diff --git a/codegen/apipatcher.py b/codegen/apipatcher.py
index 8bb973f5..7958082a 100644
--- a/codegen/apipatcher.py
+++ b/codegen/apipatcher.py
@@ -454,7 +454,7 @@ def get_method_def(self, classname, methodname) -> str:
         # Get arg names and types
         idl_line = functions[name_idl]
         args = idl_line.split("(", 1)[1].split(")", 1)[0].split(",")
-        args = [Attribute(arg) for arg in args if arg.strip()]
+        args = [Attribute(arg, struct=False) for arg in args if arg.strip()]
         return_type = idl_line.split()[0]
         if return_type.startswith("[NewObject]"):
             # [NewObject] can be skipped: https://webidl.spec.whatwg.org/#NewObject
@@ -471,8 +471,10 @@ def get_method_def(self, classname, methodname) -> str:
         if len(args) == 1 and args[0].typename.endswith(
             ("Options", "Descriptor", "Configuration")
         ):
+            if not args[0].required:
+                args[0].typename = args[0].typename.removeprefix("optional ")
             assert args[0].typename.startswith("GPU")
-            des_is_optional = bool(args[0].default)
+            des_is_optional = bool(args[0].default)  # part of the logic above?
             attributes = self.idl.structs[args[0].typename[3:]].values()
             py_args = [
                 self._arg_from_attribute(methodname, attr, des_is_optional)
@@ -583,7 +585,7 @@ def get_method_comment(self, classname, methodname):
             idl_line = functions[name_idl]
 
             args = idl_line.split("(", 1)[1].split(")", 1)[0].split(",")
-            args = [Attribute(arg) for arg in args if arg.strip()]
+            args = [Attribute(arg, struct=False) for arg in args if arg.strip()]
 
             # If one arg that is a dict, flatten dict to kwargs
             if len(args) == 1 and args[0].typename.endswith(
diff --git a/codegen/idlparser.py b/codegen/idlparser.py
index dfbe6f00..5fb608ef 100644
--- a/codegen/idlparser.py
+++ b/codegen/idlparser.py
@@ -35,24 +35,33 @@ def get_idl_parser(*, allow_cache=True):
 class Attribute:
     """A little object to hold a function argument or struct field."""
 
-    def __init__(self, line):
+    def __init__(self, line: str, struct: bool = True):
         self.line = line.strip().strip(",;").strip()
 
         default = None  # None means 'no default' and "None" kinda means "auto".
-        required = False
+        required = False  # as opposed to optional, https://webidl.spec.whatwg.org/#required-dictionary-member but struct members?
+        # function args can be optional https://webidl.spec.whatwg.org/#dfn-optional-argument and a required if not
         arg = self.line
         if "=" in arg:
             arg, default = arg.rsplit("=", 1)
             arg, default = arg.strip(), default.strip()
         arg_type, arg_name = arg.strip().rsplit(" ", 1)
-        if arg_type.startswith("required "):
-            required = True
-            arg_type = arg_type.split(" ", 1)[1]
-            # required args should not have a default
-            assert default is None
-        elif arg_type.startswith("optional "):
-            arg_type = arg_type.split(" ", 1)[1]
-            default = default or "None"
+        if struct:
+            # some struct members might be required
+            if arg_type.startswith("required "):
+                required = True
+                arg_type = arg_type.split(" ", 1)[1]
+                # required args should not have a default
+                assert default is None
+        else:
+            # some function args might be optional
+            if arg_type.startswith("optional "):
+                required = False
+                arg_type = arg_type.split(" ", 1)[1]
+                default = default or "None"
+            else:
+                # but otherwise they are reuired
+                required = True
 
         if default:
             if default in ["false", "true"]:
@@ -66,7 +75,7 @@ def __init__(self, line):
     def __repr__(self):
         return f"<Attribute '{self.typename} {self.name}'>"
 
-    def to_str(self):
+    def to_str(self) -> str:
         return self.line
 
 
diff --git a/wgpu/_classes.py b/wgpu/_classes.py
index c14555ce..c1e6a502 100644
--- a/wgpu/_classes.py
+++ b/wgpu/_classes.py
@@ -1262,7 +1262,7 @@ def create_query_set(
 
     # IDL: undefined pushErrorScope(GPUErrorFilter filter);
     @apidiff.hide
-    def push_error_scope(self, filter: enums.ErrorFilterEnum | None = None) -> None:
+    def push_error_scope(self, filter: enums.ErrorFilterEnum) -> None:
         """Pushes a new GPU error scope onto the stack."""
         raise NotImplementedError()
 
@@ -1350,10 +1350,7 @@ def map_state(self) -> enums.BufferMapStateEnum:
 
     # IDL: Promise<undefined> mapAsync(GPUMapModeFlags mode, optional GPUSize64 offset = 0, optional GPUSize64 size);
     def map_sync(
-        self,
-        mode: flags.MapModeFlags | None = None,
-        offset: int = 0,
-        size: int | None = None,
+        self, mode: flags.MapModeFlags, offset: int = 0, size: int | None = None
     ) -> None:
         """Sync version of `map_async()`.
 
