API Reference

Types and members in Ava3D, grouped by topic.

Controls

The one type you add to a window, when it decides to draw, and what it keeps on the card between scenes.

Type	Description
Ava3DView	A 3D view that works on every platform Avalonia targets, including the browser.
RenderTrigger	When `Ava3DView` draws a frame.
SwapPolicy	What happens on the frame after `Ava3DView.Scene` is assigned: draw the new scene at once, with stand-ins where its textures have not arrived, or keep showing the old one until they have.
ResourcePolicy	How long a view keeps textures and meshes on the card once nothing is drawing them, how much it may keep, and how much of each frame it spends copying new ones up.
Resources	Process-wide defaults for how resident resources are kept.
PrepareProgress	How far `Ava3DView.PrepareAsync` has got, reported through its `IProgress`.
ScenePreparation	What `Ava3DView.PrepareAsync` did, once it has finished.

Scene and camera

A tree of nodes with transforms and a camera to look at them with.

Type	Description
Scene	The scene: a root transform, its nodes, its lights and a background colour.
Node	A node in the scene graph: a transform, and children that inherit it.
MeshNode	A node that draws geometry.
MeshInstance	One copy of a mesh, and what makes it different from the others.
LevelOfDetail	A coarser version of a `MeshNode`'s mesh, drawn in its place from a distance onwards.
LevelOfDetailCollection	A node's levels of detail, in any order: they are sorted by distance when the scene is drawn.
NodeCollection	The children of a `Node`.
Camera	An orbit camera: a point it looks at, and a direction and distance it looks from.

Lights

As many as a scene wants, plus the ambient hemisphere that fills in everything they miss.

Type	Description
Light	What every light has in common.
DirectionalLight	A light with a direction but no position: the sun, and anything else far enough away that its rays arrive parallel.
PointLight	A light at a position, falling off with distance.
SpotLight	A light with a position, a direction and a cone: a torch, a stage lamp, a headlight.
LightCollection	The lights in a scene, in the order they were added.
EnvironmentLight	The light that comes from everywhere: the sky, the ground, the room.
EnvironmentImage	Immutable linear RGB radiance in an equirectangular image.
EnvironmentProbe	A baked room reflection with world-space box influence and box-projected specular parallax.
ProbeCaptureOptions	Settings for `EnvironmentProbe.CaptureAsync`.

Sprites, lines and points

The three things in a scene that are not lit triangles: billboards, segments and clouds.

Type	Description
SpriteNode	A textured quad that always faces the camera, centred on the node's position.
LineNode	Unlit line segments, transformed by the node's world matrix.
PointsNode	Unlit points, transformed by the node's world matrix.

Overlays and labels

Position Avalonia controls over a scene and render text on sprites.

Type	Description
Ava3DOverlay	Places ordinary Avalonia controls at positions in an `Ava3DView`'s scene.
OverlayAnchor	Which point of a child sits on the world position it is anchored to.
OverlayBehind	What to do with a child whose world position is not in front of the near plane.
OverlayOffScreen	What to do with a child whose projected point is outside the panel.
OverlayOcclusion	Whether a child is hidden when the scene is in front of the thing it is anchored to.
OcclusionPrecision	How exact an occlusion test is, against what it costs.
LabelNode	A line of text standing in the scene: a nameplate on a hull, a sign on a bulkhead, a caption on a plinth.
TextOptions	How a string becomes a texture.

Geometry

Vertex data, the shapes that come free, the box every node knows about itself, folding a static assembly into fewer of them, and a mesh from a signed-distance function.

Type	Description
Mesh	Triangle geometry, independent of where it sits in the world.
Primitives	Ready-made geometry, so a scene can be built without a model file.
BoundingBox	An axis-aligned box.
Batching	Folding a group's static surfaces into as few draws as they can be drawn in.
SurfaceNets	Turns a signed-distance field into a `Mesh`.
ScalarField	A signed distance: how far `point` is from a surface, negative inside it and positive outside.
SurfaceNetsOptions	What `SurfaceNets.Extract` is given beyond the field, the box and the resolution.
SurfaceNetsBudgetException	Thrown by `SurfaceNets.Extract` when the surface would have more triangles than `SurfaceNetsOptions.MaxTriangles` allows.

Math utilities

Rotations from directions, curves through waypoints, easing, and randomness you can repeat.

