How to Edit BIM Plys in BricsCAD BIM

Quick answer: BIM Ply Editing lets you manipulate all the composition plies in a model. Every drawing stores two independently toggleable settings: LEVELOFDETAIL (LOD) for composition plies, and RENDERCOMPOSITIONMATERIAL for their render materials.

Composition Plies and Render Materials

Composition plies display only when LEVELOFDETAIL is 2 (High), no selection needed, building elements adjust automatically. At 0 (Low), the solid’s own material definition is used instead. Toggle it from the ribbon’s Home tab or the Quad’s BIM tab.

Render materials display only when RENDERCOMPOSITIONMATERIAL is 1 (On), each ply’s render material comes from its material definition’s 3D Render Material setting. Toggle it the same way.

Materials only display visually when the current Visual Style’s Face Settings/Material Display is set to Materials and Textures (BIM, Modeling, and Realistic, for example), showing both composition plies and render materials together. If a composition’s render materials aren’t downloaded, or the composition itself is incorrect, the entity displays in red, a different red-flag from the incompatible-thickness one covered on this hub’s BIM data structure page.

The Four LOD/RCM Combinations

LOD	RCM	Result
0	0	The solid’s material definition is used; no materials display
2	0	The solid subdivides into plies with no materials shown; with face detection on, you can select individual ply faces to push/pull
0	1	The solid’s material definition is used, with exterior and interior face materials shown, the exterior layer’s material wraps around the whole object
2	1	The solid subdivides into plies, each displayed with its own material; with face detection on, you can select individual ply faces to push/pull

Manipulating Composition Plies

Make sure LEVELOFDETAIL is 2 (High).
Place the cursor near the ply you want to edit and press Tab until its face highlights, shown in the detected boundary colour (default 95, the same default confirmed on this hub’s selection methods page); face detection must be enabled.
Choose Push/Pull from the Quad and drag the ply to its new position.

Make sure DMPUSHPULLSUBTRACT is set to 1, so plies you push or pull get subtracted from any other 3D solids they intersect. Turn on ESNAP to snap precisely to a ply’s edge.

Creating a Rooftop Detail: A Worked Example

Beyond editing existing plies, you can build more complex details with extra solids layered on top.

Start with a roof-wall connection.
Click the Face detection icon in the ribbon to enable it.
Turn on LOD, click the ribbon icon or type LEVELOFDETAIL, then 2, and press Enter.
Hover over the edge of the floor slab’s concrete ply and press Tab to select its face.
Choose Push/Pull from the Model tab of the Quad.
Push/Pull that face out to the next ply of the wall.
To create a wall cap, select the wall’s top surface (Tab) and extrude it upward 50 mm (this cap isn’t classified yet).
Remove the section where the insulating building block will go: hover over the supporting wall and gypsum board’s surface, press Tab to select it, then extrude it up to the wall cap’s ply.
Extrude that same surface again; this creates a new solid.

Frequently Asked Questions

Why don’t my composition plies show up even though I’ve set LEVELOFDETAIL to 2? Make sure face detection is enabled, and check that the current Visual Style’s Face Settings/Material Display is set to Materials and Textures if you also expect to see rendered materials.

Why does my entity display in red after attaching a composition? Either its render materials haven’t downloaded, or the composition itself is incorrect, distinct from the separate red-flag for incompatible thickness covered elsewhere in this hub.

What does DMPUSHPULLSUBTRACT actually control? Whether plies being pushed or pulled get automatically subtracted from any other 3D solids they intersect; set it to 1 for this behaviour.

Which LOD/RCM combination lets me select and push/pull individual ply faces? LOD 2, with either RCM value, face detection needs LOD set to 2 regardless of whether materials render.