DPFRST(3NCARG)

💖 DPFRST — bestie, let's start a curve 💖

okay so this is a page from the NCAR GRAPHICS manual, section 3NCARG, and the star of the show is DPFRST. no cap, it's lowkey one of the most important little subroutines in the Dashpack fam. sit down, hydrate, and let's get into it 🫶

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✨ NAME ✨

DPFRST — specifies the first point in a sequence of points, in the user coordinate system, defining a curve to be drawn. it's giving "everyone, meet the starting point of our curve" 💅

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✨ SYNOPSIS ✨

CALL DPFRST (XCPU,YCPU)

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✨ C-BINDING SYNOPSIS ✨

#include <ncarg/ncargC.h>

void c_dpfrst (float xcpu, float ycpu);

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✨ DESCRIPTION ✨

• XCPU — an input expression of type REAL that specifies the X coordinate of a point, in the user coordinate system. it's the horizontal vibe 🦋
• YCPU — an input expression of type REAL that specifies the Y coordinate of a point, in the user coordinate system. and that's the vertical vibe 🌸

💜 C-BINDING DESCRIPTION 💜

the C-binding argument descriptions are literally the same as the FORTRAN argument descriptions. no notes, same energy, periodt ✨

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✨ USAGE ✨

so here's the tea, bestie 🍓: you call DPFRST to do a "pen-up" move to the first of a sequence of points defining a curve. like, the pen is in the air, we're just traveling to the spot, no ink yet.

then you call DPVECT to do the "pen-down" moves to each of the other points in the sequence — now we're actually drawing, bestie, ink is flowing 💅

and then you call DPLAST to finish drawing the curve and flush the buffers. chef's kiss, the curve is done, the buffers are squeaky clean 👑

behind the scenes (and this part is important, don't skip it): DPFRST maps the input coordinates to the fractional coordinate system and then does a "pen-up" call to either DPDRAW (if smoothing is turned off) or to DPSMTH (if smoothing is turned on) with those coordinates. so it's basically the bouncer at the door deciding which function gets the point 🚪✨

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✨ EXAMPLES ✨

use the ncargex command to see the following relevant examples: tdshpk. go look, it's right there, it's iconic 🔥

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✨ ACCESS ✨

to use DPFRST or c_dpfrst, load the NCAR Graphics libraries ncarg, ncarg_gks, and ncarg_c — preferably in that order. don't switch up the order, bestie, it's not a vibe 🙈

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✨ SEE ALSO ✨

Online: dashpack, dashpack_params, dpcurv, dpdraw, dpgetc, dpgeti, dpgetr, dplast, dpline, dpsetc, dpseti, dpsetr, dpsmth, dpvect, ncarg_cbind.

Hardcopy: None.

(ngl the online list is stacked, that's the whole friend group fr fr 🫶)

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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.

⚠️ real talk: the use of this Software is governed by a License Agreement. so read it, bestie, it's not optional 💀

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and that's the whole page!! 🌈 this one shipped with the UNIX manual, dated March 1995, from your friends at NCAR GRAPHICS. stay slay, go draw some gorgeous curves, and remember: pen up, pen down, DPLAST, done. 💖✨🎀🦋