protan_from_lRGB[1][0]*COLOR.g +
//						vienot_protan_from_lRGB[2][0]*COLOR.b,
//						vienot_protan_from_lRGB[0][1]*COLOR.r +
//						vienot_protan_from_lRGB[1][1]*COLOR.g +
//						vienot_protan_from_lRGB[2][1]*COLOR.b,
//						vienot_protan_from_lRGB[0][2]*COLOR.r +
//						vienot_protan_from_lRGB[1][2]*COLOR.g +
//						vienot_protan_from_lRGB[2][2]*COLOR.b);
//
//	incorrectly outputs blue
//	COLOR = vec4(result, COLOR.a);

// GLSL built in matrix multiplcation
	vec4 result = vec4(vienot_protan_from_lRGB * curr_col.rgb, curr_col.a);
//	incorrectly outputs blue
	COLOR = result;`

current output, should be a white square instead!

Cheers,
DD