diff options
Diffstat (limited to 'libs/sti/plugins/box2d.lua')
| -rw-r--r-- | libs/sti/plugins/box2d.lua | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/libs/sti/plugins/box2d.lua b/libs/sti/plugins/box2d.lua new file mode 100644 index 0000000..c6d4148 --- /dev/null +++ b/libs/sti/plugins/box2d.lua @@ -0,0 +1,323 @@ +--- Box2D plugin for STI +-- @module box2d +-- @author Landon Manning +-- @copyright 2019 +-- @license MIT/X11 + +local love = _G.love +local utils = require((...):gsub('plugins.box2d', 'utils')) +local lg = require((...):gsub('plugins.box2d', 'graphics')) + +return { + box2d_LICENSE = "MIT/X11", + box2d_URL = "https://github.com/karai17/Simple-Tiled-Implementation", + box2d_VERSION = "2.3.2.7", + box2d_DESCRIPTION = "Box2D hooks for STI.", + + --- Initialize Box2D physics world. + -- @param world The Box2D world to add objects to. + box2d_init = function(map, world) + assert(love.physics, "To use the Box2D plugin, please enable the love.physics module.") + + local body = love.physics.newBody(world, map.offsetx, map.offsety) + local collision = { + body = body, + } + + local function addObjectToWorld(objshape, vertices, userdata, object) + local shape + + if objshape == "polyline" then + if #vertices == 4 then + shape = love.physics.newEdgeShape(unpack(vertices)) + else + shape = love.physics.newChainShape(false, unpack(vertices)) + end + else + shape = love.physics.newPolygonShape(unpack(vertices)) + end + + local currentBody = body + --dynamic are objects/players etc. + if userdata.properties.dynamic == true then + currentBody = love.physics.newBody(world, map.offsetx, map.offsety, 'dynamic') + -- static means it shouldn't move. Things like walls/ground. + elseif userdata.properties.static == true then + currentBody = love.physics.newBody(world, map.offsetx, map.offsety, 'static') + -- kinematic means that the object is static in the game world but effects other bodies + elseif userdata.properties.kinematic == true then + currentBody = love.physics.newBody(world, map.offsetx, map.offsety, 'kinematic') + end + + local fixture = love.physics.newFixture(currentBody, shape) + fixture:setUserData(userdata) + + -- Set some custom properties from userdata (or use default set by box2d) + fixture:setFriction(userdata.properties.friction or 0.2) + fixture:setRestitution(userdata.properties.restitution or 0.0) + fixture:setSensor(userdata.properties.sensor or false) + fixture:setFilterData( + userdata.properties.categories or 1, + userdata.properties.mask or 65535, + userdata.properties.group or 0 + ) + + local obj = { + object = object, + body = currentBody, + shape = shape, + fixture = fixture, + } + + table.insert(collision, obj) + end + + local function getPolygonVertices(object) + local vertices = {} + for _, vertex in ipairs(object.polygon) do + table.insert(vertices, vertex.x) + table.insert(vertices, vertex.y) + end + + return vertices + end + + local function calculateObjectPosition(object, tile) + local o = { + shape = object.shape, + x = (object.dx or object.x) + map.offsetx, + y = (object.dy or object.y) + map.offsety, + w = object.width, + h = object.height, + polygon = object.polygon or object.polyline or object.ellipse or object.rectangle + } + + local userdata = { + object = o, + properties = object.properties + } + + o.r = object.rotation or 0 + if o.shape == "rectangle" then + local cos = math.cos(math.rad(o.r)) + local sin = math.sin(math.rad(o.r)) + local oy = 0 + + if object.gid then + local tileset = map.tilesets[map.tiles[object.gid].tileset] + local lid = object.gid - tileset.firstgid + local t = {} + + -- This fixes a height issue + o.y = o.y + map.tiles[object.gid].offset.y + oy = o.h + + for _, tt in ipairs(tileset.tiles) do + if tt.id == lid then + t = tt + break + end + end + + if t.objectGroup then + for _, obj in ipairs(t.objectGroup.objects) do + -- Every object in the tile + calculateObjectPosition(obj, object) + end + + return + else + o.w = map.tiles[object.gid].width + o.h = map.tiles[object.gid].height + end + end + + o.polygon = { + { x=o.x+0, y=o.y+0 }, + { x=o.x+o.w, y=o.y+0 }, + { x=o.x+o.w, y=o.y+o.h }, + { x=o.x+0, y=o.y+o.h } + } + + for _, vertex in ipairs(o.polygon) do + vertex.x, vertex.y = utils.rotate_vertex(map, vertex, o.x, o.y, cos, sin, oy) + end + + local vertices = getPolygonVertices(o) + addObjectToWorld(o.shape, vertices, userdata, tile or object) + elseif o.shape == "ellipse" then + if not o.polygon then + o.polygon = utils.convert_ellipse_to_polygon(o.x, o.y, o.w, o.h) + end + local vertices = getPolygonVertices(o) + local triangles = love.math.triangulate(vertices) + + for _, triangle in ipairs(triangles) do + addObjectToWorld(o.shape, triangle, userdata, tile or object) + end + elseif o.shape == "polygon" then + -- Recalculate collision polygons inside tiles + if tile then + local cos = math.cos(math.rad(o.r)) + local sin = math.sin(math.rad(o.r)) + for _, vertex in ipairs(o.polygon) do + vertex.x = vertex.x + o.x + vertex.y = vertex.y + o.y + vertex.x, vertex.y = utils.rotate_vertex(map, vertex, o.x, o.y, cos, sin) + end + end + + local vertices = getPolygonVertices(o) + local triangles = love.math.triangulate(vertices) + + for _, triangle in ipairs(triangles) do + addObjectToWorld(o.shape, triangle, userdata, tile or object) + end + elseif o.shape == "polyline" then + local vertices = getPolygonVertices(o) + addObjectToWorld(o.shape, vertices, userdata, tile or object) + end + end + + for _, tile in pairs(map.tiles) do + if map.tileInstances[tile.gid] then + for _, instance in ipairs(map.tileInstances[tile.gid]) do + -- Every object in every instance of a tile + if tile.objectGroup then + for _, object in ipairs(tile.objectGroup.objects) do + if object.properties.collidable == true then + object = utils.deepCopy(object) + object.dx = instance.x + object.x + object.dy = instance.y + object.y + calculateObjectPosition(object, instance) + end + end + end + + -- Every instance of a tile + if tile.properties.collidable == true then + local object = { + shape = "rectangle", + x = instance.x, + y = instance.y, + width = map.tilewidth, + height = map.tileheight, + properties = tile.properties + } + + calculateObjectPosition(object, instance) + end + end + end + end + + for _, layer in ipairs(map.layers) do + -- Entire layer + if layer.properties.collidable == true then + if layer.type == "tilelayer" then + for gid, tiles in pairs(map.tileInstances) do + local tile = map.tiles[gid] + local tileset = map.tilesets[tile.tileset] + + for _, instance in ipairs(tiles) do + if instance.layer == layer then + local object = { + shape = "rectangle", + x = instance.x, + y = instance.y, + width = tileset.tilewidth, + height = tileset.tileheight, + properties = tile.properties + } + + calculateObjectPosition(object, instance) + end + end + end + elseif layer.type == "objectgroup" then + for _, object in ipairs(layer.objects) do + calculateObjectPosition(object) + end + elseif layer.type == "imagelayer" then + local object = { + shape = "rectangle", + x = layer.x or 0, + y = layer.y or 0, + width = layer.width, + height = layer.height, + properties = layer.properties + } + + calculateObjectPosition(object) + end + end + + -- Individual objects + if layer.type == "objectgroup" then + for _, object in ipairs(layer.objects) do + if object.properties.collidable == true then + calculateObjectPosition(object) + end + end + end + end + + map.box2d_collision = collision + end, + + --- Remove Box2D fixtures and shapes from world. + -- @param index The index or name of the layer being removed + box2d_removeLayer = function(map, index) + local layer = assert(map.layers[index], "Layer not found: " .. index) + local collision = map.box2d_collision + + -- Remove collision objects + for i = #collision, 1, -1 do + local obj = collision[i] + + if obj.object.layer == layer then + obj.fixture:destroy() + table.remove(collision, i) + end + end + end, + + --- Draw Box2D physics world. + -- @param tx Translate on X + -- @param ty Translate on Y + -- @param sx Scale on X + -- @param sy Scale on Y + box2d_draw = function(map, tx, ty, sx, sy) + local collision = map.box2d_collision + + lg.push() + lg.scale(sx or 1, sy or sx or 1) + lg.translate(math.floor(tx or 0), math.floor(ty or 0)) + + for _, obj in ipairs(collision) do + local points = {obj.body:getWorldPoints(obj.shape:getPoints())} + local shape_type = obj.shape:getType() + + if shape_type == "edge" or shape_type == "chain" then + love.graphics.line(points) + elseif shape_type == "polygon" then + love.graphics.polygon("line", points) + else + error("sti box2d plugin does not support "..shape_type.." shapes") + end + end + + lg.pop() + end +} + +--- Custom Properties in Tiled are used to tell this plugin what to do. +-- @table Properties +-- @field collidable set to true, can be used on any Layer, Tile, or Object +-- @field sensor set to true, can be used on any Tile or Object that is also collidable +-- @field dynamic set to true, can be used on any Tile or Object +-- @field friction can be used to define the friction of any Object +-- @field restitution can be used to define the restitution of any Object +-- @field categories can be used to set the filter Category of any Object +-- @field mask can be used to set the filter Mask of any Object +-- @field group can be used to set the filter Group of any Object |