2b75c156b6
Change-Id: I6441ff931dbd33b698d762e6f6784898f3f60fe7 Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
170 lines
6.7 KiB
C++
170 lines
6.7 KiB
C++
/****************************************************************************
|
|
**
|
|
** Copyright (C) 2015 The Qt Company Ltd.
|
|
** Contact: http://www.qt.io/licensing/
|
|
**
|
|
** This file is part of the QtCore module of the Qt Toolkit.
|
|
**
|
|
** $QT_BEGIN_LICENSE:BSD$
|
|
** You may use this file under the terms of the BSD license as follows:
|
|
**
|
|
** "Redistribution and use in source and binary forms, with or without
|
|
** modification, are permitted provided that the following conditions are
|
|
** met:
|
|
** * Redistributions of source code must retain the above copyright
|
|
** notice, this list of conditions and the following disclaimer.
|
|
** * Redistributions in binary form must reproduce the above copyright
|
|
** notice, this list of conditions and the following disclaimer in
|
|
** the documentation and/or other materials provided with the
|
|
** distribution.
|
|
** * Neither the name of The Qt Company Ltd nor the names of its
|
|
** contributors may be used to endorse or promote products derived
|
|
** from this software without specific prior written permission.
|
|
**
|
|
**
|
|
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
|
|
**
|
|
** $QT_END_LICENSE$
|
|
**
|
|
****************************************************************************/
|
|
|
|
#include "geometryengine.h"
|
|
|
|
#include <QVector2D>
|
|
#include <QVector3D>
|
|
|
|
struct VertexData
|
|
{
|
|
QVector3D position;
|
|
QVector2D texCoord;
|
|
};
|
|
|
|
//! [0]
|
|
GeometryEngine::GeometryEngine()
|
|
: indexBuf(QOpenGLBuffer::IndexBuffer)
|
|
{
|
|
initializeOpenGLFunctions();
|
|
|
|
// Generate 2 VBOs
|
|
arrayBuf.create();
|
|
indexBuf.create();
|
|
|
|
// Initializes cube geometry and transfers it to VBOs
|
|
initCubeGeometry();
|
|
}
|
|
|
|
GeometryEngine::~GeometryEngine()
|
|
{
|
|
arrayBuf.destroy();
|
|
indexBuf.destroy();
|
|
}
|
|
//! [0]
|
|
|
|
void GeometryEngine::initCubeGeometry()
|
|
{
|
|
// For cube we would need only 8 vertices but we have to
|
|
// duplicate vertex for each face because texture coordinate
|
|
// is different.
|
|
VertexData vertices[] = {
|
|
// Vertex data for face 0
|
|
{QVector3D(-1.0f, -1.0f, 1.0f), QVector2D(0.0f, 0.0f)}, // v0
|
|
{QVector3D( 1.0f, -1.0f, 1.0f), QVector2D(0.33f, 0.0f)}, // v1
|
|
{QVector3D(-1.0f, 1.0f, 1.0f), QVector2D(0.0f, 0.5f)}, // v2
|
|
{QVector3D( 1.0f, 1.0f, 1.0f), QVector2D(0.33f, 0.5f)}, // v3
|
|
|
|
// Vertex data for face 1
|
|
{QVector3D( 1.0f, -1.0f, 1.0f), QVector2D( 0.0f, 0.5f)}, // v4
|
|
{QVector3D( 1.0f, -1.0f, -1.0f), QVector2D(0.33f, 0.5f)}, // v5
|
|
{QVector3D( 1.0f, 1.0f, 1.0f), QVector2D(0.0f, 1.0f)}, // v6
|
|
{QVector3D( 1.0f, 1.0f, -1.0f), QVector2D(0.33f, 1.0f)}, // v7
|
|
|
|
// Vertex data for face 2
|
|
{QVector3D( 1.0f, -1.0f, -1.0f), QVector2D(0.66f, 0.5f)}, // v8
|
|
{QVector3D(-1.0f, -1.0f, -1.0f), QVector2D(1.0f, 0.5f)}, // v9
|
|
{QVector3D( 1.0f, 1.0f, -1.0f), QVector2D(0.66f, 1.0f)}, // v10
|
|
