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Buffers to geometry

Buffers to geometry wraps GPU buffers in a geometry description. It does not infer a mesh layout from the bytes: formats, offsets, strides and draw settings must agree with the upstream producer. The output is Geometry, not a scene hierarchy.

Buffer and attribute setup

Connect buffers to Buffer 0–7. Each of the eight attribute slots has these controls:

Control Meaning
AttrN buffer Input buffer number, 0–7. -1 disables the attribute.
AttrN offset Byte offset from the beginning of the connected buffer view.
AttrN stride Byte distance between records. 0 uses the selected format’s tightly packed size.
AttrN format Component representation: Float, Half, unsigned/signed integer, short or normalized byte formats with the available component counts.
AttrN semantic Attribute meaning, such as position, normal, texcoord0 or color0. Custom attribute names are preserved for consumers that understand them.
AttrN instanced Advance this attribute per instance rather than per vertex.

Several attributes can refer to the same interleaved buffer. Their offsets differ but their record strides must match.

Draw settings

Control Meaning
Index Buffer Buffer 0–7 containing indices, or -1 for no index buffer.
Index Format UInt16 or UInt32.
Index Offset Byte offset into the connected index-buffer view.
Vertices Geometry draw count. Set it to match the intended draw; the process does not derive it from buffer size.
Instances Number of instances, starting at 1. Supply enough records for instanced attributes.
Topology Triangles, TriangleStrip, TriangleFan, Lines, LineStrip or Points.
Cull Mode None, Front or Back.
Front Face CounterClockwise or Clockwise winding.
Position, Rotation, Scale XYZ translation, Euler rotation in degrees and per-axis scale.

Example: tightly packed XYZ positions

  1. Use Array to buffer from Geometry and buffer utilities to convert [0, 0, 0, 1, 0, 0, 0, 1, 0] to Float32.
  2. Connect its output to Buffer 0.
  3. Set Attr0 buffer to 0, Attr0 format to Float3, Attr0 semantic to position, Attr0 offset to 0 and Attr0 stride to 12 bytes.
  4. Leave other attributes and Index Buffer at -1. Set Vertices to 3, Instances to 1, Topology to Triangles and Cull Mode to None.
  5. Inspect Geometry with Geometry Info before connecting it to the Render Pipeline.

For interleaved Float3 positions followed by Float3 normals, use a 24-byte stride for both attributes and offsets of 0 and 12 bytes respectively. The data format describes the existing bytes; selecting another format does not convert them.

Distinct library entries

Buffers to geometry (v1) is a separate registered process using numeric attribute locations. This page describes the current named-semantic version; use it for new patches unless an existing layout specifically requires v1. For extracting or reorganizing existing geometry, see Extract buffer and Repack attributes.