@@ -1364,10 +1361,7 @@ def map_sync(
 
     # IDL: Promise<undefined> mapAsync(GPUMapModeFlags mode, optional GPUSize64 offset = 0, optional GPUSize64 size);
     def map_async(
-        self,
-        mode: flags.MapModeFlags | None = None,
-        offset: int = 0,
-        size: int | None = None,
+        self, mode: flags.MapModeFlags, offset: int = 0, size: int | None = None
     ) -> GPUPromise[None]:
         """Maps the given range of the GPUBuffer.
 
@@ -1698,7 +1692,7 @@ class GPUPipelineBase:
     """A mixin class for render and compute pipelines."""
 
     # IDL: [NewObject] GPUBindGroupLayout getBindGroupLayout(unsigned long index);
-    def get_bind_group_layout(self, index: int | None = None) -> GPUBindGroupLayout:
+    def get_bind_group_layout(self, index: int) -> GPUBindGroupLayout:
         """Get the bind group layout at the given index."""
         raise NotImplementedError()
 
@@ -1772,7 +1766,7 @@ class GPUDebugCommandsMixin:
     """Mixin for classes that support debug groups and markers."""
 
     # IDL: undefined pushDebugGroup(USVString groupLabel);
-    def push_debug_group(self, group_label: str | None = None) -> None:
+    def push_debug_group(self, group_label: str) -> None:
         """Push a named debug group into the command stream."""
         raise NotImplementedError()
 
@@ -1782,7 +1776,7 @@ def pop_debug_group(self) -> None:
         raise NotImplementedError()
 
     # IDL: undefined insertDebugMarker(USVString markerLabel);
-    def insert_debug_marker(self, marker_label: str | None = None) -> None:
+    def insert_debug_marker(self, marker_label: str) -> None:
         """Insert the given message into the debug message queue."""
         raise NotImplementedError()
 
@@ -1791,7 +1785,7 @@ class GPURenderCommandsMixin:
     """Mixin for classes that provide rendering commands."""
 
     # IDL: undefined setPipeline(GPURenderPipeline pipeline);
-    def set_pipeline(self, pipeline: GPURenderPipeline | None = None) -> None:
+    def set_pipeline(self, pipeline: GPURenderPipeline) -> None:
         """Set the pipeline for this render pass.
 
         Arguments:
@@ -1802,8 +1796,8 @@ def set_pipeline(self, pipeline: GPURenderPipeline | None = None) -> None:
     # IDL: undefined setIndexBuffer(GPUBuffer buffer, GPUIndexFormat indexFormat, optional GPUSize64 offset = 0, optional GPUSize64 size);
     def set_index_buffer(
         self,
-        buffer: GPUBuffer | None = None,
-        index_format: enums.IndexFormatEnum | None = None,
+        buffer: GPUBuffer,
+        index_format: enums.IndexFormatEnum,
         offset: int = 0,
         size: int | None = None,
     ) -> None:
@@ -1822,11 +1816,7 @@ def set_index_buffer(
 
     # IDL: undefined setVertexBuffer(GPUIndex32 slot, GPUBuffer? buffer, optional GPUSize64 offset = 0, optional GPUSize64 size);
     def set_vertex_buffer(
-        self,
-        slot: int | None = None,
-        buffer: GPUBuffer | None = None,
-        offset: int = 0,
-        size: int | None = None,
+        self, slot: int, buffer: GPUBuffer, offset: int = 0, size: int | None = None
     ) -> None:
         """Associate a vertex buffer with a bind slot.
 
@@ -1844,7 +1834,7 @@ def set_vertex_buffer(
     # IDL: undefined draw(GPUSize32 vertexCount, optional GPUSize32 instanceCount = 1, optional GPUSize32 firstVertex = 0, optional GPUSize32 firstInstance = 0);
     def draw(
         self,
-        vertex_count: int | None = None,
+        vertex_count: int,
         instance_count: int = 1,
         first_vertex: int = 0,
         first_instance: int = 0,
@@ -1860,11 +1850,7 @@ def draw(
         raise NotImplementedError()
 
     # IDL: undefined drawIndirect(GPUBuffer indirectBuffer, GPUSize64 indirectOffset);
-    def draw_indirect(
-        self,
-        indirect_buffer: GPUBuffer | None = None,
-        indirect_offset: int | None = None,
-    ) -> None:
+    def draw_indirect(self, indirect_buffer: GPUBuffer, indirect_offset: int) -> None:
         """Like `draw()`, but the function arguments are in a buffer.
 
