1// Copyright (C) 2023 The Qt Company Ltd.
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4#include "qsgcurveglyphatlas_p.h"
5#include "qsgcurvefillnode_p.h"
6#include "qsgcurvestrokenode_p.h"
7#include "qsgcurveprocessor_p.h"
8#include "util/qquadpath_p.h"
9
10#include <QtGui/qrawfont.h>
11#include <QtGui/qpainterpath.h>
12
13QT_BEGIN_NAMESPACE
14
15QSGCurveGlyphAtlas::QSGCurveGlyphAtlas(const QRawFont &font)
16 : m_font(font)
17{
18 // The font size used for the curve atlas currently affects the outlines, since we don't
19 // really support cosmetic outlines. Therefore we need to pick one which gives large enough
20 // triangles relative to glyph size that we can reuse the same triangles for any font size.
21 // 64 is used as a "base font size" by the distance field renderer and other places in Qt
22 // because this also has the benefit it's big enough that hinting will be disabled.
23 static int curveGlyphAtlasFontSize = qEnvironmentVariableIntValue(varName: "QSGCURVEGLYPHATLAS_FONT_SIZE");
24 m_font.setPixelSize(curveGlyphAtlasFontSize > 0 ? qreal(curveGlyphAtlasFontSize) : 64.0);
25}
26
27QSGCurveGlyphAtlas::~QSGCurveGlyphAtlas()
28{
29}
30
31void QSGCurveGlyphAtlas::populate(const QList<glyph_t> &glyphs)
32{
33 for (glyph_t glyphIndex : glyphs) {
34 if (!m_glyphs.contains(key: glyphIndex)) {
35 QPainterPath path = m_font.pathForGlyph(glyphIndex);
36 QQuadPath quadPath = QQuadPath::fromPainterPath(path);
37 quadPath.setFillRule(Qt::WindingFill);
38
39 Glyph glyph;
40
41 QSGCurveProcessor::processStroke(strokePath: quadPath, miterLimit: 2, penWidth: 2, joinStyle: Qt::MiterJoin, capStyle: Qt::FlatCap,
42 addTriangle: [&glyph](const std::array<QVector2D, 3> &s,
43 const std::array<QVector2D, 3> &p,
44 const std::array<QVector2D, 3> &n,
45 bool isLine) {
46 glyph.strokeVertices.append(t: s.at(n: 0));
47 glyph.strokeVertices.append(t: s.at(n: 1));
48 glyph.strokeVertices.append(t: s.at(n: 2));
49
50 glyph.strokeUvs.append(t: p.at(n: 0));
51 glyph.strokeUvs.append(t: p.at(n: 1));
52 glyph.strokeUvs.append(t: p.at(n: 2));
53
54 glyph.strokeNormals.append(t: n.at(n: 0));
55 glyph.strokeNormals.append(t: n.at(n: 1));
56 glyph.strokeNormals.append(t: n.at(n: 2));
57
58 glyph.strokeElementIsLine.append(t: isLine);
59 });
60
61 quadPath = quadPath.subPathsClosed();
62 quadPath.addCurvatureData(); // ### Since the inside of glyphs is defined by order of
63 // vertices, this step could be simplified
64 QSGCurveProcessor::solveOverlaps(path&: quadPath);
65
66 QSGCurveProcessor::processFill(path: quadPath,
67 fillRule: Qt::WindingFill,
68 addTriangle: [&glyph](const std::array<QVector2D, 3> &v,
69 const std::array<QVector2D, 3> &n,
70 QSGCurveProcessor::uvForPointCallback uvForPoint)
71 {
72 glyph.vertices.append(t: v.at(n: 0));
