Function:cs2sdhcb
From S2PLOT
cs2sdhcb
Set the handle dragging callback.
Prototype
void cs2sdhcb(void *cbfn);
Description
Set the drag handle callback function; use NULL argument to cancel callback.
The callback function must be of the form:
void dragfn(int *id, XYZ *pos)
where id is the identifier of the chosen handle and pos is a pointer to XYZ variable containing new coordinates.
A handle is dragged by pressing and holding the SHIFT key, while pressing and holding the RIGHT MOUSE BUTTON.
See Also
| ds2ah | Add a handle to allow interactive picking of objects. |
| cs2scb | Set the callback function. |
| struct_XYZ | Data structure for (x,y,z) coordinates. |
Code Example
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include "s2plot.h"
#define N 10 /* Number of points */
XYZ xyz[N]; /* Global variable: positions */
COLOUR col[N]; /* Colour of the point */
int sel[N]; /* Global varibale: selected data */
void drag(int *id, XYZ *p) /* The drag callback */
{
xyz[*id] = *p; /* Update the dragged point's location */
}
void cb(double *t, int *kc)
{
COLOUR hilite = { 1.0, 1.0, 1.0 }; /* Highlight colour */
float hsize = 0.02; /* Size of handle */
int i; /* Loop variable */
for (i=0;i<N;i++) {
ns2vthpoint(xyz[i], col[i], 3); /* Draw thick point */
ds2ah(xyz[i], hsize, col[i], hilite, i, sel[i]); /* Draw handles */
}
}
int main(int argc, char *argv[])
{
int i; /* Loop varibale */
srand48((long)time(NULL)); /* Seed random numbers */
fprintf(stderr,"Shift and right mouse click to drag a handle\n");
s2opend("/?",argc, argv); /* Open the display */
s2swin(-1.,1., -1.,1., -1.,1.); /* Set the window coordinates */
s2box("BCDET",0,0,"BCDET",0,0,"BCDET",0,0); /* Draw coordinate box */
for (i=0;i<N;i++) { /* Set-up globals */
xyz[i].x = drand48()*2.0 - 1.0; /* Random position */
xyz[i].y = drand48()*2.0 - 1.0;
xyz[i].z = drand48()*2.0 - 1.0;
col[i].r = drand48(); /* Random colour */
col[i].g = drand48();
col[i].b = drand48();
sel[i] = 0; /* Not currently selected */
}
cs2scb(&cb); /* Install dynamic callback */
cs2sdhcb(&drag); /* Install handle dragging callback */
cs2thv(1); /* Make handles visible */
ss2txh(1); /* Make crosshairs visible */
s2show(1); /* Open the s2plot window */
return 1;
}
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