         Arguments:
@@ -1878,7 +1864,7 @@ def draw_indirect(
     # IDL: undefined drawIndexed(GPUSize32 indexCount, optional GPUSize32 instanceCount = 1, optional GPUSize32 firstIndex = 0, optional GPUSignedOffset32 baseVertex = 0, optional GPUSize32 firstInstance = 0);
     def draw_indexed(
         self,
-        index_count: int | None = None,
+        index_count: int,
         instance_count: int = 1,
         first_index: int = 0,
         base_vertex: int = 0,
@@ -1899,9 +1885,7 @@ def draw_indexed(
 
     # IDL: undefined drawIndexedIndirect(GPUBuffer indirectBuffer, GPUSize64 indirectOffset);
     def draw_indexed_indirect(
-        self,
-        indirect_buffer: GPUBuffer | None = None,
-        indirect_offset: int | None = None,
+        self, indirect_buffer: GPUBuffer, indirect_offset: int
     ) -> None:
         """
         Like `draw_indexed()`, but the function arguments are in a buffer.
@@ -1961,7 +1945,7 @@ def begin_render_pass(
 
     # IDL: undefined clearBuffer( GPUBuffer buffer, optional GPUSize64 offset = 0, optional GPUSize64 size);
     def clear_buffer(
-        self, buffer: GPUBuffer | None = None, offset: int = 0, size: int | None = None
+        self, buffer: GPUBuffer, offset: int = 0, size: int | None = None
     ) -> None:
         """Set (part of) the given buffer to zeros.
 
@@ -1977,10 +1961,10 @@ def clear_buffer(
     # IDL: undefined copyBufferToBuffer( GPUBuffer source, GPUSize64 sourceOffset, GPUBuffer destination, GPUSize64 destinationOffset, optional GPUSize64 size);
     def copy_buffer_to_buffer(
         self,
-        source: GPUBuffer | None = None,
-        source_offset: int | None = None,
-        destination: GPUBuffer | None = None,
-        destination_offset: int | None = None,
+        source: GPUBuffer,
+        source_offset: int,
+        destination: GPUBuffer,
+        destination_offset: int,
         size: int | None = None,
     ) -> None:
         """Copy the contents of a buffer to another buffer.
@@ -1999,9 +1983,9 @@ def copy_buffer_to_buffer(
     # IDL: undefined copyBufferToTexture( GPUTexelCopyBufferInfo source, GPUTexelCopyTextureInfo destination, GPUExtent3D copySize);
     def copy_buffer_to_texture(
         self,
-        source: structs.TexelCopyBufferInfoStruct | None = None,
-        destination: structs.TexelCopyTextureInfoStruct | None = None,
-        copy_size: tuple[int, int, int] | structs.Extent3DStruct | None = None,
+        source: structs.TexelCopyBufferInfoStruct,
+        destination: structs.TexelCopyTextureInfoStruct,
+        copy_size: tuple[int, int, int] | structs.Extent3DStruct,
     ) -> None:
         """Copy the contents of a buffer to a texture (view).
 
@@ -2017,9 +2001,9 @@ def copy_buffer_to_texture(
     # IDL: undefined copyTextureToBuffer( GPUTexelCopyTextureInfo source, GPUTexelCopyBufferInfo destination, GPUExtent3D copySize);
     def copy_texture_to_buffer(
         self,
-        source: structs.TexelCopyTextureInfoStruct | None = None,
-        destination: structs.TexelCopyBufferInfoStruct | None = None,
-        copy_size: tuple[int, int, int] | structs.Extent3DStruct | None = None,
+        source: structs.TexelCopyTextureInfoStruct,
+        destination: structs.TexelCopyBufferInfoStruct,
+        copy_size: tuple[int, int, int] | structs.Extent3DStruct,
     ) -> None:
         """Copy the contents of a texture (view) to a buffer.
 
@@ -2035,9 +2019,9 @@ def copy_texture_to_buffer(
     # IDL: undefined copyTextureToTexture( GPUTexelCopyTextureInfo source, GPUTexelCopyTextureInfo destination, GPUExtent3D copySize);
     def copy_texture_to_texture(
         self,
-        source: structs.TexelCopyTextureInfoStruct | None = None,
-        destination: structs.TexelCopyTextureInfoStruct | None = None,
-        copy_size: tuple[int, int, int] | structs.Extent3DStruct | None = None,
+        source: structs.TexelCopyTextureInfoStruct,
+        destination: structs.TexelCopyTextureInfoStruct,
+        copy_size: tuple[int, int, int] | structs.Extent3DStruct,
     ) -> None:
         """Copy the contents of a texture (view) to another texture (view).
 
@@ -2060,11 +2044,11 @@ def finish(self, *, label: str = "") -> GPUCommandBuffer:
     # IDL: undefined resolveQuerySet( GPUQuerySet querySet, GPUSize32 firstQuery, GPUSize32 queryCount, GPUBuffer destination, GPUSize64 destinationOffset);
     def resolve_query_set(
         self,
-        query_set: GPUQuerySet | None = None,
-        first_query: int | None = None,
-        query_count: int | None = None,
-        destination: GPUBuffer | None = None,
-        destination_offset: int | None = None,
+        query_set: GPUQuerySet,
+        first_query: int,
+        query_count: int,
+        destination: GPUBuffer,
+        destination_offset: int,
     ) -> None:
         """
         Resolves query results from a ``GPUQuerySet`` out into a range of a ``GPUBuffer``.
@@ -2090,7 +2074,7 @@ class GPUComputePassEncoder(
     """
 
     # IDL: undefined setPipeline(GPUComputePipeline pipeline);
-    def set_pipeline(self, pipeline: GPUComputePipeline | None = None) -> None:
+    def set_pipeline(self, pipeline: GPUComputePipeline) -> None:
         """Set the pipeline for this compute pass.
 
