1
2/*
3 * Copyright 2006 The Android Open Source Project
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10#ifndef SkTextBox_DEFINED
11#define SkTextBox_DEFINED
12
13#include "SkCanvas.h"
14
15/** \class SkTextBox
16
17    SkTextBox is a helper class for drawing 1 or more lines of text
18    within a rectangle. The textbox is positioned and clipped by its Frame.
19    The Margin rectangle controls where the text is drawn relative to
20    the Frame. Line-breaks occur inside the Margin rectangle.
21
22    Spacing is a linear equation used to compute the distance between lines
23    of text. Spacing consists of two scalars: mul and add, and the spacing
24    between lines is computed as: spacing = paint.getTextSize() * mul + add
25*/
26class SkTextBox {
27public:
28    SkTextBox();
29
30    enum Mode {
31        kOneLine_Mode,
32        kLineBreak_Mode,
33
34        kModeCount
35    };
36    Mode    getMode() const { return (Mode)fMode; }
37    void    setMode(Mode);
38
39    enum SpacingAlign {
40        kStart_SpacingAlign,
41        kCenter_SpacingAlign,
42        kEnd_SpacingAlign,
43
44        kSpacingAlignCount
45    };
46    SpacingAlign    getSpacingAlign() const { return (SpacingAlign)fSpacingAlign; }
47    void            setSpacingAlign(SpacingAlign);
48
49    void    getBox(SkRect*) const;
50    void    setBox(const SkRect&);
51    void    setBox(SkScalar left, SkScalar top, SkScalar right, SkScalar bottom);
52
53    void    getSpacing(SkScalar* mul, SkScalar* add) const;
54    void    setSpacing(SkScalar mul, SkScalar add);
55
56    void    draw(SkCanvas*, const char text[], size_t len, const SkPaint&);
57
58    void    setText(const char text[], size_t len, const SkPaint&);
59    void    draw(SkCanvas*);
60    int     countLines() const;
61    SkScalar getTextHeight() const;
62
63private:
64    SkRect      fBox;
65    SkScalar    fSpacingMul, fSpacingAdd;
66    uint8_t     fMode, fSpacingAlign;
67    const char* fText;
68    size_t      fLen;
69    const SkPaint* fPaint;
70};
71
72class SkTextLineBreaker {
73public:
74    static int CountLines(const char text[], size_t len, const SkPaint&, SkScalar width);
75};
76
77#endif
78