2 GP Reference Entries

with-transformed-points

Macro

Summary

Binds a list of transformed points in a port to a list across the execution of the macro's body.

Signature

with-transformed-points (points port) &body body => result

Arguments

points: A list of real numbers
port: A graphics port

Values

result: The return value of the last form executed in body

Description

Thewith-transformed-points macro binds points to a new list of x and y values obtained by post-multiplying them by the current transform of port, and then evaluates body. The points symbol must be bound to a list of alternating x and y values representing coordinate points in the port.