Piyadasa was born in 1939 in Kuantan, the capital of Pahang, in a family of Sinhalese origin.
Consequently, he returned to Malaysia, where he started to work as a teacher at the School for Art and Design, which shortly before was founded as a part of the Universiti Teknologi MARA.
By means of his publications in Malaysian as well as in English, he importantly filled up a vacuum of the sixties and seventies.
He initiated a hardly existing debate in this time in his country on art critic and history.
His critiques offered an answer on the neo-nationalist, Islamic and global currents in Malaysia.