Additive Blend (Additive Blend / Additive Synthesis / Blend One One)

Additive Blend (Additive blend / Additive synthesis / Blend One One) is a technical term that is extremely important in rendering and optimization of game graphics (technical art). In translucent drawing, this is a mode in which the new pixel color is simply added (A + B) to the background color to synthesize it, and the more it overlaps, the brighter it becomes and the more it becomes blown out, an essential technology for expressing energy such as shining flames, lasers, and sparks.

Real-world analogy: Dozens of people shine colored flashlight light (additive light) at the same spot in a dark room, and the center where the lights overlap shines dazzlingly pure white.

Additive Blend is a "light addition system that purely adds (+)" the brightness of the new effect to the brightness of the background pixels that have already been painted. With this blend, as the effects overlap, the value rapidly increases toward 1.0 (maximum pure white), so the center of the explosion and the laser core emit a beautiful, bright white light that truly burns your retinas. In addition, since the "black background part" of the image material has a value of zero (0.0), the addition will not affect the background at all, and it will automatically pass through beautifully as a completely transparent margin.

Detailed mechanism and operating principle

Change the material's blend setting to "Additive" (specify `Blend One One` in the shader code) to saturate the light by purely adding the colors between the pixels.