         Arguments:
@@ -2101,7 +2085,7 @@ def set_pipeline(self, pipeline: GPUComputePipeline | None = None) -> None:
     # IDL: undefined dispatchWorkgroups(GPUSize32 workgroupCountX, optional GPUSize32 workgroupCountY = 1, optional GPUSize32 workgroupCountZ = 1);
     def dispatch_workgroups(
         self,
-        workgroup_count_x: int | None = None,
+        workgroup_count_x: int,
         workgroup_count_y: int = 1,
         workgroup_count_z: int = 1,
     ) -> None:
@@ -2116,9 +2100,7 @@ def dispatch_workgroups(
 
     # IDL: undefined dispatchWorkgroupsIndirect(GPUBuffer indirectBuffer, GPUSize64 indirectOffset);
     def dispatch_workgroups_indirect(
-        self,
-        indirect_buffer: GPUBuffer | None = None,
-        indirect_offset: int | None = None,
+        self, indirect_buffer: GPUBuffer, indirect_offset: int
     ) -> None:
         """Like `dispatch_workgroups()`, but the function arguments are in a buffer.
 
@@ -2149,12 +2131,12 @@ class GPURenderPassEncoder(
     # IDL: undefined setViewport(float x, float y, float width, float height, float minDepth, float maxDepth);
     def set_viewport(
         self,
-        x: float | None = None,
-        y: float | None = None,
-        width: float | None = None,
-        height: float | None = None,
-        min_depth: float | None = None,
-        max_depth: float | None = None,
+        x: float,
+        y: float,
+        width: float,
+        height: float,
+        min_depth: float,
+        max_depth: float,
     ) -> None:
         """Set the viewport for this render pass. The whole scene is rendered
         to this sub-rectangle.
@@ -2171,13 +2153,7 @@ def set_viewport(
         raise NotImplementedError()
 
     # IDL: undefined setScissorRect(GPUIntegerCoordinate x, GPUIntegerCoordinate y,  GPUIntegerCoordinate width, GPUIntegerCoordinate height);
-    def set_scissor_rect(
-        self,
-        x: int | None = None,
-        y: int | None = None,
-        width: int | None = None,
-        height: int | None = None,
-    ) -> None:
+    def set_scissor_rect(self, x: int, y: int, width: int, height: int) -> None:
         """Set the scissor rectangle for this render pass. The scene
         is rendered as usual, but is only applied to this sub-rectangle.
 
@@ -2191,8 +2167,7 @@ def set_scissor_rect(
 
     # IDL: undefined setBlendConstant(GPUColor color);
     def set_blend_constant(
-        self,
-        color: tuple[float, float, float, float] | structs.ColorStruct | None = None,
+        self, color: tuple[float, float, float, float] | structs.ColorStruct
     ) -> None:
         """Set the blend color for the render pass.
 
@@ -2202,7 +2177,7 @@ def set_blend_constant(
         raise NotImplementedError()
 
     # IDL: undefined setStencilReference(GPUStencilValue reference);
-    def set_stencil_reference(self, reference: int | None = None) -> None:
+    def set_stencil_reference(self, reference: int) -> None:
         """Set the reference stencil value for this render pass.
 
         Arguments:
@@ -2211,7 +2186,7 @@ def set_stencil_reference(self, reference: int | None = None) -> None:
         raise NotImplementedError()
 
     # IDL: undefined executeBundles(sequence<GPURenderBundle> bundles);
-    def execute_bundles(self, bundles: Sequence[GPURenderBundle] | None = None) -> None:
+    def execute_bundles(self, bundles: Sequence[GPURenderBundle]) -> None:
         """Executes commands previously recorded into the render bundles
           as part of this render pass.
 
@@ -2226,7 +2201,7 @@ def end(self) -> None:
         raise NotImplementedError()
 
     # IDL: undefined beginOcclusionQuery(GPUSize32 queryIndex);
-    def begin_occlusion_query(self, query_index: int | None = None) -> None:
+    def begin_occlusion_query(self, query_index: int) -> None:
         """Begins an occlusion query.
 
         Arguments:
@@ -2275,7 +2250,7 @@ class GPUQueue(GPUObjectBase):
     """
 
     # IDL: undefined submit(sequence<GPUCommandBuffer> commandBuffers);
-    def submit(self, command_buffers: Sequence[GPUCommandBuffer] | None = None) -> None:
+    def submit(self, command_buffers: Sequence[GPUCommandBuffer]) -> None:
         """Submit a `GPUCommandBuffer` to the queue.
 
