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
|
/*
* This file is part of the CSS implementation for KDE.
*
* Copyright (C) 1999-2003 Lars Knoll ([email protected])
* (C) David Carson <[email protected]>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#include "helper.h"
#include "tdehtmllayout.h"
#include <tqmap.h>
#include <tqpainter.h>
#include <dom/dom_string.h>
#include <xml/dom_stringimpl.h>
#include <rendering/render_object.h>
#include <tqptrlist.h>
#include <kstaticdeleter.h>
#include <tdeapplication.h>
#include <tdeconfig.h>
#include <tqtooltip.h>
using namespace DOM;
using namespace tdehtml;
namespace tdehtml {
TQPainter *printpainter;
}
void tdehtml::setPrintPainter( TQPainter *printer )
{
printpainter = printer;
}
double calcHue(double temp1, double temp2, double hueVal)
{
if (hueVal < 0)
hueVal++;
else if (hueVal > 1)
hueVal--;
if (hueVal * 6 < 1)
return temp1 + (temp2 - temp1) * hueVal * 6;
if (hueVal * 2 < 1)
return temp2;
if (hueVal * 3 < 2)
return temp1 + (temp2 - temp1) * (2.0 / 3.0 - hueVal) * 6;
return temp1;
}
// Explanation of this algorithm can be found in the CSS3 Color Module
// specification at http://www.w3.org/TR/css3-color/#hsl-color with further
// explanation available at http://en.wikipedia.org/wiki/HSL_color_space
// all values are in the range of 0 to 1.0
TQRgb tdehtml::tqRgbaFromHsla(double h, double s, double l, double a)
{
double temp2 = l < 0.5 ? l * (1.0 + s) : l + s - l * s;
double temp1 = 2.0 * l - temp2;
return tqRgba(calcHue(temp1, temp2, h + 1.0 / 3.0) * 255, calcHue(temp1, temp2, h) * 255, calcHue(temp1, temp2, h - 1.0 / 3.0) * 255, a * 255);
}
/** finds out the background color of an element
* @param obj render object
* @return the background color. It is guaranteed that a valid color is returned.
*/
TQColor tdehtml::retrieveBackgroundColor(const RenderObject *obj)
{
TQColor result;
while (!obj->isCanvas()) {
result = obj->style()->backgroundColor();
if (result.isValid()) return result;
obj = obj->container();
}/*wend*/
// everything transparent? Use base then.
return obj->style()->palette().active().base();
}
/** checks whether the given colors have enough contrast
* @returns @p true if contrast is ok.
*/
bool tdehtml::hasSufficientContrast(const TQColor &c1, const TQColor &c2)
{
// New version from Germain Garand, better suited for contrast measurement
#if 1
#define HUE_DISTANCE 40
#define CONTRAST_DISTANCE 10
int h1, s1, v1, h2, s2, v2;
int hdist = -CONTRAST_DISTANCE;
c1.hsv(&h1,&s1,&v1);
c2.hsv(&h2,&s2,&v2);
if(h1!=-1 && h2!=-1) { // grey values have no hue
hdist = kAbs(h1-h2);
if (hdist > 180) hdist = 360-hdist;
if (hdist < HUE_DISTANCE) {
hdist -= HUE_DISTANCE;
// see if they are high key or low key colours
bool hk1 = h1>=45 && h1<=225;
bool hk2 = h2>=45 && h2<=225;
if (hk1 && hk2)
hdist = (5*hdist)/3;
else if (!hk1 && !hk2)
hdist = (7*hdist)/4;
}
hdist = kMin(hdist, HUE_DISTANCE*2);
}
return hdist + (kAbs(s1-s2)*128)/(160+kMin(s1,s2)) + kAbs(v1-v2) > CONTRAST_DISTANCE;
#undef CONTRAST_DISTANCE
#undef HUE_DISTANCE
#else // orginal fast but primitive version by me (LS)
// ### arbitrary value, to be adapted if necessary (LS)
#define CONTRAST_DISTANCE 32
if (kAbs(c1.red() - c2.red()) > CONTRAST_DISTANCE) return true;
if (kAbs(c1.green() - c2.green()) > CONTRAST_DISTANCE) return true;
if (kAbs(c1.blue() - c2.blue()) > CONTRAST_DISTANCE) return true;
return false;
#undef CONTRAST_DISTANCE
#endif
}
|
