Scale.txt revision 9aa228fd 
1
2Scale Widget
3
4Header file 		Scale.h
5Class			scaleWidgetClass
6Class Name		Scale
7Superclass		Simple
8
9The Scale widget is an immutable image displayed within a rectangular
10region of the screen.  When the widget is selected, it is highlighted, 
11and an application callback routine is invoked.  When the
12widget is resized the image can be autoscaled to fit new size of the 
13widget window.  The widget can also cut and paste its contents.
14
15When creating a Scale widget instance, the following resources are
16retreived from the argument list or from the resource database:
17
18All the Simple Widget resources plus...
19-------------------------------------------------------------------------------
20 Name                Cass               Type            Default Value
21-------------------------------------------------------------------------------
22 aspectRatio         AspectRatio        Float           1.0
23 autoscale           Autoscale          Boolean         True
24 bufferSize          BufferSize         Cardinal        1024
25 foreground          Foreground         Pixel           XtDefaultForeground
26 gravity             Gravity            XtGravity       ForgetGravity
27 image               Image              XImage*         NULL
28 internalHeight      Height             Dimension       2
29 internalWidth       Width              Dimension       2
30 pasteBuffer         PasteBuffer        Boolean         False
31 precision           Precision          Float           0.001
32 proportional        Proportional       Boolean         True
33 resize              Resize             Boolean         True
34 scaleX              ScaleFactor        Float           DefaultScaleValue
35 scaleY              ScaleFactor        Float           DefaultScaleValue
36 exponent            Exponent           integer         -3
37-------------------------------------------------------------------------------
38
39 aspectRatio	This resource specifies the aspect ratio of the scaled image
40		in the x / y * aspectRatio = 1 form.  It is effective within
41		the precision resource only if proportional resource is set 
42		to true.  AspectRatio resource can be any positive number 
43		greater than zero.
44
45 autoscale	If this resource is set to True then the image will be
46		autoscaled to fit the window size within internal width
47		and internal height resource values.  If the resource is
48		False, the widget will only reposition the image
49		according to the gravity resource value.
50
51 bufferSize	This resource specifies the buffer size in XRectangle's for
52		buffering the XFillRectangle calls.  It is effective only 
53		for XYBitmap image type.
54
55 background	This resource has the same meaning as for the Simple widget.
56		However, it is worth mentioning that if the most frequent
57		pixel value in the XYPixmap or ZPixmap image is specified
58		as backgroud, the scaling process can be speeded up noticably.
59
60 foreground	The color used to paint the image if in XYBitmap format.
61		If the image is XYPixmap or ZPixmap format, the foreground
62		resource has no effect.
63
64 gravity	This resource will determine where to put the image if it does 
65		not fit the window size minus internal width and height.
66		The widget will try to preserve gravity rather than internal
67		width and height resources.
68
69 image		This is the image to be displayed in the widget window.
70		If no image is desired, the NULL value can be passed.  
71		The passed image is copied and set to the resource value.
72		Applications should destroy the passed image argument
73		if they do not intend to use it at some later time.
74
75 internalHeight	
76 internalWidth	These resources specify the minimum distance from the boarder 
77		of the widget window to be maintanied when manipulating the 
78		image.  If image is too big or small to satisfy given 
79		conditions, the	widget will position the image to preserve 
80		gravity rather than internalWidth or internalHeight.
81
82 pasteBuffer	If this resource is true then the widget owns the paste
83		selection buffer.  This resource can only be queried.
84
85 precision	This resource specifies the precision of the scale factors
86		when scaling the image.  The precision resource can be any 
87		positive number greater than zero. (For example, if precision
88		is 1.0 then the image will be scaled only by integer values.)
89
90 proportional	If this resource is set to true it will make sure that the 
91                image proportions, as specified by aspectRatio resource,
92                are being kept whenever it is scaled.  
93		
94 resize		If this resource is true the widget will try to resize when
95		addopting a new image thus preserveing the scale values.
96		If it is false the scale values will not be preserved unless
97		the image can fit in the current window size with the same
98		scale values.
99
100 scaleX
101 scaleY		These resources specify the scaling values for the widget
102		image.  They will be floored to satisfy precision resource
103		values.  If uniform resource is true the scale values will
104		be only integers.  These resources can be any positive number
105		greater than zero.
106
107 shiftFactor	...
108