How to get color value from color frame at a point position

[obypix]

From the following example code on generating a point cloud:

rs2::frameset frames = pipe.wait_for_frames();
auto color = frames.get_color_frame();
if (!color)
    color = frames.get_infrared_frame();
rs2::pointcloud pc;
pc.map_to(color);
rs2::depth_frame depth = frames.get_depth_frame();
rs2::points points;
points = pc.calculate(depth);
auto vertices = points.get_vertices();              // get vertices
auto tex_coords = points.get_texture_coordinates(); // and texture coordinates

Can the color be obtained from the color frame, using the texture coordinates? I tried the following as an example:

rs2::video_frame vf = color;
const void* vf_data = vf.get_data();
unsigned short* vf_data_us = (unsigned short*) vf_data;

int color_width = color.get_width();
int color_height = color.get_height();

        int ix = (int) (t.u * (float) color_width);
        int iy = (int) (t.v * (float) color_height);
            if (ix >= 0 && ix < color_width ) {
                if ( iy >= 0 && iy < color_height ) {
                    unsigned short r = vf_data_us[iy * color_width + ix + 0];
                    unsigned short g = vf_data_us[iy * color_width + ix + 1];
                    unsigned short b = vf_data_us[iy * color_width + ix + 2];

But it does not seem to work...

[obypix]

I forgot to add the main loop, where the texture coordinate comes from:

for (int i = 0; i < points.size(); i++)
{
    if (vertices[i].z)
    {
        rs2::vertex v = vertices[i];
        rs2::texture_coordinate t = tex_coords[i];

        int ix = (int) (t.u * (float) color_width);
        int iy = (int) (t.v * (float) color_height);

            if (ix >= 0 && ix < color_width ) {
                if ( iy >= 0 && iy < color_height ) {
                    unsigned short r = vf_data_us[iy * color_width + ix + 0];
                    unsigned short g = vf_data_us[iy * color_width + ix + 1];
                    unsigned short b = vf_data_us[iy * color_width + ix + 2];

[obypix]

oops, instead of unsigned short which is 16 bits, I should use unsigned char or uint8_t
but I am not sure I have the t.u and t.v order right? I am getting a garbled image mapping still

[obypix]

and another oops, I forgot to multiply the ix and iy offsets by 3
so this works and gets the right color values:

                    uint8_t r = vf_data_us[iy * color_width * 3 + ix*3 + 0];
                    uint8_t g = vf_data_us[iy * color_width * 3 + ix*3 + 1];
                    uint8_t b = vf_data_us[iy * color_width * 3 + ix*3 + 2];