1 /*
2  * tkScale.h --
3  *
4  *	Declarations of types and functions used to implement the scale
5  *	widget.
6  *
7  * Copyright © 1996 Sun Microsystems, Inc.
8  * Copyright © 1999-2000 Scriptics Corporation.
9  *
10  * See the file "license.terms" for information on usage and redistribution of
11  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
12  */
13 
14 #ifndef _TKSCALE
15 #define _TKSCALE
16 
17 #ifndef _TKINT
18 #include "tkInt.h"
19 #endif
20 
21 /*
22  * Legal values for the "orient" field of TkScale records.
23  */
24 
25 enum orient {
26     ORIENT_HORIZONTAL, ORIENT_VERTICAL
27 };
28 
29 /*
30  * Legal values for the "state" field of TkScale records.
31  */
32 
33 enum state {
34     STATE_ACTIVE, STATE_DISABLED, STATE_NORMAL
35 };
36 
37 /*
38  * A data structure of the following type is kept for each scale widget
39  * managed by this file:
40  */
41 
42 typedef struct TkScale {
43     Tk_Window tkwin;		/* Window that embodies the scale. NULL means
44 				 * that the window has been destroyed but the
45 				 * data structures haven't yet been cleaned
46 				 * up.*/
47     Display *display;		/* Display containing widget. Used, among
48 				 * other things, so that resources can be
49 				 * freed even after tkwin has gone away. */
50     Tcl_Interp *interp;		/* Interpreter associated with scale. */
51     Tcl_Command widgetCmd;	/* Token for scale's widget command. */
52     Tk_OptionTable optionTable;	/* Table that defines configuration options
53 				 * available for this widget. */
54     enum orient orient;		/* Orientation for window (vertical or
55 				 * horizontal). */
56     int width;			/* Desired narrow dimension of scale, in
57 				 * pixels. */
58     int length;			/* Desired long dimension of scale, in
59 				 * pixels. */
60     double value;		/* Current value of scale. */
61     Tcl_Obj *varNamePtr;	/* Name of variable or NULL. If non-NULL,
62 				 * scale's value tracks the contents of this
63 				 * variable and vice versa. */
64     double fromValue;		/* Value corresponding to left or top of
65 				 * scale. */
66     double toValue;		/* Value corresponding to right or bottom of
67 				 * scale. */
68     double tickInterval;	/* Distance between tick marks; 0 means don't
69 				 * display any tick marks. */
70     double resolution;		/* If > 0, all values are rounded to an even
71 				 * multiple of this value. */
72     int digits;			/* Number of significant digits to print in
73 				 * values. 0 means we get to choose the number
74 				 * based on resolution and/or the range of the
75 				 * scale. */
76     char valueFormat[16];	/* Sprintf conversion specifier computed from
77 				 * digits and other information. */
78     char tickFormat[16];	/* Sprintf conversion specifier computed from
79 				 * tick interval. */
80     double bigIncrement;	/* Amount to use for large increments to scale
81 				 * value. (0 means we pick a value). */
82     char *command;		/* Command prefix to use when invoking Tcl
83 				 * commands because the scale value changed.
84 				 * NULL means don't invoke commands. */
85     int repeatDelay;		/* How long to wait before auto-repeating on
86 				 * scrolling actions (in ms). */
87     int repeatInterval;		/* Interval between autorepeats (in ms). */
88     char *label;		/* Label to display above or to right of
89 				 * scale; NULL means don't display a label. */
90     TkSizeT labelLength;	/* Number of non-NULL chars. in label. */
91     enum state state;		/* Values are active, normal, or disabled.
92 				 * Value of scale cannot be changed when
93 				 * disabled. */
94 
95     /*
96      * Information used when displaying widget:
97      */
98 
99     int borderWidth;		/* Width of 3-D border around window. */
100     Tk_3DBorder bgBorder;	/* Used for drawing slider and other
101 				 * background areas. */
102     Tk_3DBorder activeBorder;	/* For drawing the slider when active. */
103     int sliderRelief;		/* Is slider to be drawn raised, sunken,
104 				 * etc. */
105     XColor *troughColorPtr;	/* Color for drawing trough. */
106     GC troughGC;		/* For drawing trough. */
107     GC copyGC;			/* Used for copying from pixmap onto screen */
108     Tk_Font tkfont;		/* Information about text font, or NULL. */
109     XColor *textColorPtr;	/* Color for drawing text. */
110     GC textGC;			/* GC for drawing text in normal mode. */
111     int relief;			/* Indicates whether window as a whole is
112 				 * raised, sunken, or flat. */
113     int highlightWidth;		/* Width in pixels of highlight to draw around
114 				 * widget when it has the focus. <= 0 means
115 				 * don't draw a highlight. */
116     Tk_3DBorder highlightBorder;/* Value of -highlightbackground option:
117 				 * specifies background with which to draw 3-D
118 				 * default ring and focus highlight area when
119 				 * highlight is off. */
120     XColor *highlightColorPtr;	/* Color for drawing traversal highlight. */
121     int inset;			/* Total width of all borders, including
122 				 * traversal highlight and 3-D border.
