summaryrefslogtreecommitdiff
path: root/osd.h
blob: aa8a35ab15a73aaede62fa6aea6e825e810ce7f6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
/*
 * osd.h: Abstract On Screen Display layer
 *
 * See the main source file 'vdr.c' for copyright information and
 * how to reach the author.
 *
 * $Id: osd.h 2.5 2010/01/17 13:23:50 kls Exp $
 */

#ifndef __OSD_H
#define __OSD_H

#include <limits.h>
#include <stdio.h>
#include <stdint.h>
#include "config.h"
#include "font.h"
#include "tools.h"

#define OSD_LEVEL_DEFAULT     0
#define OSD_LEVEL_SUBTITLES  10

#define MAXNUMCOLORS 256

enum {
                   //AARRGGBB
  clrTransparent = 0x00000000,
  clrGray50      = 0x7F000000, // 50% gray
  clrBlack       = 0xFF000000,
  clrRed         = 0xFFFC1414,
  clrGreen       = 0xFF24FC24,
  clrYellow      = 0xFFFCC024,
  clrMagenta     = 0xFFB000FC,
  clrBlue        = 0xFF0000FC,
  clrCyan        = 0xFF00FCFC,
  clrWhite       = 0xFFFCFCFC,
  };

enum eOsdError { oeOk, // see also OsdErrorTexts in osd.c
                 oeTooManyAreas,
                 oeTooManyColors,
                 oeBppNotSupported,
                 oeAreasOverlap,
                 oeWrongAlignment,
                 oeOutOfMemory,
                 oeWrongAreaSize,
                 oeUnknown,
               };

typedef uint32_t tColor; // see also font.h
typedef uint8_t tIndex;

class cPalette {
private:
  tColor color[MAXNUMCOLORS];
  int bpp;
  int maxColors, numColors;
  bool modified;
  double antiAliasGranularity;
protected:
  typedef tIndex tIndexes[MAXNUMCOLORS];
public:
  cPalette(int Bpp = 8);
        ///< Initializes the palette with the given color depth.
  virtual ~cPalette();
  void SetAntiAliasGranularity(uint FixedColors, uint BlendColors);
        ///< Allows the system to optimize utilization of the limited color
        ///< palette entries when generating blended colors for anti-aliasing.
        ///< FixedColors is the maximum number of colors used, and BlendColors
        ///< is the maximum number of foreground/background color combinations
        ///< used with anti-aliasing. If this function is not called with
        ///< useful values, the palette may be filled up with many shades of
        ///< a single color combination, and may not be able to serve all
        ///< requested colors. By default the palette assumes there will be
        ///< 10 fixed colors and 10 color combinations.
  int Bpp(void) const { return bpp; }
  void Reset(void);
        ///< Resets the palette, making it contain no colors.
  int Index(tColor Color);
        ///< Returns the index of the given Color (the first color has index 0).
        ///< If Color is not yet contained in this palette, it will be added if
        ///< there is a free slot. If the color can't be added to this palette,
        ///< the closest existing color will be returned.
  tColor Color(int Index) const { return Index < maxColors ? color[Index] : 0; }
        ///< Returns the color at the given Index. If Index is outside the valid
        ///< range, 0 will be returned.
  void SetBpp(int Bpp);
        ///< Sets the color depth of this palette to the given value.
        ///< The palette contents will be reset, so that it contains no colors.
  void SetColor(int Index, tColor Color);
        ///< Sets the palette entry at Index to Color. If Index is larger than
        ///< the number of currently used entries in this palette, the entries
        ///< in between will have undefined values.
  const tColor *Colors(int &NumColors) const;
        ///< Returns a pointer to the complete color table and stores the
        ///< number of valid entries in NumColors. If no colors have been
        ///< stored yet, NumColors will be set to 0 and the function will
        ///< return NULL.
  void Take(const cPalette &Palette, tIndexes *Indexes = NULL, tColor ColorFg = 0, tColor ColorBg = 0);
        ///< Takes the colors from the given Palette and adds them to this palette,
        ///< using existing entries if possible. If Indexes is given, it will be
        ///< filled with the index values that each color of Palette has in this
        ///< palette. If either of ColorFg or ColorBg is not zero, the first color
        ///< in Palette will be taken as ColorBg, and the second color will become
        ///< ColorFg.
  void Replace(const cPalette &Palette);
        ///< Replaces the colors of this palette with the colors from the given
        ///< palette.
  tColor Blend(tColor ColorFg, tColor ColorBg, uint8_t Level) const;
        ///< Determines a color that consists of a linear blend between ColorFg
        ///< and ColorBg. If Level is 0, the result is ColorBg, if it is 255,
        ///< the result is ColorFg. If SetAntiAliasGranularity() has been called previously,
        ///< Level will be mapped to a limited range of levels that allow to make best
        ///< use of the palette entries.
  int ClosestColor(tColor Color, int MaxDiff = INT_MAX) const;
        ///< Returns the index of a color in this palette that is closest to the given
        ///< Color. MaxDiff can be used to control the maximum allowed color difference.
        ///< If no color with a maximum difference of MaxDiff can be found, -1 will
        ///< be returned. With the default value of INT_MAX, there will always be
        ///< a valid color index returned, but the color may be completely different.
  };

