onBeforeRender property

@override OnRender? get onBeforeRender

Implementation

@override
	OnRender? get onBeforeRender =>({
  WebGLRenderer? renderer,
  RenderTarget? renderTarget,
  Object3D? mesh,
  Scene? scene,
  Camera? camera,
  BufferGeometry? geometry,
  Material? material,
  Map<String, dynamic>? group
}){
		// if visibility has not changed and frustum culling and object sorting is not required
		// then skip iterating over all items
		if ( ! this._visibilityChanged && ! this.perObjectFrustumCulled && ! this.sortObjects ) {
			return null;
		}

		// the indexed version of the multi draw function requires specifying the start
		// offset in bytes.
		final index = geometry!.getIndex();
		final bytesPerElement = index == null ? 1 : index.array.BYTES_PER_ELEMENT;

		final instanceInfo = _instanceInfo;
		final multiDrawStarts = this.multiDrawStarts;
		final multiDrawCounts = this.multiDrawCounts;
		final geometryInfoList = _geometryInfo;
		final perObjectFrustumCulled = this.perObjectFrustumCulled;
		final indirectTexture = this.indirectTexture;
		final indirectArray = indirectTexture?.image.data;

		// prepare the frustum in the local frame
		if ( perObjectFrustumCulled ) {

			_matrix.multiply2( camera!.projectionMatrix, camera.matrixWorldInverse )
				.multiply( this.matrixWorld );
			_frustum.setFromMatrix(
				_matrix,
				renderer!.coordinateSystem
			);
		}

		int multiDrawCount = 0;
		if ( this.sortObjects ) {

			// get the camera position in the local frame
			_matrix.setFrom( this.matrixWorld ).invert();
			_vector.setFromMatrixPosition( camera!.matrixWorld ).applyMatrix4( _matrix );
			_forward.setValues( 0, 0, - 1 ).transformDirection( camera.matrixWorld ).transformDirection( _matrix );

			for (int i = 0, l = instanceInfo.length; i < l; i ++ ) {
				if ( instanceInfo[ i ].visible && instanceInfo[ i ].active ) {

					final geometryId = instanceInfo[ i ].geometryIndex;

					// get the bounds in world space
					this.getMatrixAt( i, _matrix );
					this.getBoundingSphereAt( geometryId, _sphere ).applyMatrix4( _matrix );

					// determine whether the batched geometry is within the frustum
					bool culled = false;
					if ( perObjectFrustumCulled ) {
						culled = ! _frustum.intersectsSphere( _sphere );
					}

					if ( ! culled ) {
						// get the distance from camera used for sorting
						final geometryInfo = geometryInfoList[ geometryId ];
						final z = _temp.sub2( _sphere.center, _vector ).dot( _forward );
						_renderList.push( geometryInfo.start, geometryInfo.count, z.toInt(), i );
					}
				}
			}

			// Sort the draw ranges and prep for rendering
			final list = _renderList.list;
			final customSort = this.customSort;
			if ( customSort == null ) {
				list.sort( material?.transparent != null? sortTransparent : sortOpaque );
			} else {
				customSort.call( this, list, camera );
			}

			for (int i = 0, l = list.length; i < l; i ++ ) {
				final item = list[ i ];
				multiDrawStarts[ multiDrawCount ] = item.start * bytesPerElement;
				multiDrawCounts[ multiDrawCount ] = item.count;
				indirectArray[ multiDrawCount ] = item.index;
				multiDrawCount ++;
			}

			_renderList.reset();

		} else {
			for ( int i = 0, l = instanceInfo.length; i < l; i ++ ) {
				if ( instanceInfo[ i ].visible && instanceInfo[ i ].active ) {

					final geometryId = instanceInfo[ i ].geometryIndex;

					// determine whether the batched geometry is within the frustum
					bool culled = false;
					if ( perObjectFrustumCulled ) {
						// get the bounds in world space
						this.getMatrixAt( i, _matrix );
						this.getBoundingSphereAt( geometryId, _sphere ).applyMatrix4( _matrix );
						culled = ! _frustum.intersectsSphere( _sphere );
					}

					if ( ! culled ) {
						final geometryInfo = geometryInfoList[ geometryId ];
						multiDrawStarts[ multiDrawCount ] = geometryInfo.start * bytesPerElement;
						multiDrawCounts[ multiDrawCount ] = geometryInfo.count;
						indirectArray[ multiDrawCount ] = i;
						multiDrawCount ++;
					}
				}
			}
		}

		indirectTexture?.needsUpdate = true;
		this.multiDrawCount = multiDrawCount;
		this._visibilityChanged = false;

  return null;
};

set onBeforeRender (OnRender? _onBeforeRender)

Implementation

OnRender? onBeforeRender;