How can I change RGB values of pcl::PointXYZRGBA?

Question

I have a point of the type pcl::PointXYZRGBA. How can I assign/change its rgb values?

For changing xyz coordinates, I can simply do point.x = some_value.

Bacteriostat

The class Point does not seems to exist in the Pcl doc... I can only find pcl::PointXYZRGBA. – Chaudoin

@Chaudoin : You are right. I am referring to an instance named 'point' of the class pcl::PointXYZRGBA . – Bacteriostat

Can't you use getRGBEigen3i(), or point.r (and same for gand b) ? – Chaudoin

@Chaudoin : with getRGBEigen3i(), I cannot replace them. About using point.r, I found a thread on pcl-users forum that said otherwise. – Bacteriostat

i've replaced one of your tags, the correct one is point-cloud-library – Eisenstark

Answer 1

Or just use

point.r = 255;
point.b = 0;
point.g = 0;
point.a = 255;

Puggree

This should be the corrected answer. Simple and clear. – Billybillycock

Answer 2

You can use pcl::PointXYZRGB instead of pcl::PointXYZRGBA. I think they both do the same. And then to color a point red (255,0,0), you can do:

pcl::PointXYZRGB point = pcl::PointXYZRGB(255, 0, 0);

And the xyz-coordinates can then be assigned respectively:

point.x = x;
point.y = y;
point.z = z;

EDIT: Or if you have to stick with pcl::PointXYZRGBA, you can do

pcl::PointXYZRGBA point;
uint8_t r = 255;
uint8_t g = 0;
uint8_t b = 0;
int32_t rgb = (r << 16) | (g << 8) | b; 
point.rgba = *(float *)(&rgb); // makes the point red

Dysgenic

Your second part is wrong - .rgba is a uint32_t – Haughty