Added collision detection and pause on crash

[lightcycles-love.git] / scene.lua

diff --git a/scene.lua b/scene.lua
index 0ccc1a3f3c067555853051c0393a4e589a1549cd..84c4473e1b91d523bf11356a24b8b209e009e3b7 100644 (file)
--- a/scene.lua
+++ b/scene.lua
@@ -5,6 +5,7 @@ require 'player'
 
 
 scene = {}
+scene.paused = false
 scene.width = love.graphics.getWidth()
 scene.height = love.graphics.getHeight()
 scene.players = {}
@@ -15,24 +16,8 @@ scene.grid.delta = 50
 
 -- load
 function scene:load()
-    table.insert(scene.players, Player:new({
-        position=vec2:new(100,100),
-        vector=Player.vectors.right,
-        path={},
-        }))
-
-    table.insert(scene.players, Player:new({
-        position=vec2:new(self.width-100,self.height-100),
-        vector=Player.vectors.left,
-        path={},
-        color={255, 255, 0},
-        keys={
-            up='up',
-            down='down',
-            left='left',
-            right='right',
-            }
-        }))
+    table.insert(scene.players, require('players/1'))
+    --table.insert(scene.players, require('players/2'))
 end
 
 -- draw
@@ -57,6 +42,12 @@ end
 function scene:draw()
     self:drawGrid()
     self:drawPlayers()
+
+    -- draw intersection if it's there
+    if self.intersection then
+        love.graphics.setColor(0, 255, 0)
+        love.graphics.line(self.intersection)
+    end
 end
 
 -- update
@@ -66,13 +57,80 @@ function scene:updatePlayers(dt)
     end
 end
 
+function doLinesIntersect(x1, y1, x2, y2, x3, y3, x4, y4)
+    if x1 == x2 and x3 == x4
+    or y1 == y2 and y3 == y4
+    then
+        -- if lines are parallel, no intersection!
+        return false
+    else
+        -- if lines are not parallel, they must intersect
+        -- do segments overlap?
+        if
+            x1 <= x3 and x3 <= x2
+        and y1 <= y3 and y3 <= y2
+        or
+            x3 <= x1 and x1 <= x4
+        and y3 <= y1 and y1 <= y4
+        then
+            scene.paused = true
+            scene.intersection = {x1, y1, x2, y2, x3, y3, x4, y4}
+            return true
+        end
+    end
+end
+
+function doesLineIntersectPlayerPaths(path, x1, y1, x2, y2)
+    local stash = {}
+    -- for every line in path,
+    -- check intersection with player line
+    for k,v in pairs(path) do
+        if #stash == 4 then
+            if doLinesIntersect(x1, y1, x2, y2, stash[4], stash[3], stash[2], stash[1]) then
+                return true
+            end
+            stash = {}
+        else
+            table.insert(stash,v)
+        end
+    end
+    return false
+end
+
+-- love collision handler
+function collision(player)
+    print('Player '..tostring(player)..' crashed!')
+    --love.event.quit()
+end
+love.handlers.collision = collision
+
+function scene:handleCollisions()
+    -- calculate the last line for each player from current position
+    -- check if line intersects any other path line
+    -- if so, raise collision event for player
+    for _,player in pairs(self.players) do
+        local x1 = player.path[#player.path-1]
+        local y1 = player.path[#player.path]
+        local x2 = player.position.x
+        local y2 = player.position.y
+
+        -- check intersection against each existing path
+        for _,player2 in pairs(self.players) do
+            if doesLineIntersectPlayerPaths(player2.path, x1, y1, x2, y2) then
+                love.event.push('collision', player)
+            end
+        end
+    end
+end
+
 function scene:update(dt)
     self:updatePlayers(dt)
+    self:handleCollisions()
 end
 
 -- quit
 function scene:quit()
-    for i,player in pairs(self.players) do
-        print('Player '..i..' generated '.. #player.path / 2 .. ' path points')
+    for _,player in pairs(self.players) do
+        print(tostring(player)..' generated '.. #player.path / 2 .. ' path points')
     end
 end