enum eTextAlignment { taCenter  = 0x00,
                      taLeft    = 0x01,
                      taRight   = 0x02,
                      taTop     = 0x04,
                      taBottom  = 0x08,
                      taDefault = taTop | taLeft
                    };

class cFont;

class cBitmap : public cPalette {
private:
  tIndex *bitmap;
  int x0, y0;
  int width, height;
  int dirtyX1, dirtyY1, dirtyX2, dirtyY2;
public:
  cBitmap(int Width, int Height, int Bpp, int X0 = 0, int Y0 = 0);
       ///< Creates a bitmap with the given Width, Height and color depth (Bpp).
       ///< X0 and Y0 define the offset at which this bitmap will be located on the OSD.
       ///< All coordinates given in the other functions will be relative to
       ///< this offset (unless specified otherwise).
  cBitmap(const char *FileName);
       ///< Creates a bitmap and loads an XPM image from the given file.
  cBitmap(const char *const Xpm[]);
       ///< Creates a bitmap from the given XPM data.
  virtual ~cBitmap();
  int X0(void) const { return x0; }
  int Y0(void) const { return y0; }
  int Width(void) const { return width; }
  int Height(void) const { return height; }
  void SetSize(int Width, int Height);
       ///< Sets the size of this bitmap to the given values. Any previous
       ///< contents of the bitmap will be lost. If Width and Height are the same
       ///< as the current values, nothing will happen and the bitmap remains
       ///< unchanged.
  bool Contains(int x, int y) const;
       ///< Returns true if this bitmap contains the point (x, y).
  bool Covers(int x1, int y1, int x2, int y2) const;
       ///< Returns true if the rectangle defined by the given coordinates
       ///< completely covers this bitmap.
  bool Intersects(int x1, int y1, int x2, int y2) const;
       ///< Returns true if the rectangle defined by the given coordinates
       ///< intersects with this bitmap.
  bool Dirty(int &x1, int &y1, int &x2, int &y2);
       ///< Tells whether there is a dirty area and returns the bounding
       ///< rectangle of that area (relative to the bitmaps origin).
  void Clean(void);
       ///< Marks the dirty area as clean.
  bool LoadXpm(const char *FileName);
       ///< Calls SetXpm() with the data from the file FileName.
       ///< Returns true if the operation was successful.
  bool SetXpm(const char *const Xpm[], bool IgnoreNone = false);
       ///< Sets this bitmap to the given XPM data. Any previous bitmap or
       ///< palette data will be overwritten with the new data.
       ///< If IgnoreNone is true, a "none" color entry will be ignored.
       ///< Only set IgnoreNone to true if you know that there is a "none"
       ///< color entry in the XPM data and that this entry is not used!
       ///< If SetXpm() is called with IgnoreNone set to false and the XPM
       ///< data contains an unused "none" entry, it will be automatically
       ///< called again with IgnoreNone set to true.
       ///< Returns true if the operation was successful.
  void SetIndex(int x, int y, tIndex Index);
       ///< Sets the index at the given coordinates to Index.
       ///< Coordinates are relative to the bitmap's origin.
  void DrawPixel(int x, int y, tColor Color);
       ///< Sets the pixel at the given coordinates to the given Color, which is
       ///< a full 32 bit ARGB value.
       ///< If the coordinates are outside the bitmap area, no pixel will be set.
  void DrawBitmap(int x, int y, const cBitmap &Bitmap, tColor ColorFg = 0, tColor ColorBg = 0, bool ReplacePalette = false, bool Overlay = false);
       ///< Sets the pixels in this bitmap with the data from the given
       ///< Bitmap, putting the upper left corner of the Bitmap at (x, y).
