xpic would seem to be the appropriate solution here because he’s looking for something that would appear to place a user selected chess piece at a particular position on a persistent image of a chess board. “xpic” allows for overlaying the image of a specific chess piece onto the static chess board without this overlay being persistent (no redrawing the chess board required to remove or change the chess piece overlay, simply refresh ‘ref’ to clear the xpic drawn piece)
To use pageX.pic= would basically require redrawing the underlying chess board image on every update.
I suppose you could make individual images of each chess piece+color all with the same dimensions and place a picture object at that point on the page then use p0.pic= to change the displayed piece and ‘vis’ to hide/show the piece at the pre-determined screen coordinates. Picture images can’t be moved or repositioned thought (except on Intelligent series) while ‘xpic’ would allow for positioning any chess piece image at any board/screen position on the fly (basically moving or repositioning pieces at runtime like an actual chess game). 'xpic" would also allow for more flexibility in chess piece image sizes by allowing for a single picture that contains every chess piece display variant and each individual piece to be essentially “clipped” from this master image and copied onto the chess board (no restrictions on individual piece dimensions either).
Xpic really does seem to be the ideal solution here.
For realistic placement of individual pieces I might even include scaled versions of each individual piece in the master image to allow for 3D depth on the chess board. You basically scan through the currently placed board pieces from deepest depth and move back one row at a time with the images of pieces nearest to the viewer appearing larger and correctly obscuring any board pieces positioned deeper on the board. To clear or move a previously placed piece simply use ‘xpic’ and clip the only the necessary square from the chess board image and place it over the position needing to appear cleared.