I found the answer to my own question.
There is a demo program called SAPHTML_R3HTTP_DEMO.
It uses Screen Painter and Menu painter so you have to remember to take care of those.
The bread and butter is the following:
*(Build your address here.)
CONCATENATE html_control->m_http_htmlviewer (build your address here.)
‘wwwdata/SAPHTML_R3HTTP_DEMO’ INTO doc_url. “#EC NOTEXT
CALL METHOD html_control->show_url
url = doc_url.
ENDFORM. ” LOAD_HOME_PAGE
I copied SAPHTML_R3HTTP_DEMO as an INCLUDE in another program and called it
with call screen 100.