Forward Rendering
Shade each fragment per light, in one pass
Definition
Forward rendering shades each visible fragment against every active light in a single pass. It is simple, MSAA-friendly, and cheap when light counts are low — which is why it is the default in URP and Unreal’s forward mode. The downside is cost scaling: ten dynamic lights touching one object means ten shading evaluations per pixel, so heavy multi-light scenes prefer deferred rendering instead.
In production
Forward rendering shades each visible fragment against every active light in a single pass, evaluating the full lighting equation per-pixel per-light without an intermediate G-Buffer, which is why it's the default in Unity's URP and available as Unreal's Forward Shading mode. It is simple, MSAA-friendly (since there's no deferred resolve step blocking hardware multisampling), and cheap when light counts stay low — a typical mobile or VR scene budgets 1-4 dynamic lights per object to stay within this model's sweet spot. The downside is cost scaling with both light count and overdraw: ten dynamic lights touching one object means ten full shading evaluations per pixel, so dense scenes with many overlapping dynamic lights get expensive fast. Unreal's Forward Shading mode is specifically recommended for VR projects because it enables true hardware MSAA, which looks noticeably cleaner than TAA on the stereo, high-FOV views VR headsets produce.