         Arguments:
@@ -2286,9 +2261,9 @@ def submit(self, command_buffers: Sequence[GPUCommandBuffer] | None = None) -> N
     # IDL: undefined writeBuffer( GPUBuffer buffer, GPUSize64 bufferOffset, AllowSharedBufferSource data, optional GPUSize64 dataOffset = 0, optional GPUSize64 size);
     def write_buffer(
         self,
-        buffer: GPUBuffer | None = None,
-        buffer_offset: int | None = None,
-        data: ArrayLike | None = None,
+        buffer: GPUBuffer,
+        buffer_offset: int,
+        data: ArrayLike,
         data_offset: int = 0,
         size: int | None = None,
     ) -> None:
@@ -2338,10 +2313,10 @@ def read_buffer(
     # IDL: undefined writeTexture( GPUTexelCopyTextureInfo destination, AllowSharedBufferSource data, GPUTexelCopyBufferLayout dataLayout, GPUExtent3D size);
     def write_texture(
         self,
-        destination: structs.TexelCopyTextureInfoStruct | None = None,
-        data: ArrayLike | None = None,
-        data_layout: structs.TexelCopyBufferLayoutStruct | None = None,
-        size: tuple[int, int, int] | structs.Extent3DStruct | None = None,
+        destination: structs.TexelCopyTextureInfoStruct,
+        data: ArrayLike,
+        data_layout: structs.TexelCopyBufferLayoutStruct,
+        size: tuple[int, int, int] | structs.Extent3DStruct,
     ) -> None:
         """Takes the data contents and schedules a write operation of
         these contents to the destination texture in the queue. A
@@ -2388,9 +2363,9 @@ def read_texture(
     @apidiff.hide("Specific to browsers")
     def copy_external_image_to_texture(
         self,
-        source: structs.CopyExternalImageSourceInfoStruct | None = None,
-        destination: structs.CopyExternalImageDestInfoStruct | None = None,
-        copy_size: tuple[int, int, int] | structs.Extent3DStruct | None = None,
+        source: structs.CopyExternalImageSourceInfoStruct,
+        destination: structs.CopyExternalImageDestInfoStruct,
+        copy_size: tuple[int, int, int] | structs.Extent3DStruct,
     ) -> None:
         raise NotImplementedError()
 
@@ -2451,7 +2426,7 @@ class GPUOutOfMemoryError(GPUError, MemoryError):
     """An error raised when the GPU is out of memory."""
 
     # IDL: constructor(DOMString message);
-    def __init__(self, message: str | None = None):
+    def __init__(self, message: str):
         super().__init__(message or "GPU is out of memory.")
 
 
@@ -2459,7 +2434,7 @@ class GPUValidationError(GPUError):
     """An error raised when the pipeline could not be validated."""
 
     # IDL: constructor(DOMString message);
-    def __init__(self, message: str | None = None):
+    def __init__(self, message: str):
         super().__init__(message)
 
 
@@ -2467,9 +2442,7 @@ class GPUPipelineError(Exception):
     """An error raised when a pipeline could not be created."""
 
     # IDL: constructor(optional DOMString message = "", GPUPipelineErrorInit options);
-    def __init__(
-        self, message: str = "", options: structs.PipelineErrorInitStruct | None = None
-    ):
+    def __init__(self, message: str, options: structs.PipelineErrorInitStruct):
         super().__init__(message or "")
         self._options = options
 
@@ -2488,7 +2461,7 @@ class GPUInternalError(GPUError):
     """
 
     # IDL: constructor(DOMString message);
-    def __init__(self, message: str | None = None):
+    def __init__(self, message: str):
         super().__init__(message)
 
 
diff --git a/wgpu/backends/wgpu_native/_api.py b/wgpu/backends/wgpu_native/_api.py
index 725c5f33..c96ff973 100644
--- a/wgpu/backends/wgpu_native/_api.py
+++ b/wgpu/backends/wgpu_native/_api.py
@@ -2528,10 +2528,7 @@ def _check_range(self, offset, size):
         return offset, size
 
     def map_async(
-        self,
-        mode: flags.MapModeFlags | None = None,
-        offset: int = 0,
-        size: int | None = None,
+        self, mode: flags.MapModeFlags, offset: int = 0, size: int | None = None
     ) -> GPUPromise[None]:
         sync_on_read = True
 
