Displacement map vertex shader would be a cool feature to implement.

Managed to prepare a project with displacement effect by replacing transformVS.

Here is the Project Link (Working properly with lights and shadows)

Screenshots

Displacement Effect in use:

My try on trying to create it in engine: (can provide a PR but it is not working as intended)

• Tried to implement the effect with if(options.useDisplacement) code+= #define DISPLACEMENT in shader definition.
• Thus, in vert/transform.js #ifdef DISPLACEMENT seems not picking while rendering shadows.

Screenshots

Issues while engine implementation :

• Displacement state needs to be stated in transformVS. (matrix_normal * sample_texture will throw error otherwise because of undefined texture)
• This leads to some issues like lights not getting definitions from lit options. Which is causing lighting artifacts.
• Another approach might be code += displacementVS.

Recommendations:

• Soft limiting in UI displacementMapFactor within -2, 2 range would be good.
• Offsetting displacementMapFactorOffset would be good implementation for manually defining boundaries