       ///< If ColorFg or ColorBg is given, the first palette entry of the Bitmap
       ///< will be mapped to ColorBg and the second palette entry will be mapped to
       ///< ColorFg (palette indexes are defined so that 0 is the background and
       ///< 1 is the foreground color). ReplacePalette controls whether the target
       ///< area shall have its palette replaced with the one from Bitmap.
       ///< If Overlay is true, any pixel in Bitmap that has color index 0 will
       ///< not overwrite the corresponding pixel in the target area.
  void DrawText(int x, int y, const char *s, tColor ColorFg, tColor ColorBg, const cFont *Font, int Width = 0, int Height = 0, int Alignment = taDefault);
       ///< Draws the given string at coordinates (x, y) with the given foreground
       ///< and background color and font. If Width and Height are given, the text
       ///< will be drawn into a rectangle with the given size and the given
       ///< Alignment (default is top-left). If ColorBg is clrTransparent, no
       ///< background pixels will be drawn, which allows drawing "transparent" text.
  void DrawRectangle(int x1, int y1, int x2, int y2, tColor Color);
       ///< Draws a filled rectangle defined by the upper left (x1, y1) and lower right
       ///< (x2, y2) corners with the given Color. If the rectangle covers the entire
       ///< bitmap area, the color palette will be reset, so that new colors can be
       ///< used for drawing.
  void DrawEllipse(int x1, int y1, int x2, int y2, tColor Color, int Quadrants = 0);
       ///< Draws a filled ellipse defined by the upper left (x1, y1) and lower right
       ///< (x2, y2) corners with the given Color. Quadrants controls which parts of
       ///< the ellipse are actually drawn:
       ///< 0       draws the entire ellipse
       ///< 1..4    draws only the first, second, third or fourth quadrant, respectively
       ///< 5..8    draws the right, top, left or bottom half, respectively
       ///< -1..-8  draws the inverted part of the given quadrant(s)
       ///< If Quadrants is not 0, the coordinates are those of the actual area, not
       ///< the full circle!
  void DrawSlope(int x1, int y1, int x2, int y2, tColor Color, int Type);
       ///< Draws a "slope" into the rectangle defined by the upper left (x1, y1) and
       ///< lower right (x2, y2) corners with the given Color. Type controls the
       ///< direction of the slope and which side of it will be drawn:
       ///< 0: horizontal, rising,  lower
       ///< 1: horizontal, rising,  upper
       ///< 2: horizontal, falling, lower
       ///< 3: horizontal, falling, upper
       ///< 4: vertical,   rising,  lower
       ///< 5: vertical,   rising,  upper
       ///< 6: vertical,   falling, lower
       ///< 7: vertical,   falling, upper
  const tIndex *Data(int x, int y) const;
       ///< Returns the address of the index byte at the given coordinates.
  tColor GetColor(int x, int y) const { return Color(*Data(x, y)); }
       ///< Returns the color at the given coordinates.
  void ReduceBpp(const cPalette &Palette);
       ///< Reduces the color depth of the bitmap to that of the given Palette.
       ///< If Palette's color depth is not smaller than the bitmap's current
       ///< color depth, or if it is not one of 4bpp or 2bpp, nothing happens. After
       ///< reducing the color depth the current palette is replaced with
       ///< the given one.
  void ShrinkBpp(int NewBpp);
       ///< Shrinks the color depth of the bitmap to NewBpp by keeping only
       ///< the 2^NewBpp most frequently used colors as defined in the current palette.
       ///< If NewBpp is not smaller than the bitmap's current color depth,
       ///< or if it is not one of 4bpp or 2bpp, nothing happens.
  };

