Transparency & alpha cut-outs
Drop a transparent PNG (a leaf, a logo, a fence) and 3dCMS clips the plane to the opaque pixels, so it shadows and reflects only where the image is solid.
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Not every texture is a solid rectangle. A leaf, a logo, a chain-link fence, a bit of foliage are all images with a transparent background, and 3dCMS renders them as proper alpha cut-outs: the plane shows (and casts shadows, and reflects) only where the image is opaque, with the see-through parts genuinely gone.
The automatic path
Drop a transparent PNG from the Asset Library (or import one) and 3dCMS detects the alpha channel and sets the resulting plane to cut-out mode for you. No material wiring needed. The Cut-out library filter gathers exactly these transparent images in one place.
Choosing the alpha mode by hand
On the Material Output node in the graph, an Alpha dropdown controls how the albedo's transparency is treated:
| Mode | What it does |
|---|---|
| Opaque | Ignores the alpha channel entirely: the whole rectangle renders solid. |
| Cutout (alpha clip) | Hard on/off per pixel. Above the cutoff it's fully solid (and casts a matching shadow); below it, the pixel is discarded. Crisp edges, cheap, and shadow-correct: the right choice for foliage and decals. |
| Blend (soft) | Smooth partial transparency, for glass and soft fades. Doesn't carve shadows the way Cutout does. |
Pick Cutout and an Alpha Cutoff slider (0–1) appears, the threshold that decides solid-vs-gone. Nudge it up if stray fringe pixels linger, down if solid edges are being eaten.
Blend modes
Next to Alpha is a Blend dropdown: how the surface mixes with whatever is already drawn behind it. Alpha decides where the surface shows; Blend decides how its colour combines. The same five modes are available on particle emitters.
| Mode | Use it for |
|---|---|
| Normal | The default. Ordinary over-the-top compositing. |
| Additive (glow) | Adds light: fire, light leaks, holograms, lens glints. Never darkens. |
| Multiply (ink) | Darkens only: ink washes, watercolour, stains, grime, tinted shadow. |
| Screen (haze) | Lightens only, gentler than Additive: fog, haze, soft bloom. |
| Subtract (burn) | Burns the backdrop down: scorch marks, bruising, heavy vignettes. |
Anything but Normal makes the surface transparent and stops it writing depth, so it never hides what's behind it. That's what makes the effect work, and it means these surfaces sort by distance like any other transparency, so overlapping ones can flicker in order. Keep them to accents rather than whole walls.