45 lines
1.5 KiB
Lua
45 lines
1.5 KiB
Lua
local world = require("world")
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local band = bit.band
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local collidingEntities = world:filteredSystem("collidingEntitites", {
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position = T.XyPair,
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size = T.XyPair,
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canCollideWith = T.BitMask,
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isSolid = Maybe(T.bool),
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})
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local function intersects(rect, rectOther)
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local left = rect.position.x
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local right = rect.position.x + rect.size.x
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local top = rect.position.y
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local bottom = rect.position.y + rect.size.y
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local leftOther = rectOther.position.x
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local rightOther = rectOther.position.x + rectOther.size.x
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local topOther = rectOther.position.y
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local bottomOther = rectOther.position.y + rectOther.size.y
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return leftOther < right and left < rightOther and topOther < bottom and top < bottomOther
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end
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world:filteredSystem(
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"collisionDetection",
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{ position = T.XyPair, size = T.XyPair, canBeCollidedBy = T.BitMask, isSolid = Maybe(T.bool) },
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-- Here, the entity, e, refers to some entity that a moving object may be colliding *into*
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function(e, _, system)
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for _, collider in pairs(collidingEntities.entities) do
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if
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(e ~= collider)
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and collider.canCollideWith
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and e.canBeCollidedBy
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and band(collider.canCollideWith, e.canBeCollidedBy) ~= 0
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and intersects(e, collider)
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then
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system.world:addEntity({
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collisionBetween = { collider = collider, collidedInto = e },
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})
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end
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end
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end
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)
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