Drop anywhere

Mode	What it does
As stored	Use the blue channel exactly as it is in the file. Default -- correct for ordinary RGB tangent-space normal maps.
RG → RGB	Convert an RG/BC5 (ATI2/3Dc) map to RGB: ignore stored blue and compute Z = sqrt(1 - R² - G²) instead, the same way a shader reconstructs it at runtime. X/Y are left untouched.
RGB → RG	Convert an RGB map to RG/BC5-style: force blue to black without touching X/Y, so it round-trips cleanly back through "RG → RGB". Useful to preview/export what this map looks like before compressing it to BC5.

TGA, TIFF, and PSD import — previously unsupported, now decoded client-side (tga-js, UTIF + pako, ag-psd).
PSD layer picker — choose the flattened composite, or select individual layers to merge (All / Visible only / None, with an optional trim-to-opaque-pixels toggle).
Smart normal-map detection — on load, a heuristic checks the image and warns (via toast) if it looks like an RG/BC5 map, a photo, grayscale art, or otherwise not a normal map.

OpenGL (+Y) / DirectX (-Y) standard toggle — picking a standard changes how rotation is processed (correct handedness for the target engine), not an immediate flip of the image. A reference table (help icon) lists the convention used by 20+ engines and renderers.
Auto-detected DirectX standard — scans uploaded files for authoring-tool signatures (e.g. DirectXTex) and switches the standard automatically when found.
Blue channel modes — "As stored," "RG → RGB" (reconstruct Z from X/Y for BC5-style maps), and "RGB → RG" (force blue to black, round-trips cleanly). Help icon explains each mode.
Fixed rotation jaggies — the rotation shader now correctly un/premultiplies alpha, so anti-aliased edges rotate smoothly instead of fringing.
Fixed export scaling — downloaded PNGs are now pixel-exact 1:1 with the source image (previously inflated by display DPI scaling).

Full visual redesign: dark theme, consistent tokens, toggle switches, and the OpenGL/DirectX control styled to match a shared design system.
Rotation knob's background now stays static while only the indicator spins (previously the whole dial visibly rotated), and the indicator now ends in a grab-handle-style dot.
Click the knob's center readout to jump straight to editing the angle by hand.
Fixed a bug where dragging the knob after a programmatic reset would jump from the pre-reset angle.
Reset controls trimmed down to just Vector Strength, which only appears once it's off its default (1.0); the strength slider also marks its zero value with a notch.
Toast notification system for non-blocking warnings/info.

[ or drop/paste normal map ]

0°

Normal map standard:

Snap to degree:

0 1 5 15 45 90

Flip:

None Depth

Blue channel:

As source RG → RGB RGB → RG

Vector strength:1.0

Rotate vectors only

Throttle updates

New filename:

Normal Map Standards by Software

Blue Channel Options