CPCHLL(3NCARG)

💖 CPCHLL — the Conpack label-drawing callback 💖

NCAR GRAPHICS bestie, gather round, because this one is a hook, not a function you call yourself. It's the little routine that Conpack pings every single time it draws a contour line label. The stock version? Does absolutely nothing. You're supposed to write your own if you want a say in what happens as those labels go down. 🎀

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✨ NAME ✨

CPCHLL — it gets called by the Conpack routines as contour line labels are drawn. The default version does nothing, like, literally nothing, it just sits there. A user-written version may be supplied to provide control as the labels are drawn. 👑

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🌸 SYNOPSIS 🌸

CALL CPCHLL (IFLG)

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🦋 DESCRIPTION 🦋

• IFLG (INTEGER, input) — positive if an action is about to be taken, negative if an action has just been completed. The action in question is defined by the absolute value of IFLG, and here's the whole menu, no skips:
  • The value 1 implies the determination of the size of the label (by means of a call to PLCHHQ, in the package Plotchar, with ANGD=360.).
  • The value 2 implies the filling of the box around the label, which is done before the drawing of the label itself.
  • The value 3 implies the drawing of the label (by means of a call to PLCHHQ, in the package Plotchar).
  • The value 4 implies the drawing of the box around the label, which is done after the drawing of the label itself.

Positive = "we're about to do the thing", negative = "okay we just finished the thing". Same number either way, sign tells you which side of the moment you're on. 🫶

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💅 USAGE 💅

Okay so real talk: CPCHLL is NOT to be called by the user. It gets called several times by CPLBAM and/or CPLBDR while each contour-line label is positioned and drawn. That's the whole point of it.

The default version of CPCHLL does nothing. A user-supplied replacement may change attributes such as color and line width (by calling the SPPS routine SETUSV or the appropriate GKS routines).

The text of the label may be retrieved by means of a:

CALL CPGETC ('CTM',CVAL)

The text of the label may be changed by means of a:

CALL CPSETC ('CTM',CVAL)

⚠️ This should only be done during a call with IFLG = 1 or 3 and, if it is done for one of those values, it should be done for the other. Do both or neither, bestie, that's the rule. 🙈

When CPCHLL is called, the parameter 'PAI' will have been set to the index of the appropriate contour level. Thus, parameters associated with that level may easily be retrieved by calls to CPGETx. 🌈

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⭐ ACCESS ⭐

To use CPCHLL, load the NCAR Graphics libraries ncarg, ncarg_gks, and ncarg_c — preferably in that order. Order matters, don't be chaotic. 🍓

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👑 SEE ALSO 👑

Online: conpack, cpback, cpchcf, cpchcl, cpchhl, cpchil, cpcica, cpclam, cpcldm, cpcldr, cpcltr, cpcnrc, cpdrpl, cpezct, cpgetc, cpgeti, cpgetr, cplbam, cplbdr, cpmpxy, cpmviw, cpmvrw, cppkcl, cppklb, cprect, cprset, cpscae, cpsetc, cpseti, cpsetr, cpsps1, cpsps2, ncarg_cbind

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💜 COPYRIGHT 💜

Copyright (C) 1987-2009 University Corporation for Atmospheric Research

The use of this Software is governed by a License Agreement.

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And that's the whole page, bestie — this one's from the UNIX manual, March 1993 era, filed under CPCHLL(3NCARG). Old-school but iconic, fr fr. Go write that replacement routine and slay. 💅✨