stride3d/stride · error · InvalidOperationException

Invalid GeometricPrimitive

Error message

Invalid GeometricPrimitive [{0}]. Expecting a non-null Type

What it means

ProceduralModelDescriptor.GenerateModel requires its Type property (the IProceduralModel describing the primitive) to be set before generating into the target Model. A null Type throws InvalidOperationException; the descriptor has no primitive to build.

Solutions

1. Set descriptor.Type to a PrimitiveProceduralModelBase instance (e.g. new SphereProceduralModel()) before calling GenerateModel
2. Fix the asset serialization so Type is saved/loaded (re-save the descriptor asset)
3. Guard the call site by checking descriptor.Type != null before invoking GenerateModel

Example fix

// before
var descriptor = new ProceduralModelDescriptor();
descriptor.GenerateModel(services, model); // throws: Type is null
// after
var descriptor = new ProceduralModelDescriptor { Type = new SphereProceduralModel() };
descriptor.GenerateModel(services, model);

if (descriptor?.Type == null)
    throw new InvalidOperationException("ProceduralModelDescriptor.Type must be set before GenerateModel");
descriptor.GenerateModel(services, model);

static bool IsReady(ProceduralModelDescriptor d) => d?.Type != null;

try { descriptor.GenerateModel(services, model); }
catch (InvalidOperationException ex) when (ex.Message.Contains("non-null Type")) {
    descriptor.Type = new CubeProceduralModel(); // sensible default
    descriptor.GenerateModel(services, model);
}

When it happens

Trigger: Calling GenerateModel on a ProceduralModelDescriptor whose Type was never assigned (e.g. a descriptor created in code without setting Type), or a descriptor whose Type field was reset/deserialized as null.

Common situations: Building procedural models programmatically and forgetting to set descriptor.Type; assets saved by older versions where Type was not serialized; scene/model assets with partially configured primitive descriptors.

Related errors

• Cannot generate more than 65535 indices on feature level HW…
• Invalid GeometricPrimitive
• A texture with size [ ] already exist with the same output…
• Asked for " + i + " but no more than 10 default textures…
• Begin must be called before functionName

AI-assisted analysis of stride3d/stride@96fad776d2 (2026-09-14). Data as JSON: /api/errors/f473bbb5d5dfd8ee. Report an issue: GitHub.

Appendix: source

Thrown at sources/engine/Stride.Rendering/Rendering/ProceduralModels/ProceduralModelDescriptor.cs:59

        [DataMember(10)]
        [NotNull]
        [Display("Type", Expand = ExpandRule.Always)]
        public IProceduralModel Type { get; set; }

        public Model GenerateModel(IServiceRegistry services)
        {
            var model = new Model();
            GenerateModel(services, model);
            return model;
        }

        public void GenerateModel(IServiceRegistry services, Model model)
        {
            if (model == null) throw new ArgumentNullException(nameof(model));

            if (Type == null)
            {
                throw new InvalidOperationException("Invalid GeometricPrimitive [{0}]. Expecting a non-null Type");
            }

            Type.Generate(services, model);
        }
    }
}

View on GitHub (pinned to 96fad776d2)