C-Hook Callback Function Usage

[MCHulk]

I've compiled the example 1 of chapter24 "CBACKS" with the ch_repaint_function():

code:

---

extern boolean CH_ENTRY ch_repaint_on=FALSE;

extern void CH_ENTRY ch_repaint_function(void)

{

p_3d pointToDraw;

pointToDraw[0]=pointToDraw[1]=pointToDraw[2]= 0.0;

draw_3d_point(pointToDraw, YELLOW);

}

---

It compiled without errors, but it didn't work.

I think MC doesn't recognize the ch_repaint_function as the callback-function.

What's wrong?

Please help.

 

Thanks in advance,

MCHulk

 

[ 12-26-2002, 07:39 AM: Message edited by: MCHulk ]

[bryan314]

MCHulk,

 

try setting

extern boolean CH_ENTRY ch_repaint_on=FALSE;

to

extern boolean CH_ENTRY ch_repaint_on=TRUE;

 

I think the FALSE maybe a typo.

 

Or it's iniatialized in the off position, so to speak, and you turn in on (TRUE) OR off (FALSE) in your program as needed.

 

I hope that works.

 

Bryan

[MCHulk]

Bryan314,

 

thanks for your answer.

I tried both variants. It didn't work.

 

Any other idea?

 

MCHulk

 

[ 12-26-2002, 11:38 AM: Message edited by: MCHulk ]

[bryan314]

MCHulk,

 

Yep have one more;

 

The chook is probably exiting before the call back can be called. Say that ten times fast.

 

The following is modification of the dummy yourfile.c in the sdk. I added the include for m_gragh.h for the draw_3d_point but you probably alread have that. Added the callback with the TRUE. The clear text and wait for functions are only there to keep the chook 'active'. Compile, run, and repaint. You should now see a yellow point in the center of the screen. Hitting enter or clicking the screen will return the waitforspace function and exit the chook. Repaint again and the dot disapears.

 

Bryan

 

code:

---

 /* yourfile.c */

 

#include <stdlib.h>

#include <stdio.h>

#include "m_vars.h"

#include "m_ncvars.h"

#include "m_menu.h"

#include "m_io.h"

#include "m_dbm.h"

#include "m_init.h"

 

#include "m_graph.h" // C-Hook header: graphics functions

 

 

extern boolean CH_ENTRY ch_repaint_on=TRUE;

extern void CH_ENTRY ch_repaint_function(void)

{

p_3d pointToDraw;

pointToDraw[0]=pointToDraw[1]=pointToDraw[2]= 0.0;

draw_3d_point(pointToDraw, YELLOW);

}

 

/* replace this with your function */

void your_function(void)

{

cleartextall();

wait_for_space();

 

 

}/* end your function */

 

 

 

 

 

/************************************************/

/* do not delete m_main() */

/* M_MAIN FUNCTION */

/************************************************/

void CH_ENTRY m_main (long *ptrs)

{

if (open_app (ptrs))

if (product_level_1_or_design_enabled())

{

/* put your function here */

 

your_function();

}

close_app (ptrs);

}

/************************************************/

/* do not delete m_main() */

/* END M_MAIN FUNCTION */

/************************************************/

---

[MCHulk]

Bryan314,

 

thank you very much.

It works fine.

 

Thanks,

MCHulk

[bryan314]

MCHulk,

 

You're welcome.

Glad I could help.

 

Bryan

 

[ 12-27-2002, 07:58 AM: Message edited by: bryan314 ]