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
|
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Fraction</title>
<link rel="help" href="https://w3c.github.io/mathml-core/#fractions-mfrac">
<link rel="help" href="https://w3c.github.io/mathml-core/#fraction-with-nonzero-line-thickness">
<link rel="help" href="https://w3c.github.io/mathml-core/#fraction-with-zero-line-thickness">
<meta name="assert" content="Verify fraction metrics for different sizes of numerator and denominator.">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/mathml/support/feature-detection.js"></script>
<script src="/mathml/support/fonts.js"></script>
<link rel="stylesheet" type="text/css" href="/fonts/ahem.css" />
<style>
math, mspace {
/* OS/2.sxHeight = 800 */
/* post.underlineThickness == 20 */
font-family: Ahem;
font-size: 10px;
}
div.shrink-wrap {
background: yellow;
display: inline-block;
margin-top: 5px;
padding-top: 5px;
}
</style>
<script>
const xHeight = 800;
const underlineThickness = 800;
const emToPx = 10 / 1000; // font-size: 10px, font.em = 1000
function getBox(aId) {
var box = document.getElementById(aId).getBoundingClientRect();
box.middle = (box.bottom + box.top) / 2;
box.center = (box.left + box.right) / 2;
return box;
}
setup({ explicit_done: true });
window.addEventListener("load", () => { loadAllFonts().then(runTests); });
function runTests() {
test(function() {
assert_true(MathMLFeatureDetection.has_mspace());
var e = 4;
var mathAxis = getBox("baseline").top - (xHeight/2) * emToPx;
for (var i = 0; i <= 4; i++) {
var frac = getBox("frac" + i);
var num = getBox("frac" + i + "num");
var den = getBox("frac" + i + "den");
// To estimate the fraction axis, we calculate barycenter between the
// top and bottom of the fraction, using the heights of numerator and
// denominator as weights.
var fracAxis = (frac.top * den.height + frac.bottom * num.height) / (num.height + den.height);
assert_approx_equals(fracAxis, mathAxis, e, "frac" + i + " fraction bar");
}
}, "Fraction axis is aligned on the math axis");
test(function() {
assert_true(MathMLFeatureDetection.has_mspace());
for (var i = 0; i < 10; i++) {
assert_less_than_equal(getBox("frac" + i + "num").bottom, getBox("frac" + i + "den").top, "numerator is above denominator");
assert_less_than(getBox("frac" + i + "den").top - getBox("frac" + i + "num").bottom, 5, "The gap between numerator and denominator is not too large");
}
}, "Vertical positions of numerator and denominator");
test(function() {
assert_true(MathMLFeatureDetection.has_mspace());
var e = 3;
for (var i = 0; i < 10; i++)
assert_approx_equals(getBox("frac" + i + "num").center, getBox("frac" + i + "den").center, e, "numerator and denominator are horizontally centered");
}, "Horizontal alignments of numerator and denominator");
test(function() {
assert_true(MathMLFeatureDetection.has_mspace());
var e = 5;
for (var i = 0; i < 10; i++) {
var frac = getBox("frac" + i);
var num = getBox("frac" + i + "num");
var den = getBox("frac" + i + "den");
assert_approx_equals(frac.height, den.bottom - num.top, e, "height of frac " + i + " is determined by the bottom/top sides of the denominator/numerator");
assert_approx_equals(frac.width, Math.max(num.right, den.right) - Math.min(num.left, den.left), e, "width of frac " + i + " is determined by the left/right sides of the denominator/numerator (plus some spacing)");
}
}, "Dimension of mfrac elements");
test(function() {
assert_true(MathMLFeatureDetection.has_mspace());
assert_true(MathMLFeatureDetection.has_mfrac());
Array.from(document.getElementsByClassName("shrink-wrap")).forEach((container) => {
var marginPx = 2; // By default fractions have 1px margin on each side.
var epsilon = 1;
var containerWidth = container.getBoundingClientRect().width;
var children = container.getElementsByTagName("mspace");
var numWidth = children[0].getBoundingClientRect().width;
var denWidth = children[1].getBoundingClientRect().width;
assert_approx_equals(containerWidth, marginPx + Math.max(numWidth, denWidth), epsilon, "Should be the maximum preferred width of numerator/denominator.");
});
}, "Preferred width of mfrac elements");
done();
}
</script>
</head>
<body>
<div id="log"></div>
<p>
<math>
<mspace id="baseline" width="1em" height="0em" depth="1em" style="background: black"/>
<mfrac id="frac0">
<mspace id="frac0num" width="15px" height="15px" style="background: blue"/>
<mspace id="frac0den" width="15px" height="15px" style="background: green"/>
</mfrac>
<mfrac id="frac1">
<mspace id="frac1num" width="30px" height="15px" style="background: blue"/>
<mspace id="frac1den" width="15px" height="15px" style="background: green"/>
</mfrac>
<mfrac id="frac2">
<mspace id="frac2num" width="15px" height="15px" style="background: blue"/>
<mspace id="frac2den" width="30px" height="15px" style="background: green"/>
</mfrac>
<mfrac id="frac3">
<mspace id="frac3num" width="15px" height="30px" style="background: blue"/>
<mspace id="frac3den" width="15px" height="15px" style="background: green"/>
</mfrac>
<mfrac id="frac4">
<mspace id="frac4num" width="15px" height="15px" style="background: blue"/>
<mspace id="frac4den" width="15px" height="30px" style="background: green"/>
</mfrac>
<mfrac id="frac5" linethickness="0px">
<mspace id="frac5num" width="15px" height="15px" style="background: blue"/>
<mspace id="frac5den" width="15px" height="15px" style="background: green"/>
</mfrac>
<mfrac id="frac6" linethickness="0px">
<mspace id="frac6num" width="30px" height="15px" style="background: blue"/>
<mspace id="frac6den" width="15px" height="15px" style="background: green"/>
</mfrac>
<mfrac id="frac7" linethickness="0px">
<mspace id="frac7num" width="15px" height="15px" style="background: blue"/>
<mspace id="frac7den" width="30px" height="15px" style="background: green"/>
</mfrac>
<mfrac id="frac8" linethickness="0px">
<mspace id="frac8num" width="15px" height="30px" style="background: blue"/>
<mspace id="frac8den" width="15px" height="15px" style="background: green"/>
</mfrac>
<mfrac id="frac9" linethickness="0px">
<mspace id="frac9num" width="15px" height="15px" style="background: blue"/>
<mspace id="frac9den" width="15px" height="30px" style="background: green"/>
</mfrac>
</math>
</p>
<div class="shrink-wrap">
<math>
<mfrac>
<mspace width="30px" height="15px" style="background: blue"/>
<mspace width="15px" height="15px" style="background: green"/>
</mfrac>
</math>
</div>
<div class="shrink-wrap">
<math>
<mfrac>
<mspace width="15px" height="15px" style="background: blue"/>
<mspace width="30px" height="15px" style="background: green"/>
</mfrac>
</math>
</div>
<div class="shrink-wrap">
<math>
<mfrac linethickness="0px">
<mspace width="30px" height="15px" style="background: blue"/>
<mspace width="15px" height="15px" style="background: green"/>
</mfrac>
</math>
</div>
<div class="shrink-wrap">
<math>
<mfrac linethickness="0px">
<mspace width="15px" height="15px" style="background: blue"/>
<mspace width="30px" height="15px" style="background: green"/>
</mfrac>
</math>
</div>
</body>
</html>
|
