Question

Is is true that Pineda mapped through coast of Texas which helped other explorers know where to start their journeys

Answer 1

Yes it is True.
Alonso Alvarez de Pineda (1494-1520) - A Spanish traveler and map-maker, Pineda and his group were likely the first Europeans in Texas, asserting it for Spain. Little is known about Pineda's initial life, in any case, in 1517, he was cruising for the Spanish Governor of Jamaica, Francisco de Garay.