SOMEONE ONE-SHOTTED A FULL 3D SANDCASTLE SIMULATOR WITH OPUS 5
no game engine, no libraries, no asset files. just one webgl context and about 7,000 lines of code
the sand actually behaves like sand:
> dry sand refuses to hold a slope past 33 degrees, so it just slumps into a cone
> wet it and the water bridges the grains, so you can build past vertical
> soak it too much and the bridges join up and it runs like soup
> pat it down and it compacts, and packing doesnt evaporate, so a tower you mould at noon is still standing at the same height when its bone dry
sand is conserved to the grain. digging fills your pail, pouring empties it
when you pour, its not editing the ground either. tens of thousands of gpu simulated grains actually arc through the air, fall, and only raise the ground where they land
then theres a tide. waves undermine the base of your walls and things collapse on their own, nothing is scripted. a moat spends a wave, a packed berm turns one
it ships with 9 different art styles, from photoreal to woodblock print to a survey map with contour lines drawn straight off the terrain
and crabs. 11 of them wander the beach, walk sideways, climb over ramparts you just built, and bolt if you bring a tool near them
that one prompt ran 7 hours 47 minutes in one sitting, 2,596 turns, 1,680 tool calls, and 943 million tokens
its open source and free to play in your browser
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