src/kits/interface/textview_support/LineBuffer.h

   1 /*
   2  * Copyright 2001-2006, Haiku, Inc. All Rights Reserved.
   3  * Distributed under the terms of the MIT License.
   4  *
   5  * Authors:
   6  *              Marc Flerackers (mflerackers@androme.be)
   7  */
   8 #ifndef __LINE_BUFFER_H
   9 #define __LINE_BUFFER_H
  10
  11
  12 #include <SupportDefs.h>
  13 #include <TextView.h>
  14
  15 #include "TextViewSupportBuffer.h"
  16
  17 struct STELine {
  18         long            offset;         // offset of first character of line
  19         float           origin;         // pixel position of top of line
  20         float           ascent;         // maximum ascent for line
  21         float           width;          // cached width of line in pixels
  22 };
  23
  24
  25 class BTextView::LineBuffer : public _BTextViewSupportBuffer_<STELine> {
  26
  27 public:
  28                                                                 LineBuffer();
  29         virtual                                         ~LineBuffer();
  30
  31                         void                            InsertLine(STELine* inLine, int32 index);
  32                         void                            RemoveLines(int32 index, int32 count = 1);
  33                         void                            RemoveLineRange(int32 fromOffset,
  34                                                                         int32 toOffset);
  35
  36                         int32                           OffsetToLine(int32 offset) const;
  37                         int32                           PixelToLine(float pixel) const;
  38
  39                         void                            BumpOrigin(float delta, int32 index);
  40                         void                            BumpOffset(int32 delta, int32 index);
  41
  42                         int32                           NumLines() const;
  43                         float                           MaxWidth() const;
  44                         STELine*                        operator[](int32 index) const;
  45 };
  46
  47
  48 inline int32
  49 BTextView::LineBuffer::NumLines() const
  50 {
  51         return fItemCount - 1;
  52 }
  53
  54
  55 inline STELine *
  56 BTextView::LineBuffer::operator[](int32 index) const
  57 {
  58         return &fBuffer[index];
  59 }
  60
  61
  62 #endif  // __LINE_BUFFER_H