Type	Description
Rotations	Rotations built from directions rather than from angles.
Spline	A smooth curve through a row of points, and the direction it is going when it gets there.
Ease	Shaping a 0..1 parameter, so a move starts and stops instead of switching on and off.
Scatter	Repeatable randomness, indexed rather than drawn.

Materials and textures

Metallic-roughness parameters, the maps that drive them, and how a surface is composited.

Type	Description
Material	The surface appearance of a `MeshNode`: metallic-roughness PBR, the same model glTF 2.0 defines, so a loaded model looks the way its author intended rather than the way a viewer guessed.
AppearanceKind	What kind of thing an `AppearanceParameter` adjusts.
AppearanceParameter	One thing about a model a caller may adjust, with enough about it to build a control without knowing what the model is.
MaterialLookup	The materials of a loaded model, addressed by the names the file gave them.
BlendMode	How the fragments a material produces combine with what is already in the frame.
CullMode	Which side of a triangle is drawn.
Texture	An image: either encoded bytes (PNG or JPEG) or raw RGBA pixels.
TextureColorSpace	How the bytes of a `Texture` are encoded, when the slot they are put in should not be the one to decide.
TextureProgram	A texture whose pixels are computed rather than stored: a small program, evaluated over the surface, with the scene's clock as one of its inputs.
TextureMapping	Coordinates for one material texture.
TextureWrap	How a texture behaves outside 0..1.
TextureFilter	How a texture is sampled between its texels.
TextureFormat	A block-compressed texture format, as the hardware stores it.
UvSource	Which side of a triangle is rasterised.
MappingSpace	Whether a projection travels with the object or stays fixed in the world.
DetailLayer	The lights in a scene.
ShadingModel	How a surface turns light into colour.
MatcapTextureMode	Where a matcap's texture lives on the graphics card, which is a question only because the oldest tier this control runs on guarantees exactly eight sampler units and the mesh shader now has eight maps.
VertexAlphaMode	What the alpha channel of `Mesh.Colors` means on a material that is not transparent.

Animation

Play, blend and layer animation clips, with tracks, masks and playback events.

Type	Description
Animator	Plays clips over a node tree, one state at a time with a blend between the outgoing and the incoming.
AnimationClip	A named set of tracks — one animation as an authoring tool exported it.
AnimationTrack	One animated property of one node: a sorted key time array and the values at those times.
AnimationState	One clip as something that can be playing: its own time, speed, looping and blend weight.
AnimationStateCollection	The states an `Animator` knows, addressed by name.
AnimationLayer	One crossfading player: a set of states, which of them is playing, and how its pose meets the ones below it.
AnimationMask	Which nodes a layer is allowed to move.
AnimationBlend	How a layer combines with what is already posed beneath it.
AnimationInterpolation	How values between two keys are found.
AnimationPath	Which property of a node a track writes.
AnimationReference	What an additive layer measures its difference from.
AnimationEventArgs	The state a `Animator.Finished` event is about.

Skinning and morph targets

Deform meshes with skeleton joints and blendable vertex shapes.

Type	Description
Skin	A skeleton: the nodes that drive a skinned mesh, and the matrices that put the mesh into each of their spaces.
JointBinding	The four joints that move one vertex, and how much each of them does.
MorphShapes	The morph targets of a loaded model, addressed by name, with opposed pairs folded into one signed parameter each.
MorphWeights	Every morph target of a model by its own name, unpaired — `eye_large` and `eye_small` as two 0..1 weights rather than one signed parameter.

Model and texture loading

Turning a .glb or .gltf model or a .ktx2 texture into the types above, once, and instantiating it as often as it is on screen.

