
Spent all day trying to fix how bad mockups look on black shirts. Still looks off to me. What am I missing? (Free tool)
I’ve been building an in-browser mockup generator for apparel (dizzzign.com), and dark shirts have been driving me crazy.
Every automated generator online looks fine on a clean white tee, but the moment you put a graphic on black, red, or dark navy, it immediately looks fake. You usually get that ugly white box outline around transparent PNGs, or the design looks like a flat sticker pasted on top with zero fabric lighting.
I spent most of today overhauling the rendering engine to tackle this:
- Fixed the white box / halo issue: Clipped the shading layers strictly to the graphic's alpha channel so dark fabric colors stop creating a weird fog around the design.
- Normal map warping: Replaced the basic 2D displacement with surface normal maps and smoothing so prints curve around chest folds and sleeve wrinkles instead of just getting pixel-distorted.
- Print presets: Added options to simulate DTG absorption, heavy opaque screen print ink, and washed-out vintage prints.
- Multi-graphic support + UI overhaul: Put tools on a floating dock so the canvas doesn't feel cluttered, and fixed the mouse tracking bug where dragging artwork would freeze if your cursor left the box.
Here’s the problem though: even with the highlights and normal mapping, dark garments still don't look quite right to me. It's missing that authentic heavy plastisol / white underbase texture you get on a real heavyweight black hoodie or tee.
If you design merch or run a clothing brand, what’s the main thing that immediately gives away a fake mockup on a dark shirt for you? Is it the fabric weave texture not showing through, the highlight reflections, or something with the fold contrast?
Drop your thoughts or harsh feedback, would appreciate an extra pair of eyes on this.