@@ -2867,7 +2864,7 @@ def get_compilation_info_async(self) -> GPUPromise[GPUCompilationInfo]:
 
 
 class GPUPipelineBase(classes.GPUPipelineBase):
-    def get_bind_group_layout(self, index: int | None = None) -> GPUBindGroupLayout:
+    def get_bind_group_layout(self, index: int) -> GPUBindGroupLayout:
         # H: WGPUBindGroupLayout wgpuComputePipelineGetBindGroupLayout(WGPUComputePipeline computePipeline, uint32_t groupIndex)
         # H: WGPUBindGroupLayout wgpuRenderPipelineGetBindGroupLayout(WGPURenderPipeline renderPipeline, uint32_t groupIndex)
         function = type(self)._get_bind_group_layout_function
@@ -3000,7 +2997,7 @@ def _not_implemented(self, name) -> NoReturn:
 
 class GPUDebugCommandsMixin(classes.GPUDebugCommandsMixin):
     # whole class is likely going to be solved better: https://github.com/pygfx/wgpu-py/pull/546
-    def push_debug_group(self, group_label: str | None = None) -> None:
+    def push_debug_group(self, group_label: str) -> None:
         c_group_label = to_c_string_view(group_label)
         # H: void wgpuCommandEncoderPushDebugGroup(WGPUCommandEncoder commandEncoder, WGPUStringView groupLabel)
         # H: void wgpuComputePassEncoderPushDebugGroup(WGPUComputePassEncoder computePassEncoder, WGPUStringView groupLabel)
@@ -3017,7 +3014,7 @@ def pop_debug_group(self) -> None:
         function = type(self)._pop_debug_group_function
         function(self._internal)
 
-    def insert_debug_marker(self, marker_label: str | None = None) -> None:
+    def insert_debug_marker(self, marker_label: str) -> None:
         c_marker_label = to_c_string_view(marker_label)
         # H: void wgpuCommandEncoderInsertDebugMarker(WGPUCommandEncoder commandEncoder, WGPUStringView markerLabel)
         # H: void wgpuComputePassEncoderInsertDebugMarker(WGPUComputePassEncoder computePassEncoder, WGPUStringView markerLabel)
@@ -3039,7 +3036,7 @@ def _write_timestamp(self, query_set, query_index):
 
 
 class GPURenderCommandsMixin(classes.GPURenderCommandsMixin):
-    def set_pipeline(self, pipeline: GPURenderPipeline | None = None) -> None:
+    def set_pipeline(self, pipeline: GPURenderPipeline) -> None:
         self._maybe_keep_alive(pipeline)
         pipeline_id = pipeline._internal
         # H: void wgpuRenderPassEncoderSetPipeline(WGPURenderPassEncoder renderPassEncoder, WGPURenderPipeline pipeline)
@@ -3049,8 +3046,8 @@ def set_pipeline(self, pipeline: GPURenderPipeline | None = None) -> None:
 
     def set_index_buffer(
         self,
-        buffer: GPUBuffer | None = None,
-        index_format: enums.IndexFormatEnum | None = None,
+        buffer: GPUBuffer,
+        index_format: enums.IndexFormatEnum,
         offset: int = 0,
         size: int | None = None,
     ) -> None:
@@ -3066,11 +3063,7 @@ def set_index_buffer(
         )
 
     def set_vertex_buffer(
-        self,
-        slot: int | None = None,
-        buffer: GPUBuffer | None = None,
-        offset: int = 0,
-        size: int | None = None,
+        self, slot: int, buffer: GPUBuffer, offset: int = 0, size: int | None = None
     ) -> None:
         self._maybe_keep_alive(buffer)
         if not size:
@@ -3082,7 +3075,7 @@ def set_vertex_buffer(
 
     def draw(
         self,
-        vertex_count: int | None = None,
+        vertex_count: int,
         instance_count: int = 1,
         first_vertex: int = 0,
         first_instance: int = 0,
@@ -3094,11 +3087,7 @@ def draw(
             self._internal, vertex_count, instance_count, first_vertex, first_instance
         )
 
-    def draw_indirect(
-        self,
-        indirect_buffer: GPUBuffer | None = None,
-        indirect_offset: int | None = None,
-    ) -> None:
+    def draw_indirect(self, indirect_buffer: GPUBuffer, indirect_offset: int) -> None:
         # self._maybe_keep_alive(indirect_buffer)
         buffer_id = indirect_buffer._internal
         # H: void wgpuRenderPassEncoderDrawIndirect(WGPURenderPassEncoder renderPassEncoder, WGPUBuffer indirectBuffer, uint64_t indirectOffset)
@@ -3108,7 +3097,7 @@ def draw_indirect(
 
     def draw_indexed(
         self,
-        index_count: int | None = None,
+        index_count: int,
         instance_count: int = 1,
         first_index: int = 0,
         base_vertex: int = 0,
@@ -3127,9 +3116,7 @@ def draw_indexed(
         )
 
     def draw_indexed_indirect(
-        self,
-        indirect_buffer: GPUBuffer | None = None,
-        indirect_offset: int | None = None,
+        self, indirect_buffer: GPUBuffer, indirect_offset: int
     ) -> None:
         self._maybe_keep_alive(indirect_buffer)
         buffer_id = indirect_buffer._internal
@@ -3342,7 +3329,7 @@ def _create_render_pass_stencil_attachment(self, ds_attachment):
         return c_depth_stencil_attachment
 
     def clear_buffer(
-        self, buffer: GPUBuffer | None = None, offset: int = 0, size: int | None = None
+        self, buffer: GPUBuffer, offset: int = 0, size: int | None = None
     ) -> None:
         offset = int(offset)
         if offset % 4 != 0:  # pragma: no cover
@@ -3367,10 +3354,10 @@ def clear_buffer(
 