123 				 * Indicates how much interior stuff must be
124 				 * offset from outside edges to leave room for
125 				 * borders. */
126     int sliderLength;		/* Length of slider, measured in pixels along
127 				 * long dimension of scale. */
128     int showValue;		/* Non-zero means to display the scale value
129 				 * below or to the left of the slider; zero
130 				 * means don't display the value. */
131 
132     /*
133      * Layout information for horizontal scales, assuming that window gets the
134      * size it requested:
135      */
136 
137     int horizLabelY;		/* Y-coord at which to draw label. */
138     int horizValueY;		/* Y-coord at which to draw value text. */
139     int horizTroughY;		/* Y-coord of top of slider trough. */
140     int horizTickY;		/* Y-coord at which to draw tick text. */
141     /*
142      * Layout information for vertical scales, assuming that window gets the
143      * size it requested:
144      */
145 
146     int vertTickRightX;		/* X-location of right side of tick-marks. */
147     int vertValueRightX;	/* X-location of right side of value string. */
148     int vertTroughX;		/* X-location of scale's slider trough. */
149     int vertLabelX;		/* X-location of origin of label. */
150 
151     /*
152      * Miscellaneous information:
153      */
154 
155     int fontHeight;		/* Height of scale font. */
156     Tk_Cursor cursor;		/* Current cursor for window, or NULL. */
157     Tcl_Obj *takeFocusPtr;	/* Value of -takefocus option; not used in the
158 				 * C code, but used by keyboard traversal
159 				 * scripts. May be NULL. */
160     int flags;			/* Various flags; see below for
161 				 * definitions. */
162 } TkScale;
163 
164 /*
165  * Flag bits for scales:
166  *
167  * REDRAW_SLIDER -		1 means slider (and numerical readout) need to
168  *				be redrawn.
169  * REDRAW_OTHER -		1 means other stuff besides slider and value
170  *				need to be redrawn.
171  * REDRAW_ALL -			1 means the entire widget needs to be redrawn.
172  * REDRAW_PENDING -		1 means any sort of redraw is pending
173  * ACTIVE -			1 means the widget is active (the mouse is in
174  *				its window).
175  * INVOKE_COMMAND -		1 means the scale's command needs to be
176  *				invoked during the next redisplay (the value
177  *				of the scale has changed since the last time
178  *				the command was invoked).
179  * SETTING_VAR -		1 means that the associated variable is being
180  *				set by us, so there's no need for ScaleVarProc
181  *				to do anything.
182  * NEVER_SET -			1 means that the scale's value has never been
183  *				set before (so must invoke -command and set
184  *				associated variable even if the value doesn't
185  *				appear to have changed).
186  * GOT_FOCUS -			1 means that the focus is currently in this
187  *				widget.
188  * SCALE_DELETED -		1 means the scale widget is being deleted
189  */
190 
191 #define REDRAW_SLIDER		(1<<0)
192 #define REDRAW_OTHER		(1<<1)
193 #define REDRAW_ALL		(REDRAW_OTHER|REDRAW_SLIDER)
194 #define REDRAW_PENDING		(1<<2)
195 #define ACTIVE			(1<<3)
196 #define INVOKE_COMMAND		(1<<4)
197 #define SETTING_VAR		(1<<5)
198 #define NEVER_SET		(1<<6)
199 #define GOT_FOCUS		(1<<7)
200 #define SCALE_DELETED		(1<<8)
201 
202 /*
203  * Symbolic values for the active parts of a slider. These are the values that
204  * may be returned by the ScaleElement procedure.
205  */
206 
207 #define OTHER		0
208 #define TROUGH1		1
209 #define SLIDER		2
210 #define TROUGH2		3
211 
212 /*
213  * Space to leave between scale area and text, and between text and edge of
214  * window.
215  */
216 
217 #define SPACING 2
218 
219 /*
220  * The tick values are all displayed with the same number of decimal places.
221  * This number of decimal places is such that the displayed values are all
222  * accurate to within the following proportion of a tick interval.
223  */
224 
225 #define TICK_VALUES_DISPLAY_ACCURACY 0.2
226 
227 /*
228  * Declaration of procedures used in the implementation of the scale widget.
229  */
230 
231 MODULE_SCOPE void	TkEventuallyRedrawScale(TkScale *scalePtr, int what);
232 MODULE_SCOPE double	TkRoundValueToResolution(TkScale *scalePtr, double value);
233 MODULE_SCOPE double	TkRoundIntervalToResolution(TkScale *scalePtr, double value);
234 MODULE_SCOPE TkScale *	TkpCreateScale(Tk_Window tkwin);
235 MODULE_SCOPE void	TkpDestroyScale(TkScale *scalePtr);
236 MODULE_SCOPE void	TkpDisplayScale(ClientData clientData);
237 MODULE_SCOPE int	TkpScaleElement(TkScale *scalePtr, int x, int y);
238 MODULE_SCOPE void	TkScaleSetValue(TkScale *scalePtr, double value,
239 			    int setVar, int invokeCommand);
240 MODULE_SCOPE double	TkScalePixelToValue(TkScale *scalePtr, int x, int y);
241 MODULE_SCOPE int	TkScaleValueToPixel(TkScale *scalePtr, double value);
242 
243 #endif /* _TKSCALE */
244