Material data

Materials contain color, intensity and multi-layered textures properties for the different channels. There are a number of different standard color channels and the user is also able to create custom user channels.

Materials in Simplygon support multi layered textures. Each channel in a Simplygon material can be composed of multiple texture layers having their own UV set. Multi layered textures for a channel are baked into a single texture while casting based on the blend function, see the casting with texture blend example.

MaterialTable

The MaterialTable is a collection of materials. The material table is assigned to an object. The material each part of the geometry is using is found in the array of material IDs received when calling GetMaterialIds from the geometry object.

Material

The Material class contains the material information. Materials are either imported alongside the object or created using the Simplygon API. They are identified by their name or index and the names are set with SetName. Channels for all commonly used PBR and non-PBR material models are pre-defined in Simplygon, and it is possible to add additional user-defined custom channels as well. The channels are defined using shading networks. If a shading network with texture nodes is used, a texture table must also be defined in order to successfully use any of the Simplygon material casters.

• AddUserChannel
  Creates user channels in the material.

• ShadingNetwork
  Set/get a shading network that will be used instead of the defined texture path or texture image in the relevant channel.

TextureTable

The TextureTable is a collection of textures. This structure is used by the material casters when casting based on input materials defined by shading networks. Each texture referenced by a texture node in the shading node networks that define the input materials must be represented in this table, which is supplied to the material casters along with the material table.

Texture

The Texture class contains definition of a single texture. The image data can either be defined using a single file path pointing to the input image, or by setting its ImageData object directly, using the format discussed in the Image Data section. When these are added to the texture table for usage in material casting with node networks, the name, as set by SetName(), is the identifier used to correlate a texture in the shading networks with a texture in the texture table. The Material Casting Example contains an example implementation of how to use this in a casting context properly.

Material casting

For information about casting materials see the Material Casters section.

Example

This example shows how to use the Reduction processor with material casting.

// Copyright (c) Microsoft Corporation. 
// Licensed under the MIT License. 

#include <string>
#include <stdlib.h>
#include <filesystem>
#include <future>
#include "SimplygonLoader.h"


Simplygon::spScene LoadScene(Simplygon::ISimplygon* sg, const char* path)
{
	// Create scene importer 
	Simplygon::spSceneImporter sgSceneImporter = sg->CreateSceneImporter();
	sgSceneImporter->SetImportFilePath(path);
	
	// Run scene importer. 
	auto importResult = sgSceneImporter->Run();
	if (Simplygon::Failed(importResult))
	{
		throw std::exception("Failed to load scene.");
	}
	Simplygon::spScene sgScene = sgSceneImporter->GetScene();
	return sgScene;
}

void SaveScene(Simplygon::ISimplygon* sg, Simplygon::spScene sgScene, const char* path)
{
	// Create scene exporter. 
	Simplygon::spSceneExporter sgSceneExporter = sg->CreateSceneExporter();
	std::string outputScenePath = std::string("output\\") + std::string("ReductionWithMaterialCasting") + std::string("_") + std::string(path);
	sgSceneExporter->SetExportFilePath(outputScenePath.c_str());
	sgSceneExporter->SetScene(sgScene);
	
	// Run scene exporter. 
	auto exportResult = sgSceneExporter->Run();
	if (Simplygon::Failed(exportResult))
	{
		throw std::exception("Failed to save scene.");
	}
}

void CheckLog(Simplygon::ISimplygon* sg)
{
	// Check if any errors occurred. 
	bool hasErrors = sg->ErrorOccurred();
	if (hasErrors)
	{
		Simplygon::spStringArray errors = sg->CreateStringArray();
		sg->GetErrorMessages(errors);
		auto errorCount = errors->GetItemCount();
		if (errorCount > 0)
		{
			printf("%s\n", "Errors:");
			for (auto errorIndex = 0U; errorIndex < errorCount; ++errorIndex)
			{
				Simplygon::spString errorString = errors->GetItem((int)errorIndex);
				printf("%s\n", errorString.c_str());
			}
			sg->ClearErrorMessages();
		}
	}
	else
	{
		printf("%s\n", "No errors.");
	}
	