struct tArea {
  int x1, y1, x2, y2;
  int bpp;
  int Width(void) const { return x2 - x1 + 1; }
  int Height(void) const { return y2 - y1 + 1; }
  bool Intersects(const tArea &Area) const { return !(x2 < Area.x1 || x1 > Area.x2 || y2 < Area.y1 || y1 > Area.y2); }
  };

#define MAXOSDAREAS 16

class cOsd {
  friend class cOsdProvider;
private:
  static int osdLeft, osdTop, osdWidth, osdHeight;
  static cVector<cOsd *> Osds;
  cBitmap *savedRegion;
  cBitmap *bitmaps[MAXOSDAREAS];
  int numBitmaps;
  int left, top, width, height;
  uint level;
  bool active;
protected:
  cOsd(int Left, int Top, uint Level);
       ///< Initializes the OSD with the given coordinates.
       ///< By default it is assumed that the full area will be able to display
       ///< full 32 bit graphics (ARGB with eight bit for each color and the alpha
       ///< value, repectively). However, the actual hardware in use may not be
       ///< able to display such a high resolution OSD, so there is an option to
       ///< divide the full OSD area into several sub-areas with lower color depths
       ///< and individual palettes. The sub-areas need not necessarily cover the
       ///< entire OSD area, but only the OSD area actually covered by sub-areas
       ///< will be available for drawing.
       ///< At least one area must be defined in order to set the actual width and
       ///< height of the OSD. Also, the caller must first try to use an area that
       ///< consists of only one sub-area that covers the entire drawing space,
       ///< and should require only the minimum necessary color depth. This is
       ///< because a derived cOsd class may or may not be able to handle more
       ///< than one area.
       ///< There can be any number of cOsd objects at the same time, but only
       ///< one of them will be active at any given time. The active OSD is the
       ///< one with the lowest value of Level. If there are several cOsd objects
       ///< with the same Level, the one that was created first will be active.
  bool Active(void) { return active; }
  virtual void SetActive(bool On) { active = On; }
       ///< Sets this OSD to be the active one.
       ///< A derived class must call cOsd::SetActive(On).
public:
  virtual ~cOsd();
       ///< Shuts down the OSD.
  static int OsdLeft(void) { return osdLeft ? osdLeft : Setup.OSDLeft; }
  static int OsdTop(void) { return osdTop ? osdTop : Setup.OSDTop; }
  static int OsdWidth(void) { return osdWidth ? osdWidth : Setup.OSDWidth; }
  static int OsdHeight(void) { return osdHeight ? osdHeight : Setup.OSDHeight; }
  static void SetOsdPosition(int Left, int Top, int Width, int Height);
       ///< Sets the position and size of the OSD to the given values.
       ///< This may be useful for plugins that determine the scaling of the
       ///< video image and need to scale the OSD accordingly to fit on the
       ///< screen.
  static int IsOpen(void) { return Osds.Size() && Osds[0]->level == OSD_LEVEL_DEFAULT; }
       ///< Returns true if there is currently a level 0 OSD open.
  int Left(void) { return left; }
  int Top(void) { return top; }
  int Width(void) { return width; }
  int Height(void) { return height; }
  void SetAntiAliasGranularity(uint FixedColors, uint BlendColors);
       ///< Allows the system to optimize utilization of the limited color
       ///< palette entries when generating blended colors for anti-aliasing.
       ///< FixedColors is the maximum number of colors used, and BlendColors
       ///< is the maximum number of foreground/background color combinations
       ///< used with anti-aliasing. If this function is not called with
       ///< useful values, the palette may be filled up with many shades of
       ///< a single color combination, and may not be able to serve all
       ///< requested colors. By default the palette assumes there will be
       ///< 10 fixed colors and 10 color combinations.
  cBitmap *GetBitmap(int Area);
       ///< Returns a pointer to the bitmap for the given Area, or NULL if no
       ///< such bitmap exists.
  virtual eOsdError CanHandleAreas(const tArea *Areas, int NumAreas);
       ///< Checks whether the OSD can display the given set of sub-areas.
       ///< The return value indicates whether a call to SetAreas() with this
       ///< set of areas will succeed. CanHandleAreas() may be called with an
       ///< OSD that is already in use with other areas and will not interfere
       ///< with the current operation of the OSD.
       ///< A derived class must first call the base class CanHandleAreas()
       ///< to check the basic conditions, like not overlapping etc.
