HC/init.lua
2012-10-09 00:50:46 +02:00

299 lines
8.4 KiB
Lua

--[[
Copyright (c) 2011 Matthias Richter
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
Except as contained in this notice, the name(s) of the above copyright holders
shall not be used in advertising or otherwise to promote the sale, use or
other dealings in this Software without prior written authorization.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
]]--
local _NAME = (...)
if not (common and common.class and common.instance) then
class_commons = true
require(_NAME .. '.class')
end
local Shapes = require(_NAME .. '.shapes')
local Spatialhash = require(_NAME .. '.spatialhash')
local newPolygonShape = Shapes.newPolygonShape
local newCircleShape = Shapes.newCircleShape
local newPointShape = Shapes.newPointShape
local function __NULL__() end
local HC = {}
function HC:init(cell_size, callback_collide, callback_stop)
self._active_shapes = {}
self._passive_shapes = {}
self._ghost_shapes = {}
self.groups = {}
self._colliding_only_last_frame = {}
self.on_collide = callback_collide or __NULL__
self.on_stop = callback_stop or __NULL__
self._hash = common.instance(Spatialhash, cell_size)
end
function HC:clear()
self._active_shapes = {}
self._passive_shapes = {}
self._ghost_shapes = {}
self.groups = {}
self._colliding_only_last_frame = {}
self._hash = common.instance(Spatialhash, self._hash.cell_size)
return self
end
function HC:setCallbacks(collide, stop)
if type(collide) == "table" and not (getmetatable(collide) or {}).__call then
stop = collide.stop
collide = collide.collide
end
if collide then
assert(type(collide) == "function" or (getmetatable(collide) or {}).__call,
"collision callback must be a function or callable table")
self.on_collide = collide
end
if stop then
assert(type(stop) == "function" or (getmetatable(stop) or {}).__call,
"stop callback must be a function or callable table")
self.on_stop = stop
end
return self
end
function HC:addShape(shape)
assert(shape.bbox and shape.collidesWith,
"Cannot add custom shape: Incompatible shape.")
self._active_shapes[shape] = shape
self._hash:insert(shape, shape:bbox())
shape._groups = {}
local hash = self._hash
local move, rotate,scale = shape.move, shape.rotate, shape.scale
for _, func in ipairs{'move', 'rotate', 'scale'} do
local old_func = shape[func]
shape[func] = function(self, ...)
local x1,y1,x2,y2 = self:bbox()
old_func(self, ...)
local x3,y3,x4,y4 = self:bbox()
hash:update(self, x1,y1, x2,y2, x3,y3, x4,y4)
end
end
function shape:neighbors()
local neighbors = hash:inRange(self:bbox())
rawset(neighbors, self, nil)
return neighbors
end
function shape:_removeFromHash()
return hash:remove(shape, self:bbox())
end
return shape
end
function HC:activeShapes()
return pairs(self._active_shapes)
end
function HC:shapesInRange(x1,y1, x2,y2)
return self._hash:inRange(x1,y1, x2,y2)
end
function HC:addPolygon(...)
return self:addShape(newPolygonShape(...))
end
function HC:addRectangle(x,y,w,h)
return self:addPolygon(x,y, x+w,y, x+w,y+h, x,y+h)
end
function HC:addCircle(cx, cy, radius)
return self:addShape(newCircleShape(cx,cy, radius))
end
function HC:addPoint(x,y)
return self:addShape(newPointShape(x,y))
end
function HC:share_group(shape, other)
for name,group in pairs(shape._groups) do
if group[other] then return true end
end
return false
end
-- check for collisions
function HC:update(dt)
-- cache for tested/colliding shapes
local tested, colliding = {}, {}
local function may_skip_test(shape, other)
return (shape == other)
or (tested[other] and tested[other][shape])
or self._ghost_shapes[other]
or self:share_group(shape, other)
end
-- collect active shapes. necessary, because a callback might add shapes to
-- _active_shapes, which will lead to undefined behavior (=random crashes) in
-- next()
local active = {}
for shape in self:activeShapes() do
active[shape] = shape
end
local only_last_frame = self._colliding_only_last_frame
for shape in pairs(active) do
tested[shape] = {}
for other in self._hash:rangeIter(shape:bbox()) do
if not self._active_shapes[shape] then
-- break out of this loop is shape was removed in a callback
break
end
if not may_skip_test(shape, other) then
local collide, sx,sy = shape:collidesWith(other)
if collide then
if not colliding[shape] then colliding[shape] = {} end
colliding[shape][other] = {sx, sy}
-- flag shape colliding this frame and call collision callback
if only_last_frame[shape] then
only_last_frame[shape][other] = nil
end
self.on_collide(dt, shape, other, sx, sy)
end
tested[shape][other] = true
end
end
end
-- call stop callback on shapes that do not collide anymore
for a,reg in pairs(only_last_frame) do
for b, info in pairs(reg) do
self.on_stop(dt, a, b, info[1], info[2])
end
end
self._colliding_only_last_frame = colliding
end
-- get list of shapes at point (x,y)
function HC:shapesAt(x, y)
local shapes = {}
for s in pairs(self._hash:cellAt(x,y)) do
if s:contains(x,y) then
shapes[#shapes+1] = s
end
end
return shapes
end
-- remove shape from internal tables and the hash
function HC:remove(shape, ...)
if not shape then return end
self._active_shapes[shape] = nil
self._passive_shapes[shape] = nil
self._ghost_shapes[shape] = nil
shape:_removeFromHash()
return self:remove(...)
end
-- group support
function HC:addToGroup(group, shape, ...)
if not shape then return end
assert(self._active_shapes[shape] or self._passive_shapes[shape],
"Shape is not registered with HC")
if not self.groups[group] then self.groups[group] = {} end
self.groups[group][shape] = true
shape._groups[group] = self.groups[group]
return self:addToGroup(group, ...)
end
function HC:removeFromGroup(group, shape, ...)
if not shape or not self.groups[group] then return end
assert(self._active_shapes[shape] or self._passive_shapes[shape],
"Shape is not registered with HC")
self.groups[group][shape] = nil
shape._groups[group] = nil
return self:removeFromGroup(group, ...)
end
function HC:setPassive(shape, ...)
if not shape then return end
if not self._ghost_shapes[shape] then
assert(self._active_shapes[shape], "Shape is not active")
self._active_shapes[shape] = nil
self._passive_shapes[shape] = shape
end
return self:setPassive(...)
end
function HC:setActive(shape, ...)
if not shape then return end
if not self._ghost_shapes[shape] then
assert(self._passive_shapes[shape], "Shape is not passive")
self._active_shapes[shape] = shape
self._passive_shapes[shape] = nil
end
return self:setActive(...)
end
function HC:setGhost(shape, ...)
if not shape then return end
assert(self._active_shapes[shape] or self._passive_shapes[shape],
"Shape is not registered with HC")
self._active_shapes[shape] = nil
-- dont remove from passive shapes, see below
self._ghost_shapes[shape] = shape
return self:setGhost(...)
end
function HC:setSolid(shape, ...)
if not shape then return end
assert(self._ghost_shapes[shape], "Shape not a ghost")
-- re-register shape. passive shapes were not unregistered above, so if a shape
-- is not passive, it must be registered as active again.
if not self._passive_shapes[shape] then
self._active_shapes[shape] = shape
end
self._ghost_shapes[shape] = nil
return self:setSolid(...)
end
-- the module
HC = common.class("HardonCollider", HC)
local function new(...)
return common.instance(HC, ...)
end
return setmetatable({HardonCollider = HC, new = new},
{__call = function(_,...) return new(...) end})