73 glyph.vertices.append(t: v.at(n: 1));
74 glyph.vertices.append(t: v.at(n: 2));
75
76 QVector3D uv1 = uvForPoint(v.at(n: 0));
77 glyph.uvs.append(t: uv1);
78 glyph.uvs.append(t: uvForPoint(v.at(n: 1)));
79 glyph.uvs.append(t: uvForPoint(v.at(n: 2)));
80
81 glyph.normals.append(t: n.at(n: 0));
82 glyph.normals.append(t: n.at(n: 1));
83 glyph.normals.append(t: n.at(n: 2));
84
85 glyph.duvdx.append(t: QVector2D(uvForPoint(v.at(n: 0) + QVector2D(1, 0))) - QVector2D(uv1));
86 glyph.duvdy.append(t: QVector2D(uvForPoint(v.at(n: 0) + QVector2D(0, 1))) - QVector2D(uv1));
87 });
88
89 m_glyphs.insert(key: glyphIndex, value: glyph);
90 }
91 }
92}
93
94void QSGCurveGlyphAtlas::addStroke(QSGCurveStrokeNode *node,
95 glyph_t glyphIndex,
96 const QPointF &position) const
97{
98 const Glyph &glyph = m_glyphs[glyphIndex];
99
100 const QVector2D v(position);
101 for (qsizetype i = glyph.strokeElementIsLine.size() - 1; i >= 0; --i) {
102 QVector2D v1 = glyph.strokeVertices.at(i: i * 3 + 0) + v;
103 QVector2D v2 = glyph.strokeVertices.at(i: i * 3 + 1) + v;
104 QVector2D v3 = glyph.strokeVertices.at(i: i * 3 + 2) + v;
105 if (glyph.strokeElementIsLine.at(i)) {
106 node->appendTriangle(v: { v1, v2, v3 },
107 p: std::array<QVector2D, 2>({ glyph.strokeUvs.at(i: i * 3 + 0) + v, glyph.strokeUvs.at(i: i * 3 + 2) + v }),
108 n: { glyph.strokeNormals.at(i: i * 3 + 0), glyph.strokeNormals.at(i: i * 3 + 1), glyph.strokeNormals.at(i: i * 3 + 2) });
109 } else {
110 node->appendTriangle(v: { v1, v2, v3 },
111 p: { glyph.strokeUvs.at(i: i * 3 + 0) + v, glyph.strokeUvs.at(i: i * 3 + 1) + v, glyph.strokeUvs.at(i: i * 3 + 2) + v },
112 n: { glyph.strokeNormals.at(i: i * 3 + 0), glyph.strokeNormals.at(i: i * 3 + 1), glyph.strokeNormals.at(i: i * 3 + 2) });
113
114 }
115 }
116}
117
118void QSGCurveGlyphAtlas::addGlyph(QSGCurveFillNode *node,
119 glyph_t glyphIndex,
120 const QPointF &position,
121 qreal pixelSize) const
122{
123 const Glyph &glyph = m_glyphs[glyphIndex];
124
125 const float scaleFactor = pixelSize / m_font.pixelSize();
126 const QVector2D v(position);
127 for (qsizetype i = 0; i < glyph.vertices.size() / 3; ++i) {
128 node->appendTriangle(v1: scaleFactor * glyph.vertices.at(i: i * 3 + 0) + v,
129 v2: scaleFactor * glyph.vertices.at(i: i * 3 + 1) + v,
130 v3: scaleFactor * glyph.vertices.at(i: i * 3 + 2) + v,
131 uv1: glyph.uvs.at(i: i * 3 + 0),
132 uv2: glyph.uvs.at(i: i * 3 + 1),
133 uv3: glyph.uvs.at(i: i * 3 + 2),
134 n1: glyph.normals.at(i: i * 3 + 0),
135 n2: glyph.normals.at(i: i * 3 + 1),
136 n3: glyph.normals.at(i: i * 3 + 2),
137 duvdx: glyph.duvdx.at(i) / scaleFactor,
138 duvdy: glyph.duvdy.at(i) / scaleFactor);
139 }
140}
141
142QT_END_NAMESPACE
143

source code of qtdeclarative/src/quick/scenegraph/qsgcurveglyphatlas.cpp