Type	Description
GltfLoader	Loads glTF into an Ava3D scene in one call.
GltfModel	Everything a `.glb` had in it: the nodes, and the clips, shapes and materials that drive them.
GltfAsset	A glTF file, read once.
GltfInstance	One copy of a `GltfAsset` in a scene: its own nodes to place and pose, its own `GltfInstance.Animator` and morph weights, sharing the asset's meshes and textures with every other copy.
GltfLoadOptions	How `GltfAsset.LoadAsync` reads a file.
InstantiateOptions	What `GltfAsset.Instantiate` is to make.
MaterialSharing	What an instance's materials are to the asset's.
GltfDiagnostic	One thing the reader could not carry over from a file, and why.
GltfDiagnosticKind	What kind of thing a `GltfDiagnostic` reports.
GltfException	A glTF file could not be read at all — it is not glTF, it is a version this reader does not know, its container is malformed — or it was read with `GltfLoadOptions.Validate` set and something in it had to be dropped.
IGltfResourceResolver	Where a `.gltf`'s external files come from.
GltfFileResolver	Resolves a `.gltf`'s URIs against a directory on disk.
GltfAvaloniaResolver	Resolves a `.gltf`'s URIs against an `avares://` location — the model shipped as an `AvaloniaResource` in the application, next to its textures.
GltfHttpResolver	Resolves a `.gltf`'s URIs over HTTP, which is how a browser build gets a model at all.
Ktx2Loader	Reads a KTX2 file into a `Texture`.

Picking

Which triangle of which node is under the pointer.

Type	Description
PickResult	What a ray through the scene hit.
PickEventArgs	Raised for every click when picking is enabled, whether or not anything was hit — a click on empty space reports a null `PickEventArgs.Result` rather than not being reported, because "the user deselected" is a thing an application needs to know.

Renderers

Which renderer you got, which ones the platform could offer, and why the others could not.

Type	Description
RenderInfo	What the control is actually doing, polled off the render thread.
ContactOcclusionQuality	Quality of depth-based contact occlusion.
MaterialDebugView	Diagnostic mesh views, selected with `Scene.DebugView`.
RendererFeature	One thing the active renderer either does or does not do, and what it costs when it does not.
RenderBackendKind	Which renderer to use, when the choice is not left to the control.
BackendOption	One entry in `RenderInfo.AvailableBackends`: a renderer, whether it can be selected, and a plain-language reason when it cannot.
BackendAvailability	Whether a `RenderBackendKind` can be selected, and if not, how close it is.
MissingComponent	Something a renderer needs that this machine does not have, and how to get it.
Rendering.Gl.PlatformSupport	The guard rail around the GL entry points that are fatal under WebAssembly.

Capturing a frame

One rendered frame of a view read back into memory — as shown, at another size, or with the Avalonia content over it — and drawing one with no view or window at all.

Type	Description
CaptureRequest	What to capture from an `Ava3DView`.
CapturedFrame	One frame of an `Ava3DView`, read back into memory.
CaptureFormat	What a `CapturedFrame` holds its pixels as.
CaptureQueueFullException	Thrown by `Ava3DView.CaptureAsync` when as many captures are already in flight on the view as `Ava3DView.CaptureQueueCapacity` allows.
Rendering.CameraSnapshot	The camera, frozen for one frame.
SceneRenderer	Renders a `Scene` to pixels with no window and no view — on a GPU where one can be had without either, and on the CPU where it cannot.
RenderOptions	How `SceneRenderer.RenderAsync` should draw.
RendererPreference	Which device `SceneRenderer.Create` should try for.
RendererKind	What a `SceneRenderer` turned out to draw with.

Diagnostics

A trace of what every frame cost, offline renders with their limits stated, checks of what this renderer computes, and the static frame capture kept for one release.

Type	Description
Diagnostics.FrameTrace	A bounded record of recent frames, for the questions `RenderInfo`'s averages cannot answer.
Diagnostics.FrameRecord	One frame as the trace saw it: what was built for it, what it cost on each thread, and what the caches did while it was drawn.
Diagnostics.PassTiming	What one render pass cost the card, where the backend can say.
Diagnostics.TraceFormat	The shapes `FrameTrace.Export` writes.
OfflineRenderer	Draws a scene into a `Texture`, with no window, no graphics context and no control.
OfflineRenderOptions	What an offline render is allowed to cost and how it should shade.
OfflineQuality	Which of the software renderer's two shading paths an offline render uses.
OfflineRenderResult	What an offline render produced, and what it left out.
SoftwareSettings	Process-wide settings for the software renderer — the CPU path a view falls back to when it can have no GPU, and the one `OfflineRenderer` draws with.
Diagnostics.PbrCalibration	A reproducible interior for comparing material channels, contact, shadows and reflections.
SelfTest	What this renderer computes, reduced to numbers that two machines can be compared on.
Diagnostics.FrameCapture	Writes one rendered frame to a PNG — the static, process-wide way, kept for one release.