I'm trying to write a program in which a knob drawn in an OpenGL window functions as a GUI widget. Here's the class for the knob:
There are more functions and members, but this is the important bit.
double value, max, min, default, step, scrollStep;
void setTarget (void*);
// Function to set the target
void gluisKnob::setTarget (void * TARGET)
target = TARGET;
The knob is to turn when clicked and dragged, or when scrolled on, and changes the value of a variable that target points to.
I have no trouble assigning the address of some other variable (int, float, whatever) to target but how do I use that to assign a value to the variable it points to?
// This part is during the program's main loop
if (user_clicks_and_drags_the_knob() )
knob.target = knob's_new_value; // This doesn't work
*knob.target = knob's_new_value; // This gives the error message in the thread title
knob.*target = knob's_new_value // This doesn't work either.