  virtual eOsdError SetAreas(const tArea *Areas, int NumAreas);
       ///< Sets the sub-areas to the given areas.
       ///< The return value indicates whether the operation was successful.
       ///< If an error is reported, nothing will have changed and the previous
       ///< OSD (if any) will still be displayed as before.
       ///< If the OSD has been divided into several sub-areas, all areas that
       ///< are part of the rectangle that surrounds a given drawing operation
       ///< will be drawn into, with the proper offsets.
       ///< A new call overwrites any previous settings
  virtual void SaveRegion(int x1, int y1, int x2, int y2);
       ///< Saves the region defined by the given coordinates for later restoration
       ///< through RestoreRegion(). Only one saved region can be active at any
       ///< given time.
  virtual void RestoreRegion(void);
       ///< Restores the region previously saved by a call to SaveRegion().
       ///< If SaveRegion() has not been called before, nothing will happen.
  virtual eOsdError SetPalette(const cPalette &Palette, int Area);
       ///< Sets the Palette for the given Area (the first area is numbered 0).
  virtual void DrawPixel(int x, int y, tColor Color);
       ///< Sets the pixel at the given coordinates to the given Color, which is
       ///< a full 32 bit ARGB value.
       ///< If the OSD area has been divided into separate sub-areas, and the
       ///< given coordinates don't fall into any of these sub-areas, no pixel will
       ///< be set.
  virtual void DrawBitmap(int x, int y, const cBitmap &Bitmap, tColor ColorFg = 0, tColor ColorBg = 0, bool ReplacePalette = false, bool Overlay = false);
       ///< Sets the pixels in the OSD with the data from the given
       ///< Bitmap, putting the upper left corner of the Bitmap at (x, y).
       ///< If ColorFg or ColorBg is given, the first palette entry of the Bitmap
       ///< will be mapped to ColorBg and the second palette entry will be mapped to
       ///< ColorFg (palette indexes are defined so that 0 is the background and
       ///< 1 is the foreground color). ReplacePalette controls whether the target
       ///< area shall have its palette replaced with the one from Bitmap.
       ///< If Overlay is true, any pixel in Bitmap that has color index 0 will
       ///< not overwrite the corresponding pixel in the target area.
  virtual void DrawText(int x, int y, const char *s, tColor ColorFg, tColor ColorBg, const cFont *Font, int Width = 0, int Height = 0, int Alignment = taDefault);
       ///< Draws the given string at coordinates (x, y) with the given foreground
       ///< and background color and font. If Width and Height are given, the text
       ///< will be drawn into a rectangle with the given size and the given
       ///< Alignment (default is top-left). If ColorBg is clrTransparent, no
       ///< background pixels will be drawn, which allows drawing "transparent" text.
  virtual void DrawRectangle(int x1, int y1, int x2, int y2, tColor Color);
       ///< Draws a filled rectangle defined by the upper left (x1, y1) and lower right
       ///< (x2, y2) corners with the given Color.
  virtual void DrawEllipse(int x1, int y1, int x2, int y2, tColor Color, int Quadrants = 0);
       ///< Draws a filled ellipse defined by the upper left (x1, y1) and lower right
       ///< (x2, y2) corners with the given Color. Quadrants controls which parts of
       ///< the ellipse are actually drawn:
       ///< 0       draws the entire ellipse
       ///< 1..4    draws only the first, second, third or fourth quadrant, respectively
       ///< 5..8    draws the right, top, left or bottom half, respectively
       ///< -1..-8  draws the inverted part of the given quadrant(s)
       ///< If Quadrants is not 0, the coordinates are those of the actual area, not
       ///< the full circle!
  virtual void DrawSlope(int x1, int y1, int x2, int y2, tColor Color, int Type);
       ///< Draws a "slope" into the rectangle defined by the upper left (x1, y1) and
       ///< lower right (x2, y2) corners with the given Color. Type controls the
       ///< direction of the slope and which side of it will be drawn:
       ///< 0: horizontal, rising,  lower
       ///< 1: horizontal, rising,  upper
       ///< 2: horizontal, falling, lower
       ///< 3: horizontal, falling, upper
       ///< 4: vertical,   rising,  lower
       ///< 5: vertical,   rising,  upper
       ///< 6: vertical,   falling, lower
       ///< 7: vertical,   falling, upper
  virtual void Flush(void);
       ///< Actually commits all data to the OSD hardware.
  };

