Flyweight Pattern

Shares common, immutable state across many fine-grained objects to dramatically reduce memory usage when dealing with huge numbers of similar objects.

#structural#flyweight#memory#sharing#pool#gof

Field Note - Real-world Analogy

Think of it like this

“Like characters in a word processor. The character "A" appears thousands of times in a document, but the font, size, and glyph data for "A" is only stored once — that's the flyweight (intrinsic state). Each occurrence of "A" just stores its position on the page — that's the extrinsic state. The glyph is shared; the position is unique.”

Field Observations - Key Topics Covered

The problem: you're building a forest renderer that places 1 million tree objects on screen. Each tree stores its type name, color, texture, X position, and Y position. If all those million trees share the same type/color/texture data (because it's a pine forest), you're storing those large textures in memory 1 million times — an obvious waste.

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