	// Check if any warnings occurred. 
	bool hasWarnings = sg->WarningOccurred();
	if (hasWarnings)
	{
		Simplygon::spStringArray warnings = sg->CreateStringArray();
		sg->GetWarningMessages(warnings);
		auto warningCount = warnings->GetItemCount();
		if (warningCount > 0)
		{
			printf("%s\n", "Warnings:");
			for (auto warningIndex = 0U; warningIndex < warningCount; ++warningIndex)
			{
				Simplygon::spString warningString = warnings->GetItem((int)warningIndex);
				printf("%s\n", warningString.c_str());
			}
			sg->ClearWarningMessages();
		}
	}
	else
	{
		printf("%s\n", "No warnings.");
	}
	
	// Error out if Simplygon has errors. 
	if (hasErrors)
	{
		throw std::exception("Processing failed with an error");
	}
}

void RunReductionWithMaterialCasting(Simplygon::ISimplygon* sg)
{
	// Load scene to process. 	
	printf("%s\n", "Load scene to process.");
	Simplygon::spScene sgScene = LoadScene(sg, "../../../Assets/SimplygonMan/SimplygonMan.obj");
	
	// Create the reduction processor. 
	Simplygon::spReductionProcessor sgReductionProcessor = sg->CreateReductionProcessor();
	sgReductionProcessor->SetScene( sgScene );
	Simplygon::spReductionSettings sgReductionSettings = sgReductionProcessor->GetReductionSettings();
	Simplygon::spMappingImageSettings sgMappingImageSettings = sgReductionProcessor->GetMappingImageSettings();
	
	// Set reduction target to triangle ratio with a ratio of 50%. 
	sgReductionSettings->SetReductionTargets( Simplygon::EStopCondition::All, true, false, false, false );
	sgReductionSettings->SetReductionTargetTriangleRatio( 0.5f );
	
	// Generates a mapping image which is used after the reduction to cast new materials to the new 
	// reduced object. 
	sgMappingImageSettings->SetGenerateMappingImage( true );
	sgMappingImageSettings->SetApplyNewMaterialIds( true );
	sgMappingImageSettings->SetGenerateTangents( true );
	sgMappingImageSettings->SetUseFullRetexturing( true );
	sgMappingImageSettings->SetTexCoordGeneratorType( Simplygon::ETexcoordGeneratorType::ChartAggregator );
	Simplygon::spChartAggregatorSettings sgChartAggregatorSettings = sgMappingImageSettings->GetChartAggregatorSettings();
	
	// Enable the chart aggregator and reuse UV space. 
	sgChartAggregatorSettings->SetChartAggregatorMode( Simplygon::EChartAggregatorMode::SurfaceArea );
	sgChartAggregatorSettings->SetSeparateOverlappingCharts( false );
	Simplygon::spMappingImageOutputMaterialSettings sgOutputMaterialSettings = sgMappingImageSettings->GetOutputMaterialSettings(0);
	
	// Setting the size of the output material for the mapping image. This will be the output size of the 
	// textures when we do material casting in a later stage. 
	sgOutputMaterialSettings->SetTextureWidth( 2048 );
	sgOutputMaterialSettings->SetTextureHeight( 2048 );
	
	// Start the reduction process. 	
	printf("%s\n", "Start the reduction process.");
	sgReductionProcessor->RunProcessing();
	
	// Setup and run the diffuse material casting. 	
	printf("%s\n", "Setup and run the diffuse material casting.");
	Simplygon::spColorCaster sgDiffuseCaster = sg->CreateColorCaster();
	sgDiffuseCaster->SetMappingImage( sgReductionProcessor->GetMappingImage() );
	sgDiffuseCaster->SetSourceMaterials( sgScene->GetMaterialTable() );
	sgDiffuseCaster->SetSourceTextures( sgScene->GetTextureTable() );
	sgDiffuseCaster->SetOutputFilePath( "DiffuseTexture" );