class cOsdProvider {
private:
  static cOsdProvider *osdProvider;
  static int oldWidth;
  static int oldHeight;
  static double oldAspect;
protected:
  virtual cOsd *CreateOsd(int Left, int Top, uint Level) = 0;
      ///< Returns a pointer to a newly created cOsd object, which will be located
      ///< at the given coordinates.
public:
  cOsdProvider(void);
      //XXX maybe parameter to make this one "sticky"??? (frame-buffer etc.)
  virtual ~cOsdProvider();
  static cOsd *NewOsd(int Left, int Top, uint Level = OSD_LEVEL_DEFAULT);
      ///< Returns a pointer to a newly created cOsd object, which will be located
      ///< at the given coordinates. When the cOsd object is no longer needed, the
      ///< caller must delete it. If the OSD is already in use, or there is no OSD
      ///< provider, a dummy OSD is returned so that the caller may always use the
      ///< returned pointer without having to check it every time it is accessed.
  static void UpdateOsdSize(bool Force = false);
      ///< Inquires the actual size of the video display and adjusts the OSD and
      ///< font sizes accordingly. If Force is true, all settings are recalculated,
      ///< even if the video resolution hasn't changed since the last call to
      ///< this funtion.
  static void Shutdown(void);
      ///< Shuts down the OSD provider facility by deleting the current OSD provider.
  };

class cTextScroller {
private:
  cOsd *osd;
  int left, top, width, height;
  const cFont *font;
  tColor colorFg, colorBg;
  int offset, shown;
  cTextWrapper textWrapper;
  void DrawText(void);
public:
  cTextScroller(void);
  cTextScroller(cOsd *Osd, int Left, int Top, int Width, int Height, const char *Text, const cFont *Font, tColor ColorFg, tColor ColorBg);
  void Set(cOsd *Osd, int Left, int Top, int Width, int Height, const char *Text, const cFont *Font, tColor ColorFg, tColor ColorBg);
  void Reset(void);
  int Left(void) { return left; }
  int Top(void) { return top; }
  int Width(void) { return width; }
  int Height(void) { return height; }
  int Total(void) { return textWrapper.Lines(); }
  int Offset(void) { return offset; }
  int Shown(void) { return shown; }
  bool CanScroll(void) { return CanScrollUp() || CanScrollDown(); }
  bool CanScrollUp(void) { return offset > 0; }
  bool CanScrollDown(void) { return offset + shown < Total(); }
  void Scroll(bool Up, bool Page);
  };

#endif //__OSD_H