added support for alpha channel to wxColour to/from string conversion functions ...
[wxWidgets.git] / src / common / colourcmn.cpp
1 /////////////////////////////////////////////////////////////////////////////
2 // Name: src/common/colourcmn.cpp
3 // Purpose: wxColourBase implementation
4 // Author: Francesco Montorsi
5 // Modified by:
6 // Created: 20/4/2006
7 // RCS-ID: $Id$
8 // Copyright: (c) Francesco Montorsi
9 // Licence: wxWindows licence
10 /////////////////////////////////////////////////////////////////////////////
11
12
13 // For compilers that support precompilation, includes "wx.h".
14 #include "wx/wxprec.h"
15
16 #ifdef __BORLANDC__
17 #pragma hdrstop
18 #endif
19
20 #include "wx/colour.h"
21
22 #ifndef WX_PRECOMP
23 #include "wx/log.h"
24 #include "wx/utils.h"
25 #include "wx/gdicmn.h"
26 #include "wx/wxcrtvararg.h"
27 #endif
28
29 #if wxUSE_VARIANT
30 IMPLEMENT_VARIANT_OBJECT_EXPORTED(wxColour,WXDLLEXPORT)
31 #endif
32
33 // ============================================================================
34 // wxString <-> wxColour conversions
35 // ============================================================================
36
37 bool wxColourBase::FromString(const wxString& str)
38 {
39 if ( str.empty() )
40 return false; // invalid or empty string
41
42 if ( wxStrnicmp(str, wxT("RGB"), 3) == 0 )
43 {
44 // CSS-like RGB specification
45 // according to http://www.w3.org/TR/css3-color/#colorunits
46 // values outside 0-255 range are allowed but should be clipped
47 int red, green, blue,
48 alpha = wxALPHA_OPAQUE;
49 if ( str.length() > 3 && (str[3] == wxT('a') || str[3] == wxT('A')) )
50 {
51 float a;
52 // TODO: use locale-independent function
53 if ( wxSscanf(str.wx_str() + 4, wxT("( %d , %d , %d , %f )"),
54 &red, &green, &blue, &a) != 4 )
55 return false;
56
57 alpha = wxRound(a * 255);
58 }
59 else // no 'a' following "rgb"
60 {
61 if ( wxSscanf(str.wx_str() + 3, wxT("( %d , %d , %d )"),
62 &red, &green, &blue) != 3 )
63 return false;
64 }
65
66 Set((unsigned char)wxClip(red, 0, 255),
67 (unsigned char)wxClip(green, 0, 255),
68 (unsigned char)wxClip(blue, 0, 255),
69 (unsigned char)wxClip(alpha, 0, 255));
70 }
71 else if ( str[0] == wxT('#') && wxStrlen(str) == 7 )
72 {
73 // hexadecimal prefixed with # (HTML syntax)
74 unsigned long tmp;
75 if (wxSscanf(str.wx_str() + 1, wxT("%lx"), &tmp) != 1)
76 return false;
77
78 Set((unsigned char)(tmp >> 16),
79 (unsigned char)(tmp >> 8),
80 (unsigned char)tmp);
81 }
82 else if (wxTheColourDatabase) // a colour name ?
83 {
84 // we can't do
85 // *this = wxTheColourDatabase->Find(str)
86 // because this place can be called from constructor
87 // and 'this' could not be available yet
88 wxColour clr = wxTheColourDatabase->Find(str);
89 if (clr.Ok())
90 Set((unsigned char)clr.Red(),
91 (unsigned char)clr.Green(),
92 (unsigned char)clr.Blue());
93 }
94
95 if (Ok())
96 return true;
97
98 wxLogDebug(wxT("wxColour::Set - couldn't set to colour string '%s'"), str);
99 return false;
100 }
101
102 wxString wxColourBase::GetAsString(long flags) const
103 {
104 wxString colName;
105
106 const bool isOpaque = Alpha() == wxALPHA_OPAQUE;
107
108 // we can't use the name format if the colour is not opaque as the alpha
109 // information would be lost
110 if ( (flags & wxC2S_NAME) && isOpaque )
111 {
112 colName = wxTheColourDatabase->FindName(
113 wx_static_cast(const wxColour &, *this)).MakeLower();
114 }
115
116 if ( colName.empty() )
117 {
118 const int red = Red(),
119 blue = Blue(),
120 green = Green();
121
122 if ( flags & wxC2S_CSS_SYNTAX )
123 {
124 // no name for this colour; return it in CSS syntax
125 if ( isOpaque )
126 {
127 colName.Printf(wxT("rgb(%d, %d, %d)"), red, green, blue);
128 }
129 else // use rgba() form
130 {
131 // TODO: use locale-independent function
132 colName.Printf(wxT("rgba(%d, %d, %d, %.3f)"),
133 red, green, blue, Alpha() / 255.);
134 }
135 }
136 else if ( flags & wxC2S_HTML_SYNTAX )
137 {
138 wxASSERT_MSG( isOpaque, "alpha is lost in HTML syntax" );
139
140 // no name for this colour; return it in HTML syntax
141 colName.Printf(wxT("#%02X%02X%02X"), red, green, blue);
142 }
143 }
144
145 // this function should alway returns a non-empty string
146 wxASSERT_MSG(!colName.empty(),
147 wxT("Invalid wxColour -> wxString conversion flags"));
148
149 return colName;
150 }
151
152 #if WXWIN_COMPATIBILITY_2_6
153
154 // static
155 wxColour wxColourBase::CreateByName(const wxString& name)
156 {
157 return wxColour(name);
158 }
159
160 void wxColourBase::InitFromName(const wxString& col)
161 {
162 Set(col);
163 }
164
165 #endif // WXWIN_COMPATIBILITY_2_6