QGIS API Documentation 3.27.0-Master (75dc696944)
qgs3dexportobject.cpp
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1/***************************************************************************
2 Qgs3DExportObject.cpp
3 --------------------------------------
4 Date : June 2020
5 Copyright : (C) 2020 by Belgacem Nedjima
6 Email : gb underscore nedjima at esi dot dz
7 ***************************************************************************
8 * *
9 * This program is free software; you can redistribute it and/or modify *
10 * it under the terms of the GNU General Public License as published by *
11 * the Free Software Foundation; either version 2 of the License, or *
12 * (at your option) any later version. *
13 * *
14 ***************************************************************************/
15
16#include "qgs3dexportobject.h"
17
18#include <QVector3D>
19#include <QDir>
20#include <QImage>
21
22#include <Qt3DRender/QAttribute>
23#include <Qt3DRender/QBuffer>
24#include <Qt3DRender/QBufferDataGenerator>
25#include <Qt3DRender/QBufferDataGeneratorPtr>
26
27#include "qgslogger.h"
29
30
31template<typename T>
32void insertIndexData( QVector<uint> &vertexIndex, const QVector<T> &faceIndex )
33{
34 for ( int i = 0; i < faceIndex.size(); i += 3 )
35 {
36 if ( i + 2 >= faceIndex.size() ) continue;
37 // skip invalid triangles
38 if ( faceIndex[i] == faceIndex[i + 1] || faceIndex[i + 1] == faceIndex[i + 2] || faceIndex[i] == faceIndex[i + 2] )
39 continue;
40 for ( int j = 0; j < 3; ++j )
41 vertexIndex << faceIndex[i + j] + 1;
42 }
43}
44
45void Qgs3DExportObject::setupPositionCoordinates( const QVector<float> &positionsBuffer, float scale, const QVector3D &translation )
46{
47 for ( int i = 0; i < positionsBuffer.size(); i += 3 )
48 {
49 for ( int j = 0; j < 3; ++j )
50 {
51 mVertexPosition << positionsBuffer[i + j] * scale + translation[j];
52 }
53 }
54}
55
56void Qgs3DExportObject::setupFaces( const QVector<uint> &facesIndexes )
57{
58 insertIndexData<uint>( mIndexes, facesIndexes );
59}
60
61void Qgs3DExportObject::setupLine( const QVector<uint> &lineIndexes )
62{
63 Q_UNUSED( lineIndexes );
64 for ( int i = 0; i < mVertexPosition.size(); i += 3 ) mIndexes << i / 3 + 1;
65}
66
67void Qgs3DExportObject::setupNormalCoordinates( const QVector<float> &normalsBuffer )
68{
69 mNormals << normalsBuffer;
70}
71
72void Qgs3DExportObject::setupTextureCoordinates( const QVector<float> &texturesBuffer )
73{
74 mTexturesUV << texturesBuffer;
75}
76
78{
79 QMap<QString, QString> parameters = material->toExportParameters();
80 for ( auto it = parameters.begin(); it != parameters.end(); ++it )
81 {
82 setMaterialParameter( it.key(), it.value() );
83 }
84}
85
86void Qgs3DExportObject::objectBounds( float &minX, float &minY, float &minZ, float &maxX, float &maxY, float &maxZ )
87{
88 if ( mType != TriangularFaces ) return;
89 for ( const unsigned int vertice : mIndexes )
90 {
91 const int heightIndex = ( vertice - 1 ) * 3 + 1;
92 minX = std::min( minX, mVertexPosition[heightIndex - 1] );
93 maxX = std::max( maxX, mVertexPosition[heightIndex - 1] );
94 minY = std::min( minY, mVertexPosition[heightIndex] );
95 maxY = std::max( maxY, mVertexPosition[heightIndex] );
96 minZ = std::min( minZ, mVertexPosition[heightIndex + 1] );
97 maxZ = std::max( maxZ, mVertexPosition[heightIndex + 1] );
98 }
99}
100
101void Qgs3DExportObject::saveTo( QTextStream &out, float scale, const QVector3D &center )
102{
103 // Set groups
104 // turns out grouping doest work as expected in blender
105
106 // smoothen edges
107 if ( mSmoothEdges )
108 out << "s on\n";
109 else
110 out << "s off\n";
111
112 // Construct vertices
113 for ( int i = 0; i < mVertexPosition.size(); i += 3 )
114 {
115 // for now just ignore wrong vertex positions
116 out << "v ";
117 out << ( mVertexPosition[i] - center.x() ) / scale << " ";
118 out << ( mVertexPosition[i + 1] - center.y() ) / scale << " ";
119 out << ( mVertexPosition[i + 2] - center.z() ) / scale << "\n";
120 if ( i + 3 <= mNormals.size() )
121 {
122 out << "vn " << mNormals[i] << " " << mNormals[i + 1] << " " << mNormals[i + 2] << "\n";
123 }
124 const int u_index = i / 3 * 2;
125 if ( u_index + 1 < mTexturesUV.size() )
126 {
127 // TODO: flip texture in a more appropriate way (for repeated textures)
