raisin::StreamedTerrain

class · #include <rayrai/StreamedTerrain.hpp>

A complete visual terrain cover with small patches near observers and coarse patches toward the horizon. Update on the viewer's GL thread. Replacements are prepared within an upload budget; the previous cover stays visible until its complete replacement is ready. Physics is owned by the caller. The height provider must support the entire world bounds. The viewer/context must outlive this owner; prefixed visuals are owned here.

Nested classes

• struct Settings — Layout and per-patch geometry parameters.

Constructors & destructor

StreamedTerrain

StreamedTerrain(
    RayraiWindow &viewer,
    std::string prefix,
    WorldCellBounds world,
    TerrainPatch::HeightFunction height,
    Material material,
    Settings settings)

Parameters

Parameter	Description
viewer	Viewer that owns the patch visuals; must outlive this object.
prefix	Name prefix; visuals are named prefix/depth/x/y.
world	World rectangle covered by the terrain.
height	Height function valid over all of world.
material	Material assigned to every patch mesh.
settings	Layout parameters.

Exceptions

Exception	Description
std::invalid_argument	for invalid settings; std::length_error if even the coarse layout exceeds the patch budget.

StreamedTerrain(const StreamedTerrain &) = delete

~StreamedTerrain

~StreamedTerrain()

Public member functions

operator=

StreamedTerrain &operator=(const StreamedTerrain &) = delete

update

size_t update(
    std::span<const glm::dvec2> observers,
    double focalPixels,
    double pixelError=1,
    bool lodEnabled=true)

Advance layout preparation and re-select patch LODs. Empty observers retain a single coarse world patch. Horizontal distance is conservative for the terrain projection error used here.

Parameters

Parameter	Description
observers	Horizontal observer positions.
focalPixels	Projection focal length in pixels.
pixelError	Allowed screen-space height error in pixels.
lodEnabled	False keeps every patch at full resolution.

Returns Number of patches of the pending layout still awaiting preparation.

clear

void clear()

Remove all patch visuals and forget the layout.

residentPatchCount

size_t residentPatchCount() const

Returns Patch count of the currently visible layout.

preparedPatchCount

size_t preparedPatchCount() const

Returns Visible patches plus newly prepared patches of the pending layout.

selectedTriangleCount

size_t selectedTriangleCount() const

Returns Triangles (including skirts) of the selected LOD of every visible patch.

regions

std::vector<TerrainPatchRegion> regions() const

Returns Regions of the currently visible layout.