	Simplygon::spColorCasterSettings sgDiffuseCasterSettings = sgDiffuseCaster->GetColorCasterSettings();
	sgDiffuseCasterSettings->SetMaterialChannel( "Diffuse" );
	sgDiffuseCasterSettings->SetOutputImageFileFormat( Simplygon::EImageOutputFormat::PNG );

	sgDiffuseCaster->RunProcessing();
	std::string diffuseTextureFilePath = sgDiffuseCaster->GetOutputFilePath().c_str();
	
	// Setup and run the normals material casting. 	
	printf("%s\n", "Setup and run the normals material casting.");
	Simplygon::spNormalCaster sgNormalsCaster = sg->CreateNormalCaster();
	sgNormalsCaster->SetMappingImage( sgReductionProcessor->GetMappingImage() );
	sgNormalsCaster->SetSourceMaterials( sgScene->GetMaterialTable() );
	sgNormalsCaster->SetSourceTextures( sgScene->GetTextureTable() );
	sgNormalsCaster->SetOutputFilePath( "NormalsTexture" );

	Simplygon::spNormalCasterSettings sgNormalsCasterSettings = sgNormalsCaster->GetNormalCasterSettings();
	sgNormalsCasterSettings->SetMaterialChannel( "Normals" );
	sgNormalsCasterSettings->SetGenerateTangentSpaceNormals( true );
	sgNormalsCasterSettings->SetOutputImageFileFormat( Simplygon::EImageOutputFormat::PNG );

	sgNormalsCaster->RunProcessing();
	std::string normalsTextureFilePath = sgNormalsCaster->GetOutputFilePath().c_str();
	
	// Update scene with new casted textures. 
	Simplygon::spMaterialTable sgMaterialTable = sg->CreateMaterialTable();
	Simplygon::spTextureTable sgTextureTable = sg->CreateTextureTable();
	Simplygon::spMaterial sgMaterial = sg->CreateMaterial();
	Simplygon::spTexture sgDiffuseTexture = sg->CreateTexture();
	sgDiffuseTexture->SetName( "Diffuse" );
	sgDiffuseTexture->SetFilePath( diffuseTextureFilePath.c_str() );
	sgTextureTable->AddTexture( sgDiffuseTexture );

	Simplygon::spShadingTextureNode sgDiffuseTextureShadingNode = sg->CreateShadingTextureNode();
	sgDiffuseTextureShadingNode->SetTexCoordLevel( 0 );
	sgDiffuseTextureShadingNode->SetTextureName( "Diffuse" );

	sgMaterial->AddMaterialChannel( "Diffuse" );
	sgMaterial->SetShadingNetwork( "Diffuse", sgDiffuseTextureShadingNode );
	Simplygon::spTexture sgNormalsTexture = sg->CreateTexture();
	sgNormalsTexture->SetName( "Normals" );
	sgNormalsTexture->SetFilePath( normalsTextureFilePath.c_str() );
	sgTextureTable->AddTexture( sgNormalsTexture );

	Simplygon::spShadingTextureNode sgNormalsTextureShadingNode = sg->CreateShadingTextureNode();
	sgNormalsTextureShadingNode->SetTexCoordLevel( 0 );
	sgNormalsTextureShadingNode->SetTextureName( "Normals" );

	sgMaterial->AddMaterialChannel( "Normals" );
	sgMaterial->SetShadingNetwork( "Normals", sgNormalsTextureShadingNode );

	sgMaterialTable->AddMaterial( sgMaterial );

	sgScene->GetTextureTable()->Clear();
	sgScene->GetMaterialTable()->Clear();
	sgScene->GetTextureTable()->Copy(sgTextureTable);
	sgScene->GetMaterialTable()->Copy(sgMaterialTable);
	
	// Save processed scene. 	
	printf("%s\n", "Save processed scene.");
	SaveScene(sg, sgScene, "Output.fbx");
	
