1PLCALC_WORLD(3plplot) PLplot API PLCALC_WORLD(3plplot)
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6 plcalc_world - Calculate world coordinates and corresponding window in‐
7 dex from relative device coordinates
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10 plcalc_world(rx, ry, wx, wy, window)
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13 Calculate world coordinates, wx and wy, and corresponding window index
14 from relative device coordinates, rx and ry.
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16 Redacted form: General: plcalc_world(rx, ry, wx, wy, window)
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19 This function is used in example 31.
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22 rx (PLFLT(3plplot), input)
23 Input relative device coordinate (0.0-1.0) for the x coordinate.
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25 ry (PLFLT(3plplot), input)
26 Input relative device coordinate (0.0-1.0) for the y coordinate.
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28 wx (PLFLT_NC_SCALAR(3plplot), output)
29 Returned value of the x world coordinate corresponding to the
30 relative device coordinates rx and ry.
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32 wy (PLFLT_NC_SCALAR(3plplot), output)
33 Returned value of the y world coordinate corresponding to the
34 relative device coordinates rx and ry.
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36 window (PLINT_NC_SCALAR(3plplot), output)
37 Returned value of the last defined window index that corresponds
38 to the input relative device coordinates (and the returned world
39 coordinates). To give some background on the window index, for
40 each page the initial window index is set to zero, and each time
41 plwind(3plplot) is called within the page, world and device co‐
42 ordinates are stored for the window and the window index is in‐
43 cremented. Thus, for a simple page layout with non-overlapping
44 viewports and one window per viewport, window corresponds to the
45 viewport index (in the order which the viewport/windows were
46 created) of the only viewport/window corresponding to rx and ry.
47 However, for more complicated layouts with potentially overlap‐
48 ping viewports and possibly more than one window (set of world
49 coordinates) per viewport, window and the corresponding output
50 world coordinates corresponds to the last window created that
51 fulfills the criterion that the relative device coordinates are
52 inside it. Finally, in all cases where the input relative de‐
53 vice coordinates are not inside any viewport/window, then the
54 returned value of the last defined window index is set to -1.
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58 Many developers (who are credited at http://plplot.org/credits.php)
59 have contributed to PLplot over its long history.
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62 PLplot documentation at http://plplot.org/documentation.php.
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66 July, 2022 PLCALC_WORLD(3plplot)