Skip to content


Drawable help text


The Drawable shard defines an instance of a drawn object. It usually has a transform (in world space) and a mesh to draw.


The Params parameter contains a table of values that will be passed to the shader when this drawable is rendered.


See GFX.Feature about where shader parameters are defined and used.


Shader parameters and the drawable transform can be set as either constant parameters or dynamic ones.

Constant parameters

Constant parameters are passed through the input table. They are read and stay the same until this function is called again.

{:Mesh .mesh :Transform .transform} (GFX.Drawable) >= .my-drawable

Dynamic parameters

Dynamic parameters are passed as parameters to the shard. You can set the same fields as you can when setting constant parameters, with the exception of the mesh. The variables are referenced by the Drawable so that changes in their value will be reflect in the rendered result.

.. >= .dynamic-color
.. >= .dynamic-transform
{:Mesh .mesh} (Drawable :Transform .dynamic-transform :Params {:baseColor .dynamic-color}) >= .my-drawable

Intended usage

To avoid re-creating Drawables for objects with minor or no changes, you should set up Drawables from within a Setup block and pass their dynamic parameters to the shard.

; Only done once
  ... = .const-transform
  (Float4 1.0) >= .dynamic-color
  {:Mesh .mesh :Transform .const-transform} (Drawable :Params {:baseColor .dynamic-color}) >= .my-drawable)

; Update color every time this wire runs
... > .dynamic-color