Opengl/glsl : Pass float array to shader by texture - opengl

Question

I am trying to pass a float* that contains 128*128 float to a shader. Since this array is too big, I am trying to pass by a texture to get my float* in my shader. The problem is I don't know how to use this array inside my shader.
I print my float* before sending it to my shader, and It contains number between -1 and 1.
My goal is to simulate waves on water with perlin noise, so my array of float is perlin noises.
So I instantiate my noise texture like this :
_perlin_noise = new float[_dimension * _dimension];
//... I put float inside my _perlin_noise variable
//Then I instantiate my texture :
glGenTextures(1, &_perlin_noise_text);
glBindTexture(GL_TEXTURE_2D, _perlin_noise_text);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, GL_R32F, _dimension, _dimension, 0,
GL_RED, GL_FLOAT, _perlin_noise);
glActiveTexture(0);
glBindTexture(GL_TEXTURE_2D, 0);
My water use two textures : One texture is full blue, the other is a texture of foam.
So now I have a third texture that is my perlin noise. And I want to ajust the height of my vertices by perlin noise.
So before anything, I alocate uniform variable to my shader like this :
main_water_shader->use();
glUniform1i(glGetUniformLocation(main_water_shader->getProgram(), "main_water_texture"), 0);
glUniform1i(glGetUniformLocation(main_water_shader->getProgram(), "foam_texture"), 1);
glUniform1i(glGetUniformLocation(main_water_shader->getProgram(), "perlin_noise"), 2);
Then I want to ajust vertices's height in my vertex shader, but I don't know how to do it. I tried to do that in my vertex shader :
uniform sampler2D perlin_noise;
//some other uniform...
void main()
{
//calculating vertex height
float height = float( texture2D(perlin_noise, vec2(x, y)) );
vec3 new_vertex_position = vertex_position;
new_vertex_position.y = height;
//Standard stuff
vs_position = vec4(ModelMatrix * vec4(new_vertex_position, 1.f)).xyz;
vs_texcoord = vec2(vertex_texcoord.x, vertex_texcoord.y );
vs_normal = mat3(ModelMatrix) * vertex_normal;
gl_Position = ProjectionMatrix * ViewMatrix * ModelMatrix * vec4(new_vertex_position, 1.f);
}
Nothing change, the height of my vertices is still the same. And if I try to display my perlin_noise texture in my fragment shader onto a plan, I get this :
You can see my plane (which is very large) with a black and white texture on it that is repeated. So I guess my perlin_noise texture does contains something (even if it is a bit weird), but I can't figure out how to use it in my vertex shader.
EDIT : In my screenshoot, I also use a vertex shader with height ajusted with perlin noise, but as you can see, my plane is plane, so It does not seems to work.
EDIT2 : If I'm not clear enough, tell me