qgsdiffusespecularmaterial: Add support for gl_ClipDistance

This is achieved with two changes:
1. define the plane equation as uniform with the
`Qgs3DUtils::addBoundingBoxParametersToEffect` call
2. include `clipplane.inc` file in the vertex shader file and call
setClipDistance()

With these changes, the planes defined in the framegraph are used.

src/3d/materials/qgsdiffusespecularmaterial.cpp

@@ -24,10 +24,11 @@
 #include <Qt3DRender/QTexture>
 
 #include "qgsdiffusespecularmaterial.h"
+#include "qgs3dmapsettings.h"
 #include "qgs3dutils.h"
 
 ///@cond PRIVATE
-QgsDiffuseSpecularMaterial::QgsDiffuseSpecularMaterial( QNode *parent )
+QgsDiffuseSpecularMaterial::QgsDiffuseSpecularMaterial( const Qgs3DMapSettings &mapSettings, QNode *parent )
   : QMaterial( parent )
   , mEffect( new Qt3DRender::QEffect() )
   , mAmbientParameter( new Qt3DRender::QParameter( QStringLiteral( "ka" ), QColor::fromRgbF( 0.05f, 0.05f, 0.05f, 1.0f ) ) )
@@ -40,13 +41,13 @@ QgsDiffuseSpecularMaterial::QgsDiffuseSpecularMaterial( QNode *parent )
   , mGL3Shader( new Qt3DRender::QShaderProgram( this ) )
   , mFilterKey( new Qt3DRender::QFilterKey( this ) )
 {
-  init();
+  init( mapSettings );
 }
 
 QgsDiffuseSpecularMaterial::~QgsDiffuseSpecularMaterial() = default;
 
 
-void QgsDiffuseSpecularMaterial::init()
+void QgsDiffuseSpecularMaterial::init( const Qgs3DMapSettings &mapSettings )
 {
   connect( mAmbientParameter, &Qt3DRender::QParameter::valueChanged,
            this, &QgsDiffuseSpecularMaterial::handleAmbientChanged );
@@ -61,6 +62,7 @@ void QgsDiffuseSpecularMaterial::init()
   mEffect->addParameter( mDiffuseParameter );
   mEffect->addParameter( mSpecularParameter );
   mEffect->addParameter( mShininessParameter );
+  Qgs3DUtils::addBoundingBoxParametersToEffect( mEffect, mapSettings );
 
   mGL3Shader->setVertexShaderCode( Qt3DRender::QShaderProgram::loadSource( QUrl( QStringLiteral( "qrc:/shaders/default.vert" ) ) ) );
 

src/3d/materials/qgsdiffusespecularmaterial.h

@@ -17,6 +17,7 @@
 #define QGSDIFFUSESPECULARMATERIAL_H
 
 #include "qgis_3d.h"
+#include "qgs3dmapsettings.h"
 
 #include <QColor>
 #include <QObject>
@@ -56,7 +57,7 @@ class _3D_EXPORT QgsDiffuseSpecularMaterial : public Qt3DRender::QMaterial
     /**
      * Constructor for QgsDiffuseSpecularMaterial, with the specified \a parent node.
      */
-    explicit QgsDiffuseSpecularMaterial( Qt3DCore::QNode *parent = nullptr );
+    explicit QgsDiffuseSpecularMaterial( const Qgs3DMapSettings &mapSettings, Qt3DCore::QNode *parent = nullptr );
     ~QgsDiffuseSpecularMaterial() override;
 
     QColor ambient() const;
@@ -77,7 +78,7 @@ class _3D_EXPORT QgsDiffuseSpecularMaterial : public Qt3DRender::QMaterial
     void shininessChanged( float shininess );
 
   private:
-    void init();
+    void init( const Qgs3DMapSettings &mapSettings );
 
     void handleAmbientChanged( const QVariant &var );
     void handleDiffuseChanged( const QVariant &var );

src/3d/terrain/qgsterraintileloader_p.cpp

@@ -64,7 +64,7 @@ void QgsTerrainTileLoader::createTextureComponent( QgsTerrainTileEntity *entity,
   {
     if ( isShadingEnabled )
     {
-      QgsDiffuseSpecularMaterial *diffuseMapMaterial = new QgsDiffuseSpecularMaterial;
+      QgsDiffuseSpecularMaterial *diffuseMapMaterial = new QgsDiffuseSpecularMaterial( mapSettings );
       diffuseMapMaterial->setDiffuse( QVariant::fromValue( texture ) );
       diffuseMapMaterial->setAmbient( shadingMaterial.ambient() );
       diffuseMapMaterial->setSpecular( shadingMaterial.specular() );
@@ -80,7 +80,7 @@ void QgsTerrainTileLoader::createTextureComponent( QgsTerrainTileEntity *entity,
   }
   else
   {
-    QgsDiffuseSpecularMaterial *diffuseMapMaterial  = new QgsDiffuseSpecularMaterial;
+    QgsDiffuseSpecularMaterial *diffuseMapMaterial  = new QgsDiffuseSpecularMaterial( mapSettings );
     diffuseMapMaterial->setDiffuse( shadingMaterial.diffuse() );
     diffuseMapMaterial->setAmbient( shadingMaterial.ambient() );
     diffuseMapMaterial->setSpecular( shadingMaterial.specular() );