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Slight Tangent Normal Map Confusion


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So, my mind is kinda messed up from this.  It seems to be the opposite of what I was expecting.
So when a normal map is generated from a black and white image and is set in tangent space does the "raised" elements look like they are going in or out on the normal map.

So when I generated my normal map initially I just used the values that I used where not inverted and I noticed that the elements seemed to be concave not convex, so I switched my x value to be inverted so on the Shader I output 1.0-x, y, 0.0, 1.0 respectively and it fixed the lighting direction on the mesh, but kept the look of the normal map as inverted like the example below on the left.

I then just for experimenting inverted the y as well, and it output the normal map on the right.

So now I am confused, which one is correct?  Cause that's confusing to me that the normal map on the left will look the same with 1.0-x, y will look the same as x,y on the normal map image, but when actually applied seems to invert the bump.
Here is a example:


const NormalmapGenerator0 =
`varying vec2 vUV;

uniform vec2 textureSize;
uniform sampler2D textureSampler;

void main(){
    vec2 unit = vec2(1.0)/textureSize;
    float x = ((texture2D(textureSampler, vUV+(unit*vec2(-1.,0.))).r
    -texture2D(textureSampler, vUV+(unit*vec2(1.,0.))).r)+1.)*0.5;
    float y = ((texture2D(textureSampler, vUV+(unit*vec2(0.,1.))).r
    -texture2D(textureSampler, vUV+(unit*vec2(0.,-1.))).r)+1.)*0.5;
#if defined(invertDepth)
    	gl_FragColor = vec4(x, y, 1.0, 1.0);
	gl_FragColor = vec4(1.0-x, 1.0-y, 1.0, 1.0);


There is the shader. So the question comes up now, which is the correct output, if different once will produce the same results but seemly should not... *BRAIN EXPLODING* 

vec4(x, y, 1.0, 1.0);
vec4(1.0-x, y, 1.0, 1.0);
vec4(x,1.0- y, 1.0, 1.0);
vec4(1.0-x,1.0- y, 1.0, 1.0);

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