forge-instanced-rendering

Instanced rendering works by streaming per-instance transforms, allowing many copies of the same mesh to be drawn in a single draw call. A dual-vertex buffer pipeline supplies per-vertex data and a 64-byte model matrix per instance to reconstruct geometry via a shared VP matrix.

To set up per-instance data for instanced rendering, create an array of InstanceData containing a 64-byte model matrix for each instance. Upload this as a per-instance buffer alongside your per-vertex buffer, then issue a single instanced draw to render the scene.

The best way to render many identical meshes with individual transforms is instanced rendering. It uses a dual-vertex buffer pipeline with seven vertex attributes, reconstructing the model matrix from per-instance data in the vertex shader to efficiently draw repeated geometry like particles or buildings.

Yes, instanced rendering requires a separate per-instance buffer for transforms. The dual-vertex buffer pipeline uses one buffer for per-vertex data and another to store the 64-byte model matrix per instance, enabling the shader to apply individual transforms to repeated geometry.

You should use instanced rendering instead of individual draw calls when rendering scenes with repeated geometry requiring individual transforms, such as forests, crowds, particle systems, or buildings. It batches many copies of the same mesh into a single draw call for efficiency.

Yes, you can reconstruct the model matrix from instance data in a vertex shader. The shader uses seven vertex attributes representing per-instance matrix columns and per-vertex attributes, combining this per-instance data with a shared VP matrix to render the final geometry.