I don't use a product called "structure mapping", that is a Lowrance thingy, but I do use two programs that create HD contour mapping.
One is included with Humminbird ONIX units and the new Humminbird Helix 9, 10, and 12 series called Auto Charts Live. It does the contour mapping in real time on the unit.
That same software is available for computers as the Auto Chart or Auto Chart Pro program. That takes sonar logs done with Humminbird units and converts them to contour mapping on the computer and copied to a memory card for that purpose to be read by Humminbird units as Lakemaster mapping.
The other is Navionics Sonar Charts. That takes sonar logs and converts them to HD contour mapping by uploading the logs to the Navionics server where they are processed to be download as the Sonar Charts map layer and is shared on the Web App, Mobile App, and by anyone updating their Navionics card that has the Sonar Charts capability.
A version of that is Navionics Sonar Charts Live that does real time contour mapping via WiFi to a smartphone or tablet Navionics Mobile App. That can be private or shared. When shared, the created contour map is automatically uploaded to the Navionics Sonar Charts server to be handled the same as the above.
The data supplied via WiFi can be from a Vexilar Sonarphone, Lowrance WiFi, Raymarine WiFish and another company's equipment--forgot.
I have done over 200 sonar logs for the Navionics Sonar Charts program. Some created a HD contour map where none existed of any type--paper or digital and not even an outline of the shore.
Some created better detail than available maps that are not HD.
Humminbird Helix 12 CHIRP SI, 1198c SI, 1198c SI, ONIX 10 SI NT, Helix 7 CHIRP SI GPS G2, SOLIX 12 SI, 360, RC-1