{QVector3D(-1.0f, 1.0f, -1.0f), QVector2D(1.0f, 1.0f)}, // v11
|
|
|
|
// Vertex data for face 3
|
|
{QVector3D(-1.0f, -1.0f, -1.0f), QVector2D(0.66f, 0.0f)}, // v12
|
|
{QVector3D(-1.0f, -1.0f, 1.0f), QVector2D(1.0f, 0.0f)}, // v13
|
|
{QVector3D(-1.0f, 1.0f, -1.0f), QVector2D(0.66f, 0.5f)}, // v14
|
|
{QVector3D(-1.0f, 1.0f, 1.0f), QVector2D(1.0f, 0.5f)}, // v15
|
|
|
|
// Vertex data for face 4
|
|
{QVector3D(-1.0f, -1.0f, -1.0f), QVector2D(0.33f, 0.0f)}, // v16
|
|
{QVector3D( 1.0f, -1.0f, -1.0f), QVector2D(0.66f, 0.0f)}, // v17
|
|
{QVector3D(-1.0f, -1.0f, 1.0f), QVector2D(0.33f, 0.5f)}, // v18
|
|
{QVector3D( 1.0f, -1.0f, 1.0f), QVector2D(0.66f, 0.5f)}, // v19
|
|
|
|
// Vertex data for face 5
|
|
{QVector3D(-1.0f, 1.0f, 1.0f), QVector2D(0.33f, 0.5f)}, // v20
|
|
{QVector3D( 1.0f, 1.0f, 1.0f), QVector2D(0.66f, 0.5f)}, // v21
|
|
{QVector3D(-1.0f, 1.0f, -1.0f), QVector2D(0.33f, 1.0f)}, // v22
|
|
{QVector3D( 1.0f, 1.0f, -1.0f), QVector2D(0.66f, 1.0f)} // v23
|
|
};
|
|
|
|
// Indices for drawing cube faces using triangle strips.
|
|
// Triangle strips can be connected by duplicating indices
|
|
// between the strips. If connecting strips have opposite
|
|
// vertex order then last index of the first strip and first
|
|
// index of the second strip needs to be duplicated. If
|
|
// connecting strips have same vertex order then only last
|
|
// index of the first strip needs to be duplicated.
|
|
GLushort indices[] = {
|
|
0, 1, 2, 3, 3, // Face 0 - triangle strip ( v0, v1, v2, v3)
|
|
4, 4, 5, 6, 7, 7, // Face 1 - triangle strip ( v4, v5, v6, v7)
|
|
8, 8, 9, 10, 11, 11, // Face 2 - triangle strip ( v8, v9, v10, v11)
|
|
12, 12, 13, 14, 15, 15, // Face 3 - triangle strip (v12, v13, v14, v15)
|
|
16, 16, 17, 18, 19, 19, // Face 4 - triangle strip (v16, v17, v18, v19)
|
|
20, 20, 21, 22, 23 // Face 5 - triangle strip (v20, v21, v22, v23)
|
|
};
|
|
|
|
//! [1]
|
|
// Transfer vertex data to VBO 0
|
|
arrayBuf.bind();
|
|
arrayBuf.allocate(vertices, 24 * sizeof(VertexData));
|
|
|
|
// Transfer index data to VBO 1
|
|
indexBuf.bind();
|
|
indexBuf.allocate(indices, 34 * sizeof(GLushort));
|
|
//! [1]
|
|
}
|
|
|
|
//! [2]
|
|
void GeometryEngine::drawCubeGeometry(QOpenGLShaderProgram *program)
|
|
{
|
|
// Tell OpenGL which VBOs to use
|
|
arrayBuf.bind();
|
|
indexBuf.bind();
|
|
|
|
// Offset for position
|
|
quintptr offset = 0;
|
|
|
|
// Tell OpenGL programmable pipeline how to locate vertex position data
|
|
int vertexLocation = program->attributeLocation("a_position");
|
|
program->enableAttributeArray(vertexLocation);
|
|
program->setAttributeBuffer(vertexLocation, GL_FLOAT, offset, 3, sizeof(VertexData));
|
|
|
|
// Offset for texture coordinate
|
|
offset += sizeof(QVector3D);
|
|
|
|
// Tell OpenGL programmable pipeline how to locate vertex texture coordinate data
|
|
int texcoordLocation = program->attributeLocation("a_texcoord");
|
|
program->enableAttributeArray(texcoordLocation);
|
|
program->setAttributeBuffer(texcoordLocation, GL_FLOAT, offset, 2, sizeof(VertexData));
|
|
|
|
// Draw cube geometry using indices from VBO 1
|
|
glDrawElements(GL_TRIANGLE_STRIP, 34, GL_UNSIGNED_SHORT, 0);
|
|
}
|
|
//! [2]
|