	// Check log for any warnings or errors. 	
	printf("%s\n", "Check log for any warnings or errors.");
	CheckLog(sg);
}

int main()
{
	Simplygon::ISimplygon* sg = NULL;
	Simplygon::EErrorCodes initval = Simplygon::Initialize( &sg );
	if( initval != Simplygon::EErrorCodes::NoError )
	{
		printf( "Failed to initialize Simplygon: ErrorCode(%d)", (int)initval );
		return int(initval);
	}

	RunReductionWithMaterialCasting(sg);

	Simplygon::Deinitialize(sg);

	return 0;
}

// Copyright (c) Microsoft Corporation. 
// Licensed under the MIT License. 

using System;
using System.IO;
using System.Threading.Tasks;

public class Program
{
    static Simplygon.spScene LoadScene(Simplygon.ISimplygon sg, string path)
    {
        // Create scene importer 
        using Simplygon.spSceneImporter sgSceneImporter = sg.CreateSceneImporter();
        sgSceneImporter.SetImportFilePath(path);
        
        // Run scene importer. 
        var importResult = sgSceneImporter.Run();
        if (Simplygon.Simplygon.Failed(importResult))
        {
            throw new System.Exception("Failed to load scene.");
        }
        Simplygon.spScene sgScene = sgSceneImporter.GetScene();
        return sgScene;
    }

    static void SaveScene(Simplygon.ISimplygon sg, Simplygon.spScene sgScene, string path)
    {
        // Create scene exporter. 
        using Simplygon.spSceneExporter sgSceneExporter = sg.CreateSceneExporter();
        string outputScenePath = string.Join("", new string[] { "output\\", "ReductionWithMaterialCasting", "_", path });
        sgSceneExporter.SetExportFilePath(outputScenePath);
        sgSceneExporter.SetScene(sgScene);
        
        // Run scene exporter. 
        var exportResult = sgSceneExporter.Run();
        if (Simplygon.Simplygon.Failed(exportResult))
        {
            throw new System.Exception("Failed to save scene.");
        }
    }

    static void CheckLog(Simplygon.ISimplygon sg)
    {
        // Check if any errors occurred. 
        bool hasErrors = sg.ErrorOccurred();
        if (hasErrors)
        {
            Simplygon.spStringArray errors = sg.CreateStringArray();
            sg.GetErrorMessages(errors);
            var errorCount = errors.GetItemCount();
            if (errorCount > 0)
            {
                Console.WriteLine("Errors:");
                for (uint errorIndex = 0; errorIndex < errorCount; ++errorIndex)
                {
                    string errorString = errors.GetItem((int)errorIndex);
                    Console.WriteLine(errorString);
                }
                sg.ClearErrorMessages();
            }
        }
        else
        {
            Console.WriteLine("No errors.");
        }
        
        // Check if any warnings occurred. 
        bool hasWarnings = sg.WarningOccurred();
        if (hasWarnings)
        {
            Simplygon.spStringArray warnings = sg.CreateStringArray();
            sg.GetWarningMessages(warnings);
            var warningCount = warnings.GetItemCount();
            if (warningCount > 0)
            {
                Console.WriteLine("Warnings:");
                for (uint warningIndex = 0; warningIndex < warningCount; ++warningIndex)
                {
                    string warningString = warnings.GetItem((int)warningIndex);
                    Console.WriteLine(warningString);
                }
                sg.ClearWarningMessages();
            }
        }
        else
        {
            Console.WriteLine("No warnings.");
        }
        
        // Error out if Simplygon has errors. 
        if (hasErrors)
        {
            throw new System.Exception("Processing failed with an error");
        }
    }

    static void RunReductionWithMaterialCasting(Simplygon.ISimplygon sg)
    {
        // Load scene to process.         
        Console.WriteLine("Load scene to process.");
        Simplygon.spScene sgScene = LoadScene(sg, "../../../Assets/SimplygonMan/SimplygonMan.obj");
        
