# Reduction processor
By modifying the existing data in a GeometryData object, a lighter version of the geometry is created.
First it cleans up the geometry through welding, T-junction removal and double triangle removal. Then it re-links and removes triangles to decimate the triangle/vertex count, doing a very good job at preserving vertex/triangle-data, such as texture coordinates and geometry group IDs. It can re-calculate the normals of the modified geometry, and calculate texture coordinates for the geometry.
Finally it can create new diffuse, ambient, specular, displacement and normal maps based on the original geometry. Normal maps can be both world space and tangent space, and can be based either on the normals of the original geometry, or a normal map used by the original geometry.
# Reduction processor settings
Handles all the settings for Simplygon's simplification algorithms. The user can tell the reduction processor the relative importance of features using the Set{feature}Importance methods (or disabling an importance entirely by setting it to 0.0). The user may also specify to what extent the reducer is allowed to modify the vertex data from the original model when creating LODs, as well as other useful settings.
Following settings objects are available in reduction processor:
- Mapping image settings
- Bone reduction settings
- Visibility settings
- Repair settings
- Normal calculation settings
# Example
This example shows how to use the Reduction processor.
// 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.
bool importResult = sgSceneImporter->RunImport();
if (!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();
sgSceneExporter->SetExportFilePath(path);
sgSceneExporter->SetScene(sgScene);
// Run scene exporter.
bool exportResult = sgSceneExporter->RunExport();
if (!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.");
}
}
void RunReduction(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();
// Set reduction target to triangle ratio with a ratio of 50%.
sgReductionSettings->SetReductionTargets( Simplygon::EStopCondition::All, true, false, false, false );
sgReductionSettings->SetReductionTargetTriangleRatio( 0.5f );
// Start the reduction process.
printf("%s\n", "Start the reduction process.");
sgReductionProcessor->RunProcessing();
// 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);
}
RunReduction(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.
bool importResult = sgSceneImporter.RunImport();
if (!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();
sgSceneExporter.SetExportFilePath(path);
sgSceneExporter.SetScene(sgScene);
// Run scene exporter.
bool exportResult = sgSceneExporter.RunExport();
if (!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.");
}
}
static void RunReduction(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();
// Set reduction target to triangle ratio with a ratio of 50%.
sgReductionSettings.SetReductionTargets( Simplygon.EStopCondition.All, true, false, false, false );
sgReductionSettings.SetReductionTargetTriangleRatio( 0.5f );
// Start the reduction process.
Console.WriteLine("Start the reduction process.");
sgReductionProcessor.RunProcessing();
// 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;
}
RunReduction(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 simplygon import simplygon_loader
from simplygon import Simplygon
def LoadScene(sg: Simplygon.ISimplygon, path: str):
# Create scene importer
sgSceneImporter = sg.CreateSceneImporter()
sgSceneImporter.SetImportFilePath(path)
# Run scene importer.
importResult = sgSceneImporter.RunImport()
if not 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()
sgSceneExporter.SetExportFilePath(path)
sgSceneExporter.SetScene(sgScene)
# Run scene exporter.
exportResult = sgSceneExporter.RunExport()
if not 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.")
def RunReduction(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()
# Set reduction target to triangle ratio with a ratio of 50%.
sgReductionSettings.SetReductionTargets( Simplygon.EStopCondition_All, True, False, False, False )
sgReductionSettings.SetReductionTargetTriangleRatio( 0.5 )
# Start the reduction process.
print("Start the reduction process.")
sgReductionProcessor.RunProcessing()
# 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())
RunReduction(sg)
sg = None
gc.collect()