Positions

Building Positions

(position-new col row): MediaScheme Position Procedure. Build a new position that represents the point at (col,row).

Accessing Components

(position-col pos): MediaScheme Position Procedure. Extract the column from position pos.
(position-row pos): MediaScheme Position Procedure. Extract the row from position pos.

Miscellaneous

(position? value): MediaScheme Position Procedure. Determine if value is a position (or can be interpreted as such).
(position-offset position hoff voff): MediaScheme Position Procedure. Create a new position, offset from position horizontally by hoff and vertically by voff.
(position-distance pos1 pos2): MediaScheme Position Procedure. Compute the distance between pos1 and pos2.
(position-interpolate pos1 pos2 percent): MediaScheme Position Procedure. Create a new position which is percent (expressed as a real number between 0 and 1) of the way from pos1 to pos2
(random-positions n cols rows): MediaScheme Position Procedure. Create n positions, each of which is difficult to predict and each with a non-negative column less than cols and a non-negative row less than rows.

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Samuel A. Rebelsky, rebelsky@grinnell.edu

This material is based upon work partially supported by the National Science Foundation under Grant No. CCLI-0633090. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

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