Gamma/Photon : Using Gamma™ with the Photon microGUI®, Version 1.1
	Widget Classes

`PtMeter`

PtMeter — An arc-shaped real-time meter with indicator needle (in QNX 6).

Synopsis

class PtMeter PtBasic
{
    meter_color;                  // color  (Pt_ARG_METER_COLOR)    
    meter_flags;                  // flag  (Pt_ARG_METER_FLAGS)    
    meter_font_color;             // color  (Pt_ARG_METER_FONT_COLOR)    
    meter_increment;              // integer  (Pt_ARG_METER_INCREMENT)    
    meter_key_left;               // integer  (Pt_ARG_METER_KEY_LEFT)    
    meter_key_right;              // integer  (Pt_ARG_METER_KEY_RIGHT)    
    meter_level1_color;           // color  (Pt_ARG_METER_LEVEL1_COLOR)    
    meter_level1_pos;             // short  (Pt_ARG_METER_LEVEL1_POS)    
    meter_level2_color;           // color  (Pt_ARG_METER_LEVEL2_COLOR)    
    meter_level2_pos;             // short  (Pt_ARG_METER_LEVEL2_POS)    
    meter_level3_color;           // color  (Pt_ARG_METER_LEVEL3_COLOR)    
    meter_max_needle_position;    // short  (Pt_ARG_METER_MAX_NEEDLE_POSITION)    
    meter_min_needle_position;    // short  (Pt_ARG_METER_MIN_NEEDLE_POSITION)    
    meter_needle_color;           // color  (Pt_ARG_METER_NEEDLE_COLOR)    
    meter_needle_position;        // short  (Pt_ARG_METER_NEEDLE_POSITION)    
    meter_num_severity_levels;    // short  (Pt_ARG_METER_NUM_SEVERITY_LEVELS)    
    meter_text_font;              // string  (Pt_ARG_METER_TEXT_FONT)    
}

Base Classes

PtWidget <-- PtBasic <-- PtMeter

Description

This widget is a half-circle meter with an indicator needle and up to three different-colored pie-shaped arcs that mark three chosen ranges on the meter. The QNX 4 version of this widget is RtMeter.

For detailed information, please refer to PtMeter in the Photon documentation.

Instance Variables

meter_color

A number specifying the color used for the meter's center, outline, and tick marks. Default is 0x0 (black).

meter_flags

This instance variable controls characteristics of the widget, and may have one or two of the following values:

Constant	Description
`PtM_NON_SELECTABLE`	The meter is non-interactive.
`PtM_SELECTABLE`	The meter is interactive. Default is ON.
`PtM_NO_TEXT`	The minimum and maximum values are not displayed.

meter_font_color

A number specifying the color for the display of minimum and maximum values. Default is 0x0 (black).

meter_increment

A number of units to move the needle when an assigned key is pressed.

meter_key_left , meter_key_right

A number or key name from PkKeyDef.lsp for the key that moves the needle to the left or right. Defaults are Pk_Left and Pk_Right. You can load the key name constants with a call to require_lisp("PkKeyDef.lsp").

meter_level1_color

A number specifying a color for the left arc of the meter that corresponds to Level 1. Default is 0x00ff00 (green).

meter_level1_pos

A number specifying the end of Level 1, expressed as a percentage of the whole meter. Default is 50. This setting is unaffected by changes to meter_max_needle_position or meter_min_needle_position.

meter_level2_color

A number specifying a color for the center arc of the meter that corresponds to Level 2. Default is 0xffff00 (yellow).

meter_level2_pos

A number specifying the end of Level 2, expressed as a percentage of the whole meter. Default is 75. This setting is unaffected by changes to meter_max_needle_position or meter_min_needle_position.

meter_level3_color

A number specifying a color for the right arc of the meter that corresponds to Level 3. Default is 0xff0000 (red).

meter_max_needle_position

A number specifying the maximum point on the meter, the maximum value for the needle to register.

meter_min_needle_position

A number specifying the minimum point on the meter, the minimum value for the needle to register.

meter_needle_color

A number specifying the color of the needle. Default is 0xffffff (white).

meter_needle_position

A number specifying the current position of the needle, within the range of meter_min_needle_position and meter_max_needle_position. The needle will remain at the maximum or minimum position for any value outside that range.

meter_num_severity_levels

The number of arcs that the meter is divided into. The maximum number is 3, which is also the default.

meter_text_font

A string specifying the font used for displaying the maximum and minimum values. Default is "helv10".

Associated Classes

PtMeterCallback, PtCallbackInfo

Example

This example, ex_Meter.g, is included in the product distribution.

#!/usr/cogent/bin/phgamma

/*
 * This example demonstrates an RtMeter in QNX 4, or a
 * PtMeter in QNX 6.
 */

require_lisp("PhotonWidgets.lsp");
PtInit(nil);

function display_value(wnum, wmet)
{
  wmet.meter_needle_position = wnum.numeric_value;
}

function reset_num(wnum, wmet)
{
  wnum.numeric_value = wmet.meter_needle_position;
}

win = new(PtWindow);
win.SetArea(100, 100, 250, 250);
if (_os_ == "QNX4")
     meter = new(RtMeter);
else if (_os_ == "QNX6")
     meter = new(PtMeter);

meter.SetArea(20, 40, 200, 200);
meter.meter_color = 0xccddff;
meter.meter_max_needle_position = 150;
meter.meter_min_needle_position = 0;
meter.meter_level1_color = 0x00ff00;
meter.meter_level1_pos = 50;
meter.meter_level2_color = 0xffff00;
meter.meter_level2_pos = 100;
meter.meter_level3_color = 0xff0000;
meter.meter_needle_position = 70;
meter.meter_needle_color = 0x000000;

num = new(PtNumericInteger);
num.SetArea(100, 150, 50, 20);
num.numeric_increment = 10;
num.numeric_min = 0;
num.numeric_max = 150;
num.numeric_value = 70;
num.numeric_flags = cons(Pt_NUMERIC_WRAP, nil);
num.numeric_flags = cons(Pt_NUMERIC_AUTO_HIGHLIGHT, nil);

label = new(PtLabel);
label.SetPos(10, 190);
label.text_font = "helv09";
label.text_string = string("Adjust the meter by clicking anywhere,\n",
			   "by dragging the needle, or by changing \n",
			   "the value in the PtNumeric widget.");

if (_os_ == "QNX4")
     PtAttachCallback(meter, Rt_CB_METER_MOVED, `reset_num(@num, @meter));
else if (_os_ == "QNX6")
     PtAttachCallback(meter, Pt_CB_METER_MOVED, `reset_num(@num, @meter));
     
PtAttachCallback(num, Pt_CB_NUMERIC_CHANGED, `display_value(@num, @meter));
display_value(num, meter);

PtRealizeWidget(win);
PtMainLoop();


PtMessage		PtMultiText