     def copy_buffer_to_buffer(
         self,
-        source: GPUBuffer | None = None,
-        source_offset: int | None = None,
-        destination: GPUBuffer | None = None,
-        destination_offset: int | None = None,
+        source: GPUBuffer,
+        source_offset: int,
+        destination: GPUBuffer,
+        destination_offset: int,
         size: int | None = None,
     ) -> None:
         if source_offset % 4 != 0:  # pragma: no cover
@@ -3398,9 +3385,9 @@ def copy_buffer_to_buffer(
 
     def copy_buffer_to_texture(
         self,
-        source: structs.TexelCopyBufferInfoStruct | None = None,
-        destination: structs.TexelCopyTextureInfoStruct | None = None,
-        copy_size: tuple[int, int, int] | structs.Extent3DStruct | None = None,
+        source: structs.TexelCopyBufferInfoStruct,
+        destination: structs.TexelCopyTextureInfoStruct,
+        copy_size: tuple[int, int, int] | structs.Extent3DStruct,
     ) -> None:
         check_struct("TexelCopyBufferInfo", source)
         check_struct("TexelCopyTextureInfo", destination)
@@ -3464,9 +3451,9 @@ def copy_buffer_to_texture(
 
     def copy_texture_to_buffer(
         self,
-        source: structs.TexelCopyTextureInfoStruct | None = None,
-        destination: structs.TexelCopyBufferInfoStruct | None = None,
-        copy_size: tuple[int, int, int] | structs.Extent3DStruct | None = None,
+        source: structs.TexelCopyTextureInfoStruct,
+        destination: structs.TexelCopyBufferInfoStruct,
+        copy_size: tuple[int, int, int] | structs.Extent3DStruct,
     ) -> None:
         check_struct("TexelCopyTextureInfo", source)
         check_struct("TexelCopyBufferInfo", destination)
@@ -3530,9 +3517,9 @@ def copy_texture_to_buffer(
 
     def copy_texture_to_texture(
         self,
-        source: structs.TexelCopyTextureInfoStruct | None = None,
-        destination: structs.TexelCopyTextureInfoStruct | None = None,
-        copy_size: tuple[int, int, int] | structs.Extent3DStruct | None = None,
+        source: structs.TexelCopyTextureInfoStruct,
+        destination: structs.TexelCopyTextureInfoStruct,
+        copy_size: tuple[int, int, int] | structs.Extent3DStruct,
     ) -> None:
         check_struct("TexelCopyTextureInfo", source)
         check_struct("TexelCopyTextureInfo", destination)
@@ -3607,11 +3594,11 @@ def finish(self, *, label: str = "") -> GPUCommandBuffer:
 
     def resolve_query_set(
         self,
-        query_set: GPUQuerySet | None = None,
-        first_query: int | None = None,
-        query_count: int | None = None,
-        destination: GPUBuffer | None = None,
-        destination_offset: int | None = None,
+        query_set: GPUQuerySet,
+        first_query: int,
+        query_count: int,
+        destination: GPUBuffer,
+        destination_offset: int,
     ) -> None:
         # H: void f(WGPUCommandEncoder commandEncoder, WGPUQuerySet querySet, uint32_t firstQuery, uint32_t queryCount, WGPUBuffer destination, uint64_t destinationOffset)
         libf.wgpuCommandEncoderResolveQuerySet(
@@ -3646,14 +3633,14 @@ class GPUComputePassEncoder(
     # GPUObjectBaseMixin
     _release_function = libf.wgpuComputePassEncoderRelease
 
-    def set_pipeline(self, pipeline: GPUComputePipeline | None = None) -> None:
+    def set_pipeline(self, pipeline: GPUComputePipeline) -> None:
         pipeline_id = pipeline._internal
         # H: void f(WGPUComputePassEncoder computePassEncoder, WGPUComputePipeline pipeline)
         libf.wgpuComputePassEncoderSetPipeline(self._internal, pipeline_id)
 
     def dispatch_workgroups(
         self,
-        workgroup_count_x: int | None = None,
+        workgroup_count_x: int,
         workgroup_count_y: int = 1,
         workgroup_count_z: int = 1,
     ) -> None:
@@ -3663,9 +3650,7 @@ def dispatch_workgroups(
         )
 
     def dispatch_workgroups_indirect(
-        self,
-        indirect_buffer: GPUBuffer | None = None,
-        indirect_offset: int | None = None,
+        self, indirect_buffer: GPUBuffer, indirect_offset: int
     ) -> None:
         buffer_id = indirect_buffer._internal
         # H: void f(WGPUComputePassEncoder computePassEncoder, WGPUBuffer indirectBuffer, uint64_t indirectOffset)
@@ -3715,12 +3700,12 @@ class GPURenderPassEncoder(
 
     def set_viewport(
         self,
-        x: float | None = None,
-        y: float | None = None,
-        width: float | None = None,
-        height: float | None = None,
-        min_depth: float | None = None,
-        max_depth: float | None = None,
+        x: float,
+        y: float,
+        width: float,
+        height: float,
+        min_depth: float,
+        max_depth: float,
     ) -> None:
         # H: void f(WGPURenderPassEncoder renderPassEncoder, float x, float y, float width, float height, float minDepth, float maxDepth)
         libf.wgpuRenderPassEncoderSetViewport(
@@ -3733,21 +3718,14 @@ def set_viewport(
             float(max_depth),
         )
 
