# wx.lib.agw.speedmeter¶

SpeedMeter tries to reproduce the behavior of some car controls (but not only), by creating an “angular” control (actually, circular).

## Description¶

SpeedMeter tries to reproduce the behavior of some car controls (but not only), by creating an “angular” control (actually, circular). I remember to have seen it somewhere, and i decided to implement it in wxPython.

SpeedMeter starts its construction from an empty bitmap, and it uses some functions of the wx.DC class to create the rounded effects. everything is processed in the Draw() method of SpeedMeter class.

This implementation allows you to use either directly the PaintDC, or the better (for me) double buffered style with BufferedPaintDC. the double buffered implementation has been adapted from the wxPython wiki example:

http://wiki.wxpython.org/index.cgi/doublebuffereddrawing

## Usage¶

Usage example:

import wx
import wx.lib.agw.speedmeter as SM

class MyFrame(wx.Frame):

def __init__(self, parent):

wx.Frame.__init__(self, parent, -1, "SpeedMeter Demo")

speed = SM.SpeedMeter(self, agwStyle=SM.SM_DRAW_HAND|SM.SM_DRAW_SECTORS|SM.SM_DRAW_MIDDLE_TEXT|SM.SM_DRAW_SECONDARY_TICKS)

# Set The Region Of Existence Of SpeedMeter (Always In Radians!!!!)
speed.SetAngleRange(-pi/6, 7*pi/6)

# Create The Intervals That Will Divide Our SpeedMeter In Sectors
intervals = range(0, 201, 20)
speed.SetIntervals(intervals)

# Assign The Same Colours To All Sectors (We Simulate A Car Control For Speed)
# Usually This Is Black
colours = [wx.BLACK]*10
speed.SetIntervalColours(colours)

# Assign The Ticks: Here They Are Simply The String Equivalent Of The Intervals
ticks = [str(interval) for interval in intervals]
speed.SetTicks(ticks)
# Set The Ticks/Tick Markers Colour
speed.SetTicksColour(wx.WHITE)
# We Want To Draw 5 Secondary Ticks Between The Principal Ticks
speed.SetNumberOfSecondaryTicks(5)

# Set The Font For The Ticks Markers
speed.SetTicksFont(wx.Font(7, wx.FONTFAMILY_SWISS, wx.FONTSTYLE_NORMAL, wx.FONTWEIGHT_NORMAL))

# Set The Text In The Center Of SpeedMeter
speed.SetMiddleText("Km/h")
# Assign The Colour To The Center Text
speed.SetMiddleTextColour(wx.WHITE)
# Assign A Font To The Center Text
speed.SetMiddleTextFont(wx.Font(8, wx.FONTFAMILY_SWISS, wx.FONTSTYLE_NORMAL, wx.FONTWEIGHT_BOLD))

# Set The Colour For The Hand Indicator
speed.SetHandColour(wx.Colour(255, 50, 0))

# Do Not Draw The External (Container) Arc. Drawing The External Arc May
# Sometimes Create Uglier Controls. Try To Comment This Line And See It
# For Yourself!
speed.DrawExternalArc(False)

# Set The Current Value For The SpeedMeter
speed.SetSpeedValue(44)

# our normal wxApp-derived class, as usual

app = wx.App(0)

frame = MyFrame(None)
app.SetTopWindow(frame)
frame.Show()

app.MainLoop()


## Methods and Settings¶

SpeedMeter is highly customizable, and in particular you can set:

• The start and end angle of existence for SpeedMeter;

• The intervals in which you divide the SpeedMeter (numerical values);

• The corresponding thicks for the intervals;

• The interval colours (different intervals may have different filling colours);

• The ticks font and colour;

• The background colour (outsize the SpeedMeter region);

• The external arc colour;

• The hand (arrow) colour;

• The hand’s shadow colour;

• The hand’s style (“arrow” or “hand”);

• The partial filler colour;

• The number of secondary (intermediate) ticks;

• The direction of increasing speed (“advance” or “reverse”);

• The text to be drawn in the middle and its font;

• The icon to be drawn in the middle;

• The first and second gradient colours (that fills the SpeedMeter control);

• The current value.

## Window Styles¶

This class supports the following window styles:

Window Styles

Hex Value

Description

SM_ROTATE_TEXT

0x1

Draws the ticks rotated: the ticks are rotated accordingly to the tick marks positions.

SM_DRAW_SECTORS

0x2

Different intervals are painted in differend colours (every sector of the circle has its own colour).

SM_DRAW_PARTIAL_SECTORS

0x4

Every interval has its own colour, but only a circle corona is painted near the ticks.

SM_DRAW_HAND

0x8

The hand (arrow indicator) is drawn.

SM_DRAW_SHADOW

0x10

A shadow for the hand is drawn.

SM_DRAW_PARTIAL_FILLER

0x20

A circle corona that follows the hand position is drawn near the ticks.

SM_DRAW_SECONDARY_TICKS

0x40

Intermediate (smaller) ticks are drawn between principal ticks.

SM_DRAW_MIDDLE_TEXT

0x80

Some text is printed in the middle of the control near the center.

SM_DRAW_MIDDLE_ICON

0x100

An icon is drawn in the middle of the control near the center.

SM_DRAW_GRADIENT

0x200

A gradient of colours will fill the control.

SM_DRAW_FANCY_TICKS

0x400

With this style you can use xml tags to create some custom text and draw it at the ticks position. See lib.fancytext for the tags.

## Events Processing¶

No custom events are available for this class.

## License And Version¶

SpeedMeter is distributed under the wxPython license.

Latest revision: Andrea Gavana @ 27 Dec 2012, 21.00 GMT

Version 0.3

## Classes Summary¶

 BufferedWindow A buffered window class. SpeedMeter SpeedMeter tries to reproduce the behavior of some car controls (but not only),