1/****************************************************************************
2**
3** Copyright (C) 2016 The Qt Company Ltd.
4** Contact: https://www.qt.io/licensing/
5**
6** This file is part of the demonstration applications of the Qt Toolkit.
7**
8** $QT_BEGIN_LICENSE:BSD$
9** Commercial License Usage
10** Licensees holding valid commercial Qt licenses may use this file in
11** accordance with the commercial license agreement provided with the
12** Software or, alternatively, in accordance with the terms contained in
13** a written agreement between you and The Qt Company. For licensing terms
14** and conditions see https://www.qt.io/terms-conditions. For further
15** information use the contact form at https://www.qt.io/contact-us.
16**
17** BSD License Usage
18** Alternatively, you may use this file under the terms of the BSD license
19** as follows:
20**
21** "Redistribution and use in source and binary forms, with or without
22** modification, are permitted provided that the following conditions are
23** met:
24** * Redistributions of source code must retain the above copyright
25** notice, this list of conditions and the following disclaimer.
26** * Redistributions in binary form must reproduce the above copyright
27** notice, this list of conditions and the following disclaimer in
28** the documentation and/or other materials provided with the
29** distribution.
30** * Neither the name of The Qt Company Ltd nor the names of its
31** contributors may be used to endorse or promote products derived
32** from this software without specific prior written permission.
33**
34**
35** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
36** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
37** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
38** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
39** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
41** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
42** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
43** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
44** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
45** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
46**
47** $QT_END_LICENSE$
48**
49****************************************************************************/
50
51#include "roundedbox.h"
52
53//============================================================================//
54// P3T2N3Vertex //
55//============================================================================//
56
57VertexDescription P3T2N3Vertex::description[] = {
58 {.field: VertexDescription::Position, GL_FLOAT, SIZE_OF_MEMBER(P3T2N3Vertex, position) / sizeof(float), .offset: 0, .index: 0},
59 {.field: VertexDescription::TexCoord, GL_FLOAT, SIZE_OF_MEMBER(P3T2N3Vertex, texCoord) / sizeof(float), .offset: sizeof(QVector3D), .index: 0},
60 {.field: VertexDescription::Normal, GL_FLOAT, SIZE_OF_MEMBER(P3T2N3Vertex, normal) / sizeof(float), .offset: sizeof(QVector3D) + sizeof(QVector2D), .index: 0},
61
62 {.field: VertexDescription::Null, .type: 0, .count: 0, .offset: 0, .index: 0},
63};
64
65//============================================================================//
66// GLRoundedBox //
67//============================================================================//
68
69float lerp(float a, float b, float t)
70{
71 return a * (1.0f - t) + b * t;
72}
73
74GLRoundedBox::GLRoundedBox(float r, float scale, int n)
75 : GLTriangleMesh<P3T2N3Vertex, unsigned short>((n+2)*(n+3)*4, (n+1)*(n+1)*24+36+72*(n+1))
76{
77 int vidx = 0, iidx = 0;
78 int vertexCountPerCorner = (n + 2) * (n + 3) / 2;
79
80 P3T2N3Vertex *vp = m_vb.lock();
81 unsigned short *ip = m_ib.lock();
82
83 if (!vp || !ip) {
84 qWarning(msg: "GLRoundedBox::GLRoundedBox: Failed to lock vertex buffer and/or index buffer.");
85 m_ib.unlock();
86 m_vb.unlock();
87 return;
88 }
89
90 for (int corner = 0; corner < 8; ++corner) {
91 QVector3D centre(corner & 1 ? 1.0f : -1.0f,
92 corner & 2 ? 1.0f : -1.0f,
93 corner & 4 ? 1.0f : -1.0f);
94 int winding = (corner & 1) ^ ((corner >> 1) & 1) ^ (corner >> 2);
95 int offsX = ((corner ^ 1) - corner) * vertexCountPerCorner;
96 int offsY = ((corner ^ 2) - corner) * vertexCountPerCorner;
97 int offsZ = ((corner ^ 4) - corner) * vertexCountPerCorner;
98
99 // Face polygons
100 if (winding) {
101 ip[iidx++] = vidx;
102 ip[iidx++] = vidx + offsX;
103 ip[iidx++] = vidx + offsY;
104
105 ip[iidx++] = vidx + vertexCountPerCorner - n - 2;
106 ip[iidx++] = vidx + vertexCountPerCorner - n - 2 + offsY;
107 ip[iidx++] = vidx + vertexCountPerCorner - n - 2 + offsZ;
108
109 ip[iidx++] = vidx + vertexCountPerCorner - 1;
110 ip[iidx++] = vidx + vertexCountPerCorner - 1 + offsZ;
111 ip[iidx++] = vidx + vertexCountPerCorner - 1 + offsX;
112 }
113
114 for (int i = 0; i < n + 2; ++i) {
115
116 // Edge polygons
117 if (winding && i < n + 1) {
118 ip[iidx++] = vidx + i + 1;
119 ip[iidx++] = vidx;
120 ip[iidx++] = vidx + offsY + i + 1;
121 ip[iidx++] = vidx + offsY;
122 ip[iidx++] = vidx + offsY + i + 1;
123 ip[iidx++] = vidx;
124
125 ip[iidx++] = vidx + i;
126 ip[iidx++] = vidx + 2 * i + 2;
127 ip[iidx++] = vidx + i + offsX;
128 ip[iidx++] = vidx + 2 * i + offsX + 2;
129 ip[iidx++] = vidx + i + offsX;
130 ip[iidx++] = vidx + 2 * i + 2;
131
132 ip[iidx++] = (corner + 1) * vertexCountPerCorner - 1 - i;
133 ip[iidx++] = (corner + 1) * vertexCountPerCorner - 2 - i;
134 ip[iidx++] = (corner + 1) * vertexCountPerCorner - 1 - i + offsZ;
135 ip[iidx++] = (corner + 1) * vertexCountPerCorner - 2 - i + offsZ;
136 ip[iidx++] = (corner + 1) * vertexCountPerCorner - 1 - i + offsZ;
137 ip[iidx++] = (corner + 1) * vertexCountPerCorner - 2 - i;
138 }
139
140 for (int j = 0; j <= i; ++j) {
141 QVector3D normal = QVector3D(i - j, j, n + 1 - i).normalized();
142 QVector3D offset(0.5f - r, 0.5f - r, 0.5f - r);
143 QVector3D pos = centre * (offset + r * normal);
144
145 vp[vidx].position = scale * pos;
146 vp[vidx].normal = centre * normal;
147 vp[vidx].texCoord = QVector2D(pos.x() + 0.5f, pos.y() + 0.5f);
148
149 // Corner polygons
150 if (i < n + 1) {
151 ip[iidx++] = vidx;
152 ip[iidx++] = vidx + i + 2 - winding;
153 ip[iidx++] = vidx + i + 1 + winding;
154 }
155 if (i < n) {
156 ip[iidx++] = vidx + i + 1 + winding;
157 ip[iidx++] = vidx + i + 2 - winding;
158 ip[iidx++] = vidx + 2 * i + 4;
159 }
160
161 ++vidx;
162 }
163 }
164
165 }
166
167 m_ib.unlock();
168 m_vb.unlock();
169}
170
171

source code of qtbase/examples/widgets/graphicsview/boxes/roundedbox.cpp