Shader attributes for mesh(int/uint)

Questions
#1

Can i use uint/int attributes in shader? (for mesh)

I have that buffer. I try to replace {HASH_POSITION, dmBuffer::VALUE_TYPE_FLOAT32, 3}, vs VALUE_TYPE_UINT8 or VALUE_TYPE_UINT16

const dmBuffer::StreamDeclaration chunk_buffer_decl[] = {
    {HASH_POSITION, dmBuffer::VALUE_TYPE_FLOAT32, 3},
    // instead of normal can use one float value for fake sun light
    {HASH_NORMAL, dmBuffer::VALUE_TYPE_FLOAT32, 3},
    {HASH_TEXCOORD0, dmBuffer::VALUE_TYPE_FLOAT32, 2},
    {HASH_CHUNK_DATA_POS_X, dmBuffer::VALUE_TYPE_UINT8, 1},
    {HASH_CHUNK_DATA_POS_Y, dmBuffer::VALUE_TYPE_UINT16, 1},
    {HASH_CHUNK_DATA_POS_Z, dmBuffer::VALUE_TYPE_UINT8, 1},
};

This is my shader. When i use float attribute highp float cd_pos_x; it worked. But when i try to use int/uint it not worked.(i get artifacts in shader)

attribute highp vec3 position;
attribute mediump vec3 normal;
attribute mediump vec2 texcoord0;
attribute highp float cd_pos_x;
attribute highp float cd_pos_y;
attribute highp float cd_pos_z;
// attribute lowp vec3 color;

uniform highp mat4 mtx_worldview;
uniform highp mat4 mtx_world;
// uniform highp mat4 mtx_view;
uniform highp mat4 mtx_proj;
uniform highp mat4 mtx_normal;

varying highp vec3 var_world_position;
varying mediump vec3 var_world_normal;
varying highp vec3 var_position;
varying mediump vec3 var_normal;
varying mediump vec2 var_texcoord0;
// varying lowp vec3 var_color;

//
// WebGL 1.0 / OpenGL ES 2.0 don't have "transpose" and "inverse" functions.
//
mat3 mat_transpose(mat3 m) {
    return mat3(m[0][0], m[1][0], m[2][0],
        m[0][1], m[1][1], m[2][1],
        m[0][2], m[1][2], m[2][2]);
}

mat3 mat_inverse(mat3 m) {
    float a00 = m[0][0], a01 = m[0][1], a02 = m[0][2];
    float a10 = m[1][0], a11 = m[1][1], a12 = m[1][2];
    float a20 = m[2][0], a21 = m[2][1], a22 = m[2][2];

    float b01 = a22 * a11 - a12 * a21;
    float b11 = -a22 * a10 + a12 * a20;
    float b21 = a21 * a10 - a11 * a20;

    float det = a00 * b01 + a01 * b11 + a02 * b21;

    return mat3(b01, (-a22 * a01 + a02 * a21), (a12 * a01 - a02 * a11),
        b11, (a22 * a00 - a02 * a20), (-a12 * a00 + a02 * a10),
        b21, (-a21 * a00 + a01 * a20), (a11 * a00 - a01 * a10)) / det;
}
//
//
//

void main()
{
    vec3 pos = vec3(cd_pos_x, cd_pos_y, cd_pos_z);
    var_world_position = (mtx_world * vec4(pos, 1.0)).xyz;
    var_world_normal = normalize(mat_transpose(mat_inverse(mat3(mtx_world))) * normal.xyz);

    vec4 p = mtx_worldview * vec4(pos, 1.0);
    var_position = p.xyz;
    var_normal = normalize(mat3(mtx_normal) * normal.xyz);
    var_texcoord0 = texcoord0;

    gl_Position = mtx_proj * p;
}