# Texturing Workflow - Dubai Metaverse

## Overview

This document describes the texturing workflow from Substance Painter to Unreal Engine for the Dubai Metaverse project.

## Workflow Overview

1. **Model Preparation**: Prepare model with UVs
2. **Substance Painter**: Create textures
3. **Export**: Export texture sets
4. **Import to Unreal**: Import and create materials
5. **Assignment**: Assign materials to meshes

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## Model Preparation

### UV Mapping

- **UDIM Workflow**: Use UDIM for hero assets (8K textures)
- **Standard UVs**: Use standard UVs for primary/background assets
- **UV Layout**: Optimize UV layout for texture space
- **Seams**: Minimize visible seams

### Export for Texturing

- **Format**: FBX or OBJ
- **Include**: 
  - High-poly mesh (for baking)
  - Low-poly mesh (for texturing)
  - UVs
  - Material IDs (if using)

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## Substance Painter Workflow

### Project Setup

1. **Create Project**:
   - Import low-poly mesh
   - Import high-poly mesh (for baking)
   - Set texture resolution (8K for hero, 4K for primary)

2. **Bake Maps**:
   - Normal map (from high-poly)
   - Ambient Occlusion
   - Curvature
   - Position
   - Thickness

### Texture Creation

#### Base Color

- **Purpose**: Albedo/diffuse colors
- **Content**: Material colors, patterns, details
- **Notes**: No lighting information, pure color

#### Normal

- **Purpose**: Surface detail and geometry
- **Content**: Bumps, surface detail, geometry
- **Source**: Baked from high-poly or painted
- **Notes**: RGB format, tangent space

#### Roughness

- **Purpose**: Surface roughness (shininess)
- **Content**: 
  - Glass: 0.05-0.1 (very smooth)
  - Metal: 0.1-0.3 (smooth)
  - Concrete: 0.4-0.6 (rough)
- **Notes**: Critical for material realism

#### Metallic

- **Purpose**: Metallic vs. dielectric materials
- **Content**:
  - Metal: 1.0 (white)
  - Non-metal: 0.0 (black)
  - Mixed: Grayscale values
- **Notes**: Binary or grayscale

#### Ambient Occlusion

- **Purpose**: Shadow and occlusion information
- **Content**: Baked AO or painted
- **Notes**: Enhances depth and realism

#### Additional Maps (if needed)

- **Emissive**: For neon lights, interior lighting
- **Height**: For parallax/displacement (optional)
- **Opacity**: For transparency (glass)

### Export Settings

#### Resolution

- **Hero Assets**: 8K (8192x8192) per UDIM tile
- **Primary Buildings**: 4K (4096x4096)
- **Background**: 2K (2048x2048)

#### Format

- **Export**: PNG or TGA
- **Bit Depth**: 16-bit (recommended)
- **Color Space**: sRGB for base color, linear for others

#### Export Configuration

- **Base Color**: sRGB, 16-bit PNG
- **Normal**: Linear, 16-bit PNG
- **Roughness**: Linear, 16-bit PNG
- **Metallic**: Linear, 16-bit PNG
- **AO**: Linear, 16-bit PNG
- **Emissive**: sRGB, 16-bit PNG (if needed)

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## Import to Unreal Engine

### Texture Import

1. **Import Textures**:
   - Drag textures to Content Browser
   - Or use Import button

2. **Import Settings**:
   - **Compression**: 
     - Base Color: BC7 (DXT5)
     - Normal: BC5
     - Roughness/Metallic/AO: BC7
   - **sRGB**: 
     - Base Color: Enabled
     - Others: Disabled
   - **Mip Maps**: Generate mip maps
   - **Virtual Texturing**: Enable if using (optional)

### Material Creation

1. **Create Material**:
   - Create new material asset
   - Name: `M_AssetName_Type`

2. **Texture Assignment**:
   - Base Color: Connect Base Color texture
   - Normal: Connect Normal texture
   - Roughness: Connect Roughness texture
   - Metallic: Connect Metallic texture
   - Ambient Occlusion: Connect AO texture

3. **Material Settings**:
   - **Shading Model**: Default Lit
   - **Blend Mode**: Opaque (or Translucent for glass)
   - **Two-Sided**: Enable for glass if needed

4. **Parameters**:
   - Expose parameters for material instances
   - Color tint
   - Roughness multiplier
   - Metallic value

### Material Instances

1. **Create Instance**:
   - Right-click material > Create Material Instance
   - Name: `MI_AssetName_Variant`

2. **Adjust Parameters**:
   - Color variations
   - Roughness adjustments
   - Other exposed parameters

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## UDIM Workflow (Hero Assets)

### UDIM Overview

- **UDIM**: U-Dimension texture mapping
- **Tiles**: Multiple UV tiles (1001, 1002, 1003, etc.)
- **Usage**: Large assets requiring high-resolution textures

### Texture Naming

- **Format**: `T_AssetName_MapType_UDIMNumber`
- **Example**: 
  - `T_Hero_CayanTower_BaseColor_1001`
  - `T_Hero_CayanTower_BaseColor_1002`

### Import UDIM Textures

1. **Import All Tiles**: Import all UDIM tiles
2. **Create Material**: Create material with UDIM support
3. **Texture Arrays**: Use texture arrays or virtual textures
4. **UV Mapping**: Ensure UVs use UDIM coordinates

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## Quality Validation

### Texture Quality

- [ ] Resolution meets requirements
- [ ] No compression artifacts
- [ ] Colors are accurate
- [ ] Normal maps are correct
- [ ] Roughness values are realistic
- [ ] Metallic values are correct

### Material Quality

- [ ] Materials look realistic
- [ ] PBR workflow is correct
- [ ] Lighting responds correctly
- [ ] Performance is acceptable

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## Best Practices

### Texture Creation

1. **Reference**: Use real-world material references
2. **Consistency**: Maintain consistency across assets
3. **Detail**: Add appropriate detail level
4. **Optimization**: Balance quality and performance

### Material Creation

1. **Shared Materials**: Use shared materials where possible
2. **Instances**: Use material instances for variations
3. **Performance**: Optimize shader complexity
4. **Documentation**: Document material usage

### Workflow

1. **Iterate**: Iterate on textures based on feedback
2. **Test**: Test materials in level regularly
3. **Validate**: Validate quality and performance
4. **Document**: Document texture and material specifications

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## Troubleshooting

### Common Issues

**Issue**: Textures look washed out
- **Solution**: Check sRGB settings (base color should be sRGB)

**Issue**: Normal maps not working
- **Solution**: Check normal map format (BC5 compression)
- **Solution**: Verify normal map is tangent space

**Issue**: Materials too shiny/rough
- **Solution**: Adjust roughness values
- **Solution**: Check metallic values

**Issue**: Performance issues
- **Solution**: Reduce texture resolution
- **Solution**: Use texture streaming
- **Solution**: Optimize material complexity

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## Tools

### Primary Tools

- **Substance Painter**: Primary texturing tool
- **Substance Designer**: Procedural materials (optional)
- **Photoshop**: Additional editing (optional)

### Validation Tools

- **Unreal Material Editor**: Material validation
- **Performance Profiler**: Performance testing
- **Texture Validation Script**: `scripts/texture_validation.py`

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**Version**: 1.0
**Last Updated**: [Current Date]