-    def set_scissor_rect(
-        self,
-        x: int | None = None,
-        y: int | None = None,
-        width: int | None = None,
-        height: int | None = None,
-    ) -> None:
+    def set_scissor_rect(self, x: int, y: int, width: int, height: int) -> None:
         # H: void f(WGPURenderPassEncoder renderPassEncoder, uint32_t x, uint32_t y, uint32_t width, uint32_t height)
         libf.wgpuRenderPassEncoderSetScissorRect(
             self._internal, int(x), int(y), int(width), int(height)
         )
 
     def set_blend_constant(
-        self,
-        color: tuple[float, float, float, float] | structs.ColorStruct | None = None,
+        self, color: tuple[float, float, float, float] | structs.ColorStruct
     ) -> None:
         if isinstance(color, dict):
             check_struct("Color", color)
@@ -3763,7 +3741,7 @@ def set_blend_constant(
         # H: void f(WGPURenderPassEncoder renderPassEncoder, WGPUColor const * color)
         libf.wgpuRenderPassEncoderSetBlendConstant(self._internal, c_color)
 
-    def set_stencil_reference(self, reference: int | None = None) -> None:
+    def set_stencil_reference(self, reference: int) -> None:
         # H: void f(WGPURenderPassEncoder renderPassEncoder, uint32_t reference)
         libf.wgpuRenderPassEncoderSetStencilReference(self._internal, int(reference))
 
@@ -3771,7 +3749,7 @@ def end(self) -> None:
         # H: void f(WGPURenderPassEncoder renderPassEncoder)
         libf.wgpuRenderPassEncoderEnd(self._internal)
 
-    def execute_bundles(self, bundles: Sequence[GPURenderBundle] | None = None) -> None:
+    def execute_bundles(self, bundles: Sequence[GPURenderBundle]) -> None:
         bundle_ids = [bundle._internal for bundle in bundles]
         c_bundle_info = new_array("WGPURenderBundle[]", bundle_ids)
         # H: void f(WGPURenderPassEncoder renderPassEncoder, size_t bundleCount, WGPURenderBundle const * bundles)
@@ -3779,7 +3757,7 @@ def execute_bundles(self, bundles: Sequence[GPURenderBundle] | None = None) -> N
             self._internal, len(bundles), c_bundle_info
         )
 
-    def begin_occlusion_query(self, query_index: int | None = None) -> None:
+    def begin_occlusion_query(self, query_index: int) -> None:
         # H: void f(WGPURenderPassEncoder renderPassEncoder, uint32_t queryIndex)
         libf.wgpuRenderPassEncoderBeginOcclusionQuery(self._internal, int(query_index))
 
@@ -3884,7 +3862,7 @@ class GPUQueue(classes.GPUQueue, GPUObjectBase):
     # GPUObjectBaseMixin
     _release_function = libf.wgpuQueueRelease
 
-    def submit(self, command_buffers: Sequence[GPUCommandBuffer] | None = None) -> None:
+    def submit(self, command_buffers: Sequence[GPUCommandBuffer]) -> None:
         command_buffer_ids = [cb._internal for cb in command_buffers]
         c_command_buffers = new_array("WGPUCommandBuffer[]", command_buffer_ids)
         # H: void f(WGPUQueue queue, size_t commandCount, WGPUCommandBuffer const * commands)
@@ -3892,9 +3870,9 @@ def submit(self, command_buffers: Sequence[GPUCommandBuffer] | None = None) -> N
 
     def write_buffer(
         self,
-        buffer: GPUBuffer | None = None,
-        buffer_offset: int | None = None,
-        data: ArrayLike | None = None,
+        buffer: GPUBuffer,
+        buffer_offset: int,
+        data: ArrayLike,
         data_offset: int = 0,
         size: int | None = None,
     ) -> None:
@@ -3969,10 +3947,10 @@ def read_buffer(
 
     def write_texture(
         self,
-        destination: structs.TexelCopyTextureInfoStruct | None = None,
-        data: ArrayLike | None = None,
-        data_layout: structs.TexelCopyBufferLayoutStruct | None = None,
-        size: tuple[int, int, int] | structs.Extent3DStruct | None = None,
+        destination: structs.TexelCopyTextureInfoStruct,
+        data: ArrayLike,
+        data_layout: structs.TexelCopyBufferLayoutStruct,
+        size: tuple[int, int, int] | structs.Extent3DStruct,
     ) -> None:
         # Note that the bytes_per_row restriction does not apply for
         # this function; wgpu-native deals with it.