        // Create the reduction processor. 
        using Simplygon.spReductionProcessor sgReductionProcessor = sg.CreateReductionProcessor();
        sgReductionProcessor.SetScene( sgScene );
        using Simplygon.spReductionSettings sgReductionSettings = sgReductionProcessor.GetReductionSettings();
        using Simplygon.spMappingImageSettings sgMappingImageSettings = sgReductionProcessor.GetMappingImageSettings();
        
        // Set reduction target to triangle ratio with a ratio of 50%. 
        sgReductionSettings.SetReductionTargets( Simplygon.EStopCondition.All, true, false, false, false );
        sgReductionSettings.SetReductionTargetTriangleRatio( 0.5f );
        
        // Generates a mapping image which is used after the reduction to cast new materials to the new 
        // reduced object. 
        sgMappingImageSettings.SetGenerateMappingImage( true );
        sgMappingImageSettings.SetApplyNewMaterialIds( true );
        sgMappingImageSettings.SetGenerateTangents( true );
        sgMappingImageSettings.SetUseFullRetexturing( true );
        sgMappingImageSettings.SetTexCoordGeneratorType( Simplygon.ETexcoordGeneratorType.ChartAggregator );
        using Simplygon.spChartAggregatorSettings sgChartAggregatorSettings = sgMappingImageSettings.GetChartAggregatorSettings();
        
        // Enable the chart aggregator and reuse UV space. 
        sgChartAggregatorSettings.SetChartAggregatorMode( Simplygon.EChartAggregatorMode.SurfaceArea );
        sgChartAggregatorSettings.SetSeparateOverlappingCharts( false );
        using Simplygon.spMappingImageOutputMaterialSettings sgOutputMaterialSettings = sgMappingImageSettings.GetOutputMaterialSettings(0);
        
        // Setting the size of the output material for the mapping image. This will be the output size of the 
        // textures when we do material casting in a later stage. 
        sgOutputMaterialSettings.SetTextureWidth( 2048 );
        sgOutputMaterialSettings.SetTextureHeight( 2048 );
        
        // Start the reduction process.         
        Console.WriteLine("Start the reduction process.");
        sgReductionProcessor.RunProcessing();
        
        // Setup and run the diffuse material casting.         
        Console.WriteLine("Setup and run the diffuse material casting.");
        string diffuseTextureFilePath;
        using Simplygon.spColorCaster sgDiffuseCaster = sg.CreateColorCaster();
        sgDiffuseCaster.SetMappingImage( sgReductionProcessor.GetMappingImage() );
        sgDiffuseCaster.SetSourceMaterials( sgScene.GetMaterialTable() );
        sgDiffuseCaster.SetSourceTextures( sgScene.GetTextureTable() );
        sgDiffuseCaster.SetOutputFilePath( "DiffuseTexture" );

        using Simplygon.spColorCasterSettings sgDiffuseCasterSettings = sgDiffuseCaster.GetColorCasterSettings();
        sgDiffuseCasterSettings.SetMaterialChannel( "Diffuse" );
        sgDiffuseCasterSettings.SetOutputImageFileFormat( Simplygon.EImageOutputFormat.PNG );

        sgDiffuseCaster.RunProcessing();
        diffuseTextureFilePath = sgDiffuseCaster.GetOutputFilePath();
        
        // Setup and run the normals material casting.         
        Console.WriteLine("Setup and run the normals material casting.");
        string normalsTextureFilePath;
        using Simplygon.spNormalCaster sgNormalsCaster = sg.CreateNormalCaster();
        sgNormalsCaster.SetMappingImage( sgReductionProcessor.GetMappingImage() );
        sgNormalsCaster.SetSourceMaterials( sgScene.GetMaterialTable() );
        sgNormalsCaster.SetSourceTextures( sgScene.GetTextureTable() );
        sgNormalsCaster.SetOutputFilePath( "NormalsTexture" );

        using Simplygon.spNormalCasterSettings sgNormalsCasterSettings = sgNormalsCaster.GetNormalCasterSettings();
        sgNormalsCasterSettings.SetMaterialChannel( "Normals" );
        sgNormalsCasterSettings.SetGenerateTangentSpaceNormals( true );
        sgNormalsCasterSettings.SetOutputImageFileFormat( Simplygon.EImageOutputFormat.PNG );

        sgNormalsCaster.RunProcessing();
        normalsTextureFilePath = sgNormalsCaster.GetOutputFilePath();
        
