Blender Script to export a 31x31 subdivided grid plane to a SL megaprim sculpty

mega-sculpty-exporter.py

import bpy
import numpy as np

bl_info = {
    "name": "Second Life Mega Sculpty Exporter",
    "blender": (4, 5, 0),
    "category": "Import-Export",
    "version": (1, 0, 0),
    "description": "Export 31x31 grid as a Second Life 1024x1024x256 megaprim sculpty PNG"
}

class EXPORT_OT_sculpty(bpy.types.Operator):
    bl_idname = "export_scene.sculpty"
    bl_label = "Export Sculpty"
    bl_options = {'REGISTER', 'UNDO'}
    
    filepath: bpy.props.StringProperty(subtype="FILE_PATH")
    
    def execute(self, context):
        obj = context.active_object
        
        if not obj or obj.type != 'MESH':
            self.report({'ERROR'}, "Select a mesh object")
            return {'CANCELLED'}
        
        mesh = obj.data
        if len(mesh.vertices) != 1024:
            self.report({'ERROR'}, "Mesh must have exactly 1024 vertices")
            return {'CANCELLED'}
        
        # Create Blender image (64x64)
        img = bpy.data.images.new("sculpty", width=64, height=64)
        
        # Prepare pixel data (RGBA format, 4 values per pixel)
        pixels = [0.0] * (64 * 64 * 4)
        
        # Map vertices to Second Life megaprim bounding box (1024x1024x256)
        for idx, vertex in enumerate(mesh.vertices):
            py = idx // 32
            px = idx % 32
            
            # Normalize to 0-1 range within megaprim bounds
            x_norm = (vertex.co.x + 512) / 1024  # X: -512 to +512
            y_norm = (vertex.co.y + 512) / 1024  # Y: -512 to +512
            z_norm = (vertex.co.z) / 256   # Z: 0 to +256
            
            # Clamp to 0-1 range
            x_norm = max(0, min(1, x_norm))
            y_norm = max(0, min(1, y_norm))
            z_norm = max(0, min(1, z_norm))
            
            # Map to 2x2 pixels in 64x64 image
            for dy in range(2):
                for dx in range(2):
                    pixel_y = py * 2 + dy
                    pixel_x = px * 2 + dx
                    pixel_idx = (pixel_y * 64 + pixel_x) * 4
                    pixels[pixel_idx] = x_norm      # R (X position)
                    pixels[pixel_idx + 1] = y_norm  # G (Y position)
                    pixels[pixel_idx + 2] = z_norm  # B (Z position)
                    pixels[pixel_idx + 3] = 1.0     # A (opacity)
        
        img.pixels[:] = pixels
        img.save_render(self.filepath)
        
        # Clean up
        bpy.data.images.remove(img)
        
        self.report({'INFO'}, f"Sculpty saved to {self.filepath}")
        return {'FINISHED'}
    
    def invoke(self, context, event):
        context.window_manager.fileselect_add(self)
        return {'RUNNING_MODAL'}

def menu_export(self, context):
    self.layout.operator(EXPORT_OT_sculpty.bl_idname, text="Second Life Mega Sculpty (.png)")

def register():
    bpy.utils.register_class(EXPORT_OT_sculpty)
    bpy.types.TOPBAR_MT_file_export.append(menu_export)

def unregister():
    bpy.utils.unregister_class(EXPORT_OT_sculpty)
    bpy.types.TOPBAR_MT_file_export.remove(menu_export)

if __name__ == "__main__":
    register()