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
|
// Copyright (C) 2021 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "morphgeometry.h"
#include <qmath.h>
//! [vertex struct]
struct Vertex {
QVector3D position;
QVector3D normal;
QVector4D color;
};
//! [vertex struct]
//! [constructor]
MorphGeometry::MorphGeometry(QQuick3DObject *parent)
: QQuick3DGeometry(parent)
{
updateData();
}
//! [constructor]
//! [property]
void MorphGeometry::setGridSize(int gridSize)
{
if (m_gridSize == gridSize)
return;
m_gridSize = gridSize;
emit gridSizeChanged();
updateData();
update();
}
//! [property]
//! [updateData]
void MorphGeometry::updateData()
{
clear();
calculateGeometry();
addAttribute(QQuick3DGeometry::Attribute::PositionSemantic, 0,
QQuick3DGeometry::Attribute::ComponentType::F32Type);
addAttribute(QQuick3DGeometry::Attribute::NormalSemantic, 3 * sizeof(float),
QQuick3DGeometry::Attribute::ComponentType::F32Type);
addAttribute(QQuick3DGeometry::Attribute::ColorSemantic, 6 * sizeof(float),
QQuick3DGeometry::Attribute::ComponentType::F32Type);
addTargetAttribute(0, QQuick3DGeometry::Attribute::PositionSemantic, 0);
addTargetAttribute(0, QQuick3DGeometry::Attribute::NormalSemantic, m_targetPositions.size() * sizeof(float) * 3);
addTargetAttribute(0, QQuick3DGeometry::Attribute::ColorSemantic,
m_targetPositions.size() * sizeof(float) * 3 + m_targetNormals.size() * sizeof(float) * 3);
addAttribute(QQuick3DGeometry::Attribute::IndexSemantic, 0,
QQuick3DGeometry::Attribute::ComponentType::U32Type);
const int numVertexes = m_positions.size();
m_vertexBuffer.resize(numVertexes * sizeof(Vertex));
Vertex *vert = reinterpret_cast<Vertex *>(m_vertexBuffer.data());
for (int i = 0; i < numVertexes; ++i) {
Vertex &v = vert[i];
v.position = m_positions[i];
v.normal = m_normals[i];
v.color = m_colors[i];
}
m_targetBuffer.append(QByteArray(reinterpret_cast<char *>(m_targetPositions.data()), m_targetPositions.size() * sizeof(QVector3D)));
m_targetBuffer.append(QByteArray(reinterpret_cast<char *>(m_targetNormals.data()), m_targetNormals.size() * sizeof(QVector3D)));
m_targetBuffer.append(QByteArray(reinterpret_cast<char *>(m_targetColors.data()), m_targetColors.size() * sizeof(QVector4D)));
setStride(sizeof(Vertex));
setVertexData(m_vertexBuffer);
setTargetData(m_targetBuffer);
setPrimitiveType(QQuick3DGeometry::PrimitiveType::Triangles);
setBounds(boundsMin, boundsMax);
m_indexBuffer = QByteArray(reinterpret_cast<char *>(m_indexes.data()), m_indexes.size() * sizeof(quint32));
setIndexData(m_indexBuffer);
}
//! [updateData]
void MorphGeometry::calculateGeometry()
{
float dw = 10.0; // width/2
float dh = 10.0;
int iw = m_gridSize;
int ih = m_gridSize;
float wf = dw * 2 / iw; //factor grid coord => position
float hf = dh * 2 / ih;
m_positions.clear();
m_indexes.clear();
m_targetPositions.clear();
m_targetNormals.clear();
m_targetColors.clear();
constexpr float maxFloat = std::numeric_limits<float>::max();
boundsMin = QVector3D(maxFloat, maxFloat, maxFloat);
boundsMax = QVector3D(-maxFloat, -maxFloat, -maxFloat);
// We construct a rectangular grid of iw times ih vertices;
// ix and iy are indices into the grid. x, y, and z are the spatial
// coordinates we calculate for each vertex. tx, ty, and tz are the
// coordinates for the morph target.
for (int iy = 0; iy < ih; ++iy) {
for (int ix = 0; ix < iw; ++ix) {
float x = ix * wf - dw;
float z = iy * hf - dh;
// The base shape is a cosine wave, and the corresponding normal
// vectors are calculated from the partial derivatives.
float y = 2 * qCos(x) + 3.0;
QVector3D normal{2 * qSin(x), 2, 0};
float tx = x * 1.2;
float tz = z * 1.2;
constexpr float R = 16;
QVector3D targetPosition;
QVector3D targetNormal;
// The morph target shape is a hemisphere. Therefore we don't have
// to do complex math to calculate the normal vector, since all vectors
// from the center are normal to the surface of a sphere.
if (tx*tx + tz*tz < R*R) {
float ty = 0.4f * qSqrt(R*R - tx*tx - tz*tz);
targetPosition = {tx, ty, tz};
targetNormal = targetPosition;
} else {
targetPosition = {tx, -3, tz};
targetNormal = {0, 1, 0};
}
// Finally, we make the outside edges of the shapes vertical, so they look nicer.
if (ix == 0 || iy == 0 || ix == iw-1 || iy == ih-1) {
int iix = qMin(iw-2, qMax(1, ix));
int iiy = qMin(ih-2, qMax(1, iy));
x = iix * wf - dw;
z = iiy * hf - dh;
y = -3.0;
targetPosition.setY(-3);
}
if (iy >= ih-2)
normal = {0, 0, 1};
else if (iy <= 1)
normal = {0, 0, -1};
m_positions.append({x, y, z});
m_normals.append(normal.normalized());
m_targetPositions.append(targetPosition);
m_targetNormals.append(targetNormal.normalized());
// Set custom colors for the vertices:
const float tmp = (y + 5.0f) / 10.0f;
m_colors.append({1.0, tmp, tmp, 1.0f});
const float ttmp = (ix % (iw / 8)) < 3 ? 0.5 : 1.0;
m_targetColors.append({ttmp, ttmp, ttmp, 1.0f});
// Note: We only use the bounds of the target positions since they are strictly
// bigger than the original
boundsMin.setX(std::min(boundsMin.x(), targetPosition.x()));
boundsMin.setY(std::min(boundsMin.y(), targetPosition.y()));
boundsMin.setZ(std::min(boundsMin.z(), targetPosition.z()));
boundsMax.setX(std::max(boundsMax.x(), targetPosition.x()));
boundsMax.setY(std::max(boundsMax.y(), targetPosition.y()));
boundsMax.setZ(std::max(boundsMax.z(), targetPosition.z()));
}
}
for (int ix = 0; ix < iw - 1; ++ix) {
for (int iy = 0; iy < ih - 1; ++iy) {
int idx = ix + iy * ih;
m_indexes << idx << idx + iw << idx + iw + 1
<< idx << idx + iw + 1 << idx + 1;
}
}
}
|