        // Update scene with new casted textures. 
        using Simplygon.spMaterialTable sgMaterialTable = sg.CreateMaterialTable();
        using Simplygon.spTextureTable sgTextureTable = sg.CreateTextureTable();
        using Simplygon.spMaterial sgMaterial = sg.CreateMaterial();
        using Simplygon.spTexture sgDiffuseTexture = sg.CreateTexture();
        sgDiffuseTexture.SetName( "Diffuse" );
        sgDiffuseTexture.SetFilePath( diffuseTextureFilePath );
        sgTextureTable.AddTexture( sgDiffuseTexture );

        using Simplygon.spShadingTextureNode sgDiffuseTextureShadingNode = sg.CreateShadingTextureNode();
        sgDiffuseTextureShadingNode.SetTexCoordLevel( 0 );
        sgDiffuseTextureShadingNode.SetTextureName( "Diffuse" );

        sgMaterial.AddMaterialChannel( "Diffuse" );
        sgMaterial.SetShadingNetwork( "Diffuse", sgDiffuseTextureShadingNode );
        using Simplygon.spTexture sgNormalsTexture = sg.CreateTexture();
        sgNormalsTexture.SetName( "Normals" );
        sgNormalsTexture.SetFilePath( normalsTextureFilePath );
        sgTextureTable.AddTexture( sgNormalsTexture );

        using Simplygon.spShadingTextureNode sgNormalsTextureShadingNode = sg.CreateShadingTextureNode();
        sgNormalsTextureShadingNode.SetTexCoordLevel( 0 );
        sgNormalsTextureShadingNode.SetTextureName( "Normals" );

        sgMaterial.AddMaterialChannel( "Normals" );
        sgMaterial.SetShadingNetwork( "Normals", sgNormalsTextureShadingNode );

        sgMaterialTable.AddMaterial( sgMaterial );

        sgScene.GetTextureTable().Clear();
        sgScene.GetMaterialTable().Clear();
        sgScene.GetTextureTable().Copy(sgTextureTable);
        sgScene.GetMaterialTable().Copy(sgMaterialTable);
        
        // Save processed scene.         
        Console.WriteLine("Save processed scene.");
        SaveScene(sg, sgScene, "Output.fbx");
        
        // Check log for any warnings or errors.         
        Console.WriteLine("Check log for any warnings or errors.");
        CheckLog(sg);
    }

    static int Main(string[] args)
    {
        using var sg = Simplygon.Loader.InitSimplygon(out var errorCode, out var errorMessage);
        if (errorCode != Simplygon.EErrorCodes.NoError)
        {
            Console.WriteLine( $"Failed to initialize Simplygon: ErrorCode({(int)errorCode}) {errorMessage}" );
            return (int)errorCode;
        }
        RunReductionWithMaterialCasting(sg);

        return 0;
    }

}

# Copyright (c) Microsoft Corporation. 
# Licensed under the MIT License. 

import math
import os
import sys
import glob
import gc
import threading

from pathlib import Path
from simplygon10 import simplygon_loader
from simplygon10 import Simplygon


def LoadScene(sg: Simplygon.ISimplygon, path: str):
    # Create scene importer 
    sgSceneImporter = sg.CreateSceneImporter()
    sgSceneImporter.SetImportFilePath(path)
    
    # Run scene importer. 
    importResult = sgSceneImporter.Run()
    if Simplygon.Failed(importResult):
        raise Exception('Failed to load scene.')
    sgScene = sgSceneImporter.GetScene()
    return sgScene

def SaveScene(sg: Simplygon.ISimplygon, sgScene: Simplygon.spScene, path: str):
    # Create scene exporter. 
    sgSceneExporter = sg.CreateSceneExporter()
    outputScenePath = ''.join(['output\\', 'ReductionWithMaterialCasting', '_', path])
    sgSceneExporter.SetExportFilePath(outputScenePath)
    sgSceneExporter.SetScene(sgScene)
    
