ShadowAtlas (Mibo)

ShadowAtlas Type

Namespace: Mibo.Elmish.Graphics3D.Pipelines
Assembly: Mibo.MonoGame.dll
Base Type: obj

Manages a texture atlas for multiple shadow maps. MonoGame port of the canonical raylib ShadowAtlas.

The atlas is a single square RenderTarget2D with SurfaceFormat.Single (R32F) — MonoGame cannot create a sampleable depth-only render target on either backend (depth buffers are non-sampleable), so the shadow depth is written into the color attachment via DepthShadow.fx (non-linear position.z to .r). The forward pass samples it with a comparison sampler (SamplerState.ComparisonFunction) for hardware PCF — no textureSize or manual 3×3 loop required (SM3.0-clean).

The render target is allocated lazily against the real GraphicsDevice on first ShadowAtlas.EnsureResources call (mirrors the B5/B8 lazy-effect pattern) — GraphicsDevice is not available at pipeline construction time.

Constructors

Constructor	Description
`ShadowAtlas(config, biasConfig)` Full Usage: `ShadowAtlas(config, biasConfig)` Parameters: config : `ShadowAtlasConfig` biasConfig : `ShadowBiasConfig` Returns: `ShadowAtlas`	config : `ShadowAtlasConfig` biasConfig : `ShadowBiasConfig` Returns: `ShadowAtlas`

Instance members

Instance member	Description
`this.ActiveCasterCount` Full Usage: `this.ActiveCasterCount` Returns: `int`	Get the number of active caster regions (computed by PrepareUniforms). Returns: `int`
`this.AddCaster` Full Usage: `this.AddCaster` Parameters: casterType : `ShadowCasterType` lightPosition : `Vector3` lightDirection : `Vector3` lightTarget : `Vector3` enabled : `bool` biasOverride : `float32 voption` Returns: `int<MeasureProduct<ShadowCasterId, MeasureOne>> voption`	Register a new shadow caster and allocate atlas regions. Returns the caster ID, or ValueNone if the atlas is full. casterType : `ShadowCasterType` lightPosition : `Vector3` lightDirection : `Vector3` lightTarget : `Vector3` enabled : `bool` biasOverride : `float32 voption` Returns: `int<MeasureProduct<ShadowCasterId, MeasureOne>> voption`
`this.BiasConfig` Full Usage: `this.BiasConfig` Returns: `ShadowBiasConfig`	The bias configuration. Returns: `ShadowBiasConfig`
`this.Biases` Full Usage: `this.Biases` Returns: `float32 array`	Returns: `float32 array`
`this.CasterTypes` Full Usage: `this.CasterTypes` Returns: `int array`	Returns: `int array`
`this.Casters` Full Usage: `this.Casters` Returns: `ValueCollection<int<MeasureProduct<ShadowCasterId, MeasureOne>>, ShadowCasterData>`	Get all active casters (for iteration). Returns: `ValueCollection<int<MeasureProduct<ShadowCasterId, MeasureOne>>, ShadowCasterData>`
`this.Clear` Full Usage: `this.Clear`	Clear all casters and reset slot allocator. Call at start of each frame.
`this.Config` Full Usage: `this.Config` Returns: `ShadowAtlasConfig`	The atlas configuration. Returns: `ShadowAtlasConfig`
`this.Count` Full Usage: `this.Count` Returns: `int`	Number of currently allocated casters. Returns: `int`
`this.EnsureResources` Full Usage: `this.EnsureResources` Parameters: gd : `GraphicsDevice`	Lazily allocate the render target against the real `GraphicsDevice`. Called on first shadow pass (the device isn't available at construction). gd : `GraphicsDevice`
`this.Fbo` Full Usage: `this.Fbo` Returns: `RenderTarget2D`	The shadow depth render target (R32F color attachment). Returns: `RenderTarget2D`
`this.GetBias` Full Usage: `this.GetBias` Parameters: caster : `ShadowCasterData` Returns: `float32`	Get bias for a caster type, respecting per-caster override. caster : `ShadowCasterData` Returns: `float32`
`this.GetRegionViewProj` Full Usage: `this.GetRegionViewProj` Parameters: regionIndex : `int` Returns: `Matrix`	Get the view-projection matrix for a specific atlas region. Returns `Matrix.Identity` when the region has no VP set. Use this to read back a caster's VP — `ShadowCasterData.ViewProj` is a struct field that is NOT kept in sync with the region store (it stays `Identity` after `AddCaster`); the authoritative copy lives in the region dictionary. regionIndex : `int` Returns: `Matrix`
`this.GetRegionViewport` Full Usage: `this.GetRegionViewport` Parameters: regionIndex : `int` Returns: `Viewport`	Get a Viewport for a region index. regionIndex : `int` Returns: `Viewport`
`this.GetUVOffsetScale` Full Usage: `this.GetUVOffsetScale` Parameters: regionIndex : `int` Returns: `Vector4`	Get UV offset/scale for a region index (xy=offset, zw=scale). regionIndex : `int` Returns: `Vector4`
`this.GridSize` Full Usage: `this.GridSize` Returns: `int`	Grid size (rows/columns) of the atlas. Returns: `int`
`this.LightPositions` Full Usage: `this.LightPositions` Returns: `Vector3 array`	Returns: `Vector3 array`
`this.PrepareUniforms` Full Usage: `this.PrepareUniforms`	Prepare uniform arrays for upload to the forward shader. Call each frame before uploading shadow uniforms.
`this.RegionSize` Full Usage: `this.RegionSize` Returns: `int`	Size of each region in pixels. Returns: `int`
`this.Release` Full Usage: `this.Release`	Releases the render target. Called from `ForwardPipeline.Shutdown`.
`this.RemoveCaster` Full Usage: `this.RemoveCaster` Parameters: id : `int<MeasureProduct<ShadowCasterId, MeasureOne>>`	Remove a shadow caster and free its atlas regions. id : `int<MeasureProduct<ShadowCasterId, MeasureOne>>`
`this.SetRegionViewProj` Full Usage: `this.SetRegionViewProj` Parameters: regionIndex : `int` vp : `Matrix`	Set the view-projection matrix for a specific atlas region. regionIndex : `int` vp : `Matrix`
`this.UVOffsets` Full Usage: `this.UVOffsets` Returns: `Vector4 array`	Returns: `Vector4 array`
`this.ViewProjs` Full Usage: `this.ViewProjs` Returns: `Matrix array`	Get prepared uniform arrays (call after PrepareUniforms). Returns: `Matrix array`