128 out << "vt " << mTexturesUV[u_index] << " " << 1.0f - mTexturesUV[u_index + 1] << "\n";
129 }
130 }
131
132 bool hasTextures = mTexturesUV.size() == mVertexPosition.size() / 3 * 2;
133 // if the object has normals then the normals and positions buffers should be the same size
134 bool hasNormals = mNormals.size() == mVertexPosition.size();
135
136 if ( !hasNormals && !mNormals.empty() )
137 {
138 QgsDebugMsg( "Vertex normals count and vertex positions count are different" );
139 }
140 int verticesCount = mVertexPosition.size() / 3;
141
142 auto getVertexIndex = [&]( int i ) -> QString
143 {
144 const int negativeIndex = -1 - ( verticesCount - i );
145 if ( hasNormals && !hasTextures )
146 return QStringLiteral( "%1//%2" ).arg( negativeIndex ).arg( negativeIndex );
147 if ( !hasNormals && hasTextures )
148 return QStringLiteral( "%1/%2" ).arg( negativeIndex ).arg( negativeIndex );
149 if ( hasNormals && hasTextures )
150 return QStringLiteral( "%1/%2/%3" ).arg( negativeIndex ).arg( negativeIndex ).arg( negativeIndex );
151 return QString::number( negativeIndex );
152 };
153
154 if ( mType == TriangularFaces )
155 {
156 // Construct triangular faces
157 for ( int i = 0; i < mIndexes.size(); i += 3 )
158 {
159 if ( mIndexes[i] == mIndexes[i + 1] && mIndexes[i + 1] == mIndexes[i + 2] )
160 continue;
161 out << "f " << getVertexIndex( mIndexes[i] );
162 out << " " << getVertexIndex( mIndexes[i + 1] );
163 out << " " << getVertexIndex( mIndexes[i + 2] );
164 out << "\n";
165 }
166 }
167 else if ( mType == LineStrip )
168 {
169 out << "l";
170 for ( const int i : mIndexes ) out << " " << getVertexIndex( i );
171 out << "\n";
172 }
173 else if ( mType == Points )
174 {
175 out << "p";
176 for ( int i = 0; i < mVertexPosition.size(); i += 3 )
177 out << " " << getVertexIndex( i / 3 + 1 );
178 out << "\n";
179 }
180}
181
182QString Qgs3DExportObject::saveMaterial( QTextStream &mtlOut, const QString &folderPath )
183{
184 QString materialName = mName + "_material";
185 if ( mMaterialParameters.size() == 0 && ( mTexturesUV.size() == 0 || mTextureImage.isNull() ) ) return QString();
186 mtlOut << "newmtl " << materialName << "\n";
187 if ( mTexturesUV.size() != 0 && !mTextureImage.isNull() )
188 {
189 const QString filePath = QDir( folderPath ).filePath( materialName + ".jpg" );
190 mTextureImage.save( filePath, "JPG" );
191 mtlOut << "\tmap_Kd " << materialName << ".jpg" << "\n";
192 }
193 for ( const QString &key : mMaterialParameters.keys() )
194 {
195 mtlOut << "\t" << key << " " << mMaterialParameters[key] << "\n";
196 }
197 mtlOut << "\tillum 2\n";
198 return materialName;
199}
void setMaterialParameter(const QString &parameter, const QString &value)
Sets a material parameter to be exported in the .mtl file.
void saveTo(QTextStream &out, float scale, const QVector3D &center)
Saves the current object to the output stream while scaling the object and centering it to be visible...
void objectBounds(float &minX, float &minY, float &minZ, float &maxX, float &maxY, float &maxZ)
Updates the box bounds explained with the current object bounds This expands the bounding box if the ...
void setupNormalCoordinates(const QVector< float > &normalsBuffer)
Sets normal coordinates for each vertex.
void setupPositionCoordinates(const QVector< float > &positionsBuffer, float scale=1.0f, const QVector3D &translation=QVector3D(0, 0, 0))
Sets positions coordinates and does the translation and scaling.
void setupMaterial(QgsAbstractMaterialSettings *material)
Sets the material parameters (diffuse color, shininess...) from phong material.
QString saveMaterial(QTextStream &mtlOut, const QString &folder)
saves the texture of the object and material information
void setupLine(const QVector< uint > &facesIndexes)
sets line vertex indexes
void setupFaces(const QVector< uint > &facesIndexes)
Sets the faces in facesIndexes to the faces in the object.
void setupTextureCoordinates(const QVector< float > &texturesBuffer)
Sets texture coordinates for each vertex.
virtual QMap< QString, QString > toExportParameters() const =0
Returns the parameters to be exported to .mtl file.
void insertIndexData(QVector< uint > &vertexIndex, const QVector< T > &faceIndex)
#define QgsDebugMsg(str)
Definition: qgslogger.h:38