UI Rasterizer Module

Description

The concrete Renderer Module that draws the UI control tree. It renders every Vulkan Control as an instanced quad into an offscreen image, which the compositor then blends over the game output. One draw call covers all controls; per-control data lives in GPU buffers indexed by instance.

API summary

Member	Kind	Summary
`RendererStage`	override	`UI`.
`PrepareObjects()`	override	Builds the `MCUI` mesh, subscribes to the `Controls` entity group’s `onChanged`, prepares the camera.
`UpdateModule(frame)`	override	Rebuilds the per-control instance buffer + descriptor pool/sets for the dirty frame; queues stale resources for deferred deletion.
`CreatePipeline()`	override	`UIRasterizer/UI.vert+frag`, alpha blending, dynamic viewport/scissor.
`CreateRenderPass()`	override	Single color attachment, final layout `ShaderReadOnlyOptimal` so the compositor can sample it.
`WriteCommandBuffers(frame)`	override	Binds the pipeline, sets viewport/scissor, issues the instanced indexed draw.

Fields & Properties

// set 0: camera UBO (0), transforms SSBO (1), per-control data SSBO array (2, variable)
// set 1: mask/texture sampler array (0, variable)
internal override int variableSetCount => 2;

internal static MCUI meshComponent;                 // the quad mesh + instancing
internal override IReadOnlyList<Entity> renderEntities { get; set; }  // the Controls group

internal List<DeferredResources>[] deferredDeletions; // buffers/pools freed N frames later

Descriptor counts are sized generously (50 000) with VariableDescriptorCountBit | PartiallyBoundBit on the last binding of each set, so the control count can grow without recreating layouts. See the descriptor discussion in VULKAN.

Methods

Dirtying

The module is marked dirty (all frames) whenever the Controls group changes (add/remove) via OnControlsChanged, and whenever layout changes — UILayout.ResolveLayout() → the renderer’s UpdateModules(). A dirty frame triggers a full instance-buffer + descriptor rebuild in UpdateModule.

Drawing

WriteCommandBuffer begins the render pass, binds the pipeline, sets the dynamic viewport/scissor from the window size, then MCUI.EnqueueDrawCommands binds both descriptor sets and issues one CmdDrawIndexed with instanceCount = controlCount.

Helpers

private void CreateSampler();                 // anisotropic repeat sampler for control textures
private void CreateCircleSDF(...);            // procedural SDF helpers (mask experiments)

Renderer Module — the base class
Vulkan Control — the entities this module renders
VULKAN — renderer system + descriptor strategy