    # Run scene exporter. 
    exportResult = sgSceneExporter.Run()
    if Simplygon.Failed(exportResult):
        raise Exception('Failed to save scene.')

def CheckLog(sg: Simplygon.ISimplygon):
    # Check if any errors occurred. 
    hasErrors = sg.ErrorOccurred()
    if hasErrors:
        errors = sg.CreateStringArray()
        sg.GetErrorMessages(errors)
        errorCount = errors.GetItemCount()
        if errorCount > 0:
            print('Errors:')
            for errorIndex in range(errorCount):
                errorString = errors.GetItem(errorIndex)
                print(errorString)
            sg.ClearErrorMessages()
    else:
        print('No errors.')
    
    # Check if any warnings occurred. 
    hasWarnings = sg.WarningOccurred()
    if hasWarnings:
        warnings = sg.CreateStringArray()
        sg.GetWarningMessages(warnings)
        warningCount = warnings.GetItemCount()
        if warningCount > 0:
            print('Warnings:')
            for warningIndex in range(warningCount):
                warningString = warnings.GetItem(warningIndex)
                print(warningString)
            sg.ClearWarningMessages()
    else:
        print('No warnings.')
    
    # Error out if Simplygon has errors. 
    if hasErrors:
        raise Exception('Processing failed with an error')

def RunReductionWithMaterialCasting(sg: Simplygon.ISimplygon):
    # Load scene to process.     
    print("Load scene to process.")
    sgScene = LoadScene(sg, '../../../Assets/SimplygonMan/SimplygonMan.obj')
    
    # Create the reduction processor. 
    sgReductionProcessor = sg.CreateReductionProcessor()
    sgReductionProcessor.SetScene( sgScene )
    sgReductionSettings = sgReductionProcessor.GetReductionSettings()
    sgMappingImageSettings = sgReductionProcessor.GetMappingImageSettings()
    
    # Set reduction target to triangle ratio with a ratio of 50%. 
    sgReductionSettings.SetReductionTargets( Simplygon.EStopCondition_All, True, False, False, False )
    sgReductionSettings.SetReductionTargetTriangleRatio( 0.5 )
    
    # Generates a mapping image which is used after the reduction to cast new materials to the new 
    # reduced object. 
    sgMappingImageSettings.SetGenerateMappingImage( True )
    sgMappingImageSettings.SetApplyNewMaterialIds( True )
    sgMappingImageSettings.SetGenerateTangents( True )
    sgMappingImageSettings.SetUseFullRetexturing( True )
    sgMappingImageSettings.SetTexCoordGeneratorType( Simplygon.ETexcoordGeneratorType_ChartAggregator )
    sgChartAggregatorSettings = sgMappingImageSettings.GetChartAggregatorSettings()
    
    # Enable the chart aggregator and reuse UV space. 
    sgChartAggregatorSettings.SetChartAggregatorMode( Simplygon.EChartAggregatorMode_SurfaceArea )
    sgChartAggregatorSettings.SetSeparateOverlappingCharts( False )
    sgOutputMaterialSettings = sgMappingImageSettings.GetOutputMaterialSettings(0)
    
    # Setting the size of the output material for the mapping image. This will be the output size of the 
    # textures when we do material casting in a later stage. 
    sgOutputMaterialSettings.SetTextureWidth( 2048 )
    sgOutputMaterialSettings.SetTextureHeight( 2048 )
    
