The Slider

[powersoft]

I have programmed a slider, see code below.
The slider is not working well.
I run this code on Uno.
Wat is wrong on this?


Thanks


#==================================================
#include <SPI.h>
#include <GD2.h>


#define TAG_SLIDER 201

int waarde=180;

void setup() {
Serial.begin(115200);
GD.begin();
}

void loop() {
  GD.ClearColorRGB(0x103000);
  GD.Clear();

  //Draw clock
  GD.cmd_clock(50,50,50,OPT_FLAT,12,33,45,0);

  //Draw Slider
  GD.Tag(TAG_SLIDER);
  GD.cmd_slider(100,150,100,10,OPT_FLAT,waarde,360);
  GD.cmd_track( 100,150,100,10,TAG_SLIDER);

  GD.get_inputs(); 
  switch (GD.inputs.track_tag & 0xff) {
  case TAG_SLIDER:
  {
    waarde=GD.inputs.track_val;
    Serial.println(waarde);
    break;
  }
 }
GD.swap();
}

[jamesbowman]

Aha, OK. So the problem here is that there is a difference between the range of the slider 0-360:

GD.cmd_slider(100,150,100,10,OPT_FLAT,waarde,360);
and the range of the tracker, because GD.inputs.track_val is always 0-65535:

GD.cmd_track(100,150,100,10,TAG_SLIDER);
...
waarde = GD.inputs.track_val;

So the fix is to either (1) make the slider (and waarde) have a range of 0-65535:

GD.cmd_slider(100,150,100,10,OPT_FLAT,waarde,65535);
or (2) rescale the result from track_val to the range 0-360:

waarde = GD.inputs.track_val * 360L / 65535;
Here is the whole program for option (2):


#include <SPI.h>
#include <GD2.h>


#define TAG_SLIDER 201

int waarde=180;

void setup() {
 Serial.begin(115200);
 GD.begin();
}

void loop() {
 GD.ClearColorRGB(0x103000);
 GD.Clear();

 //Draw clock
 GD.cmd_clock(50,50,50,OPT_FLAT,12,33,45,0);

 //Draw Slider
 GD.Tag(TAG_SLIDER);
 GD.cmd_slider(100,150,100,10,OPT_FLAT,waarde,360);
 GD.cmd_track( 100,150,100,10,TAG_SLIDER);

 GD.get_inputs();
 switch (GD.inputs.track_tag & 0xff) {
 case TAG_SLIDER:
   waarde = GD.inputs.track_val * 360L / 65535;
   Serial.println(waarde);
   break;
  }
 GD.swap();
}