private void ParseGeometry(
GameObject[] roots,
ref SceneParseResult sceneParseResult)
{
var renderers = GetAllRenderers(roots);
if (!IsAllGeometriesDirty(renderers) && sceneParseResult.Primitives.Count != 0)
{
// All the geometries are unchange, no need to rebuild
return;
}
// TODO: Optimize dynamic array generation
sceneParseResult.ClearAllPrimitives();
sceneParseResult.ClearAllGeometries();
sceneParseResult.ClearAllMaterials();
sceneParseResult.ClearTopLevelBVH();
foreach (var renderer in renderers)
{
if (renderer.gameObject.activeInHierarchy)
{
RTMaterial material = renderer.material;
if (renderer.geometry == null || !renderer.geometry.IsGeometryValid() || material == null)
{
continue;
}
var closestShaderGUID = renderer.material.GetClosestHitGUID();
int closestShaderIndex = CustomShaderDatabase.Instance.GUIDToShaderIndex(closestShaderGUID, EShaderType.ClosestHit);
var intersectShaderGUID = renderer.geometry.GetIntersectShaderGUID();
int intersectShaderIndex = CustomShaderDatabase.Instance.GUIDToShaderIndex(intersectShaderGUID, EShaderType.Intersect);
if (!sceneParseResult.GeometryStride.ContainsKey(intersectShaderIndex))
{
sceneParseResult.GeometryStride.Add(intersectShaderIndex, renderer.geometry.IsAccelerationStructure() ? 0 : renderer.geometry.GetStride());
}
if (renderer.geometry.IsAccelerationStructure())
{
// Such as Low-Level BVH (RTMeshBVH)
int mapOffset = sceneParseResult.ObjectLevelAccGeoMapCursor(intersectShaderIndex);
int geoOffset = sceneParseResult.ObjectLevelAccGeoCursor(intersectShaderIndex);
((IRTMeshBVH)(renderer.geometry)).BuildBVHAndTriangleList(geoLocalToGlobalIndexOffset: geoOffset,
mappingLocalToGlobalIndexOffset: mapOffset);
List <float> geoInsData = renderer.geometry.GetGeometryInstanceData(geoLocalToGlobalIndexOffset: geoOffset,
mappingLocalToGlobalIndexOffset: mapOffset);
sceneParseResult.AddAccelerationStructureGeometry(
accelerationStructureData: geoInsData,
accelGeometryMapping: renderer.geometry.GetAccelerationStructureGeometryMapping(geoLocalToGlobalIndexOffset: geoOffset,
mappingLocalToGlobalIndexOffset: mapOffset),
accelGeometryData: renderer.geometry.GetAccelerationStructureGeometryData(geoLocalToGlobalIndexOffset: geoOffset,
mappingLocalToGlobalIndexOffset: mapOffset),
intersectIndex: intersectShaderIndex
);
}
else
{
// Standardized Geometry (Sphere, Triangle)
List <float> geoInsData = renderer.geometry.GetGeometryInstanceData(geoLocalToGlobalIndexOffset: 0, mappingLocalToGlobalIndexOffset: 0); // No offset
sceneParseResult.AddGeometryData(
geometryData: geoInsData,
intersectIndex: intersectShaderIndex
);
}
int startIndex = sceneParseResult.AddGeometryCount(
count: renderer.geometry.GetCount(),
intersectIndex: intersectShaderIndex
);
int materialInstanceIndex = sceneParseResult.AddMaterial(material);
sceneParseResult.AddWorldToPrimitive(renderer.gameObject.transform.worldToLocalMatrix);
sceneParseResult.AddPrimitive(new Primitive(
geometryIndex: intersectShaderIndex,
geometryInstanceBegin: startIndex,
geometryInstanceCount: renderer.geometry.GetCount(),
materialIndex: closestShaderIndex,
materialInstanceIndex: materialInstanceIndex,
transformIndex: sceneParseResult.WorldToPrimitive.Count - 1
));
var boxOfThisObject = renderer.geometry.GetTopLevelBoundingBox(assginedPrimitiveId: sceneParseResult.Primitives.Count - 1);
sceneParseResult.AddBoundingBox(boxOfThisObject);
}
}
}