    # Start the reduction process.     
    print("Start the reduction process.")
    sgReductionProcessor.RunProcessing()
    
    # Setup and run the diffuse material casting.     
    print("Setup and run the diffuse material casting.")
    sgDiffuseCaster = sg.CreateColorCaster()
    sgDiffuseCaster.SetMappingImage( sgReductionProcessor.GetMappingImage() )
    sgDiffuseCaster.SetSourceMaterials( sgScene.GetMaterialTable() )
    sgDiffuseCaster.SetSourceTextures( sgScene.GetTextureTable() )
    sgDiffuseCaster.SetOutputFilePath( 'DiffuseTexture' )

    sgDiffuseCasterSettings = sgDiffuseCaster.GetColorCasterSettings()
    sgDiffuseCasterSettings.SetMaterialChannel( 'Diffuse' )
    sgDiffuseCasterSettings.SetOutputImageFileFormat( Simplygon.EImageOutputFormat_PNG )

    sgDiffuseCaster.RunProcessing()
    diffuseTextureFilePath = sgDiffuseCaster.GetOutputFilePath()
    
    # Setup and run the normals material casting.     
    print("Setup and run the normals material casting.")
    sgNormalsCaster = sg.CreateNormalCaster()
    sgNormalsCaster.SetMappingImage( sgReductionProcessor.GetMappingImage() )
    sgNormalsCaster.SetSourceMaterials( sgScene.GetMaterialTable() )
    sgNormalsCaster.SetSourceTextures( sgScene.GetTextureTable() )
    sgNormalsCaster.SetOutputFilePath( 'NormalsTexture' )

    sgNormalsCasterSettings = sgNormalsCaster.GetNormalCasterSettings()
    sgNormalsCasterSettings.SetMaterialChannel( 'Normals' )
    sgNormalsCasterSettings.SetGenerateTangentSpaceNormals( True )
    sgNormalsCasterSettings.SetOutputImageFileFormat( Simplygon.EImageOutputFormat_PNG )

    sgNormalsCaster.RunProcessing()
    normalsTextureFilePath = sgNormalsCaster.GetOutputFilePath()
    
    # Update scene with new casted textures. 
    sgMaterialTable = sg.CreateMaterialTable()
    sgTextureTable = sg.CreateTextureTable()
    sgMaterial = sg.CreateMaterial()
    sgDiffuseTexture = sg.CreateTexture()
    sgDiffuseTexture.SetName( 'Diffuse' )
    sgDiffuseTexture.SetFilePath( diffuseTextureFilePath )
    sgTextureTable.AddTexture( sgDiffuseTexture )

    sgDiffuseTextureShadingNode = sg.CreateShadingTextureNode()
    sgDiffuseTextureShadingNode.SetTexCoordLevel( 0 )
    sgDiffuseTextureShadingNode.SetTextureName( 'Diffuse' )

    sgMaterial.AddMaterialChannel( 'Diffuse' )
    sgMaterial.SetShadingNetwork( 'Diffuse', sgDiffuseTextureShadingNode )
    sgNormalsTexture = sg.CreateTexture()
    sgNormalsTexture.SetName( 'Normals' )
    sgNormalsTexture.SetFilePath( normalsTextureFilePath )
    sgTextureTable.AddTexture( sgNormalsTexture )

    sgNormalsTextureShadingNode = sg.CreateShadingTextureNode()
    sgNormalsTextureShadingNode.SetTexCoordLevel( 0 )
    sgNormalsTextureShadingNode.SetTextureName( 'Normals' )

    sgMaterial.AddMaterialChannel( 'Normals' )
    sgMaterial.SetShadingNetwork( 'Normals', sgNormalsTextureShadingNode )

    sgMaterialTable.AddMaterial( sgMaterial )

    sgScene.GetTextureTable().Clear()
    sgScene.GetMaterialTable().Clear()
    sgScene.GetTextureTable().Copy(sgTextureTable)
    sgScene.GetMaterialTable().Copy(sgMaterialTable)
    
    # Save processed scene.     
    print("Save processed scene.")
    SaveScene(sg, sgScene, 'Output.fbx')
    
    # Check log for any warnings or errors.     
    print("Check log for any warnings or errors.")
    CheckLog(sg)

if __name__ == '__main__':
        sg = simplygon_loader.init_simplygon()
        if sg is None:
            exit(Simplygon.GetLastInitializationError())

        RunReductionWithMaterialCasting(sg)

        sg = None
        gc.collect()