X-Git-Url: http://git.purplebirdman.com/lightcycles-love.git/blobdiff_plain/8f054564538fd6e9b63f6d84796710232ba31908..HEAD:/scene.lua

diff --git a/scene.lua b/scene.lua
index 73164e3..4d15993 100644
--- a/scene.lua
+++ b/scene.lua
@@ -5,6 +5,8 @@ require 'player'
 
 
 scene = {}
+scene.debug = false
+scene.paused = false
 scene.width = love.graphics.getWidth()
 scene.height = love.graphics.getHeight()
 scene.players = {}
@@ -24,12 +26,21 @@ function scene:drawGrid()
     love.graphics.setBackgroundColor(self.grid.bgcolor)
     love.graphics.setColor(self.grid.linecolor)
 
+    love.graphics.setLineWidth(2)
     for x=0,self.width,self.grid.delta do
         love.graphics.line(x, 0, x, self.height)
     end
     for y=0,self.height,self.grid.delta do
         love.graphics.line(0, y, self.width, y)
     end
+
+    love.graphics.setLineWidth(0.5)
+    for x=0,self.width,self.grid.delta/2 do
+        love.graphics.line(x, 0, x, self.height)
+    end
+    for y=0,self.height,self.grid.delta/2 do
+        love.graphics.line(0, y, self.width, y)
+    end
 end
 
 function scene:drawPlayers()
@@ -41,6 +52,14 @@ end
 function scene:draw()
     self:drawGrid()
     self:drawPlayers()
+
+    -- draw intersection if it's there
+    if self.debug and self.intersection then
+        love.graphics.setColor(0, 255, 0)
+        love.graphics.line(self.intersection.a)
+        love.graphics.setColor(0, 0, 255)
+        love.graphics.line(self.intersection.b)
+    end
 end
 
 -- update
@@ -50,32 +69,100 @@ function scene:updatePlayers(dt)
     end
 end
 
-function doesLineIntersectPlayerPaths(path, x1, y1, x2, y2)
+function doLinesIntersect(x1,y1, x2,y2, x3,y3, x4,y4)
+    local intersect = false
+
+    if x1 == x2 and x3 == x4
+    or y1 == y2 and y3 == y4
+    then
+        -- if lines are parallel, no intersection!
+    elseif x1 == x2 and y3 == y4 then
+        intersect = (
+                x3 < x1 and x1 < x4
+                or
+                x4 < x1 and x1 < x3
+            ) and (
+                y1 < y3 and y3 < y2
+                or
+                y2 < y3 and y3 < y1
+            )
+    elseif x3 == x4 and y1 == y2 then
+        intersect = (
+                x1 < x3 and x3 < x2
+                or
+                x2 < x3 and x3 < x1
+            ) and (
+                y3 < y1 and y1 < y4
+                or
+                y4 < y1 and y1 < y3
+            )
+    else
+        print('You should never see this message')
+    end
+
+    if intersect then
+        scene.intersection = {
+            a = {x1,y1, x2,y2},
+            b = {x3,y3, x4,y4},
+            }
+    end
+
+    return intersect
+end
+
+function doesLineIntersectPlayerPaths(node, v1, v2)
+    -- for every line in path,
+    -- check intersection with player line
+    while node and node.prev do
+        local v3 = node.vector
+        local v4 = node.prev.vector
+        if doLinesIntersect(v1.x,v1.y, v2.x,v2.y, v3.x,v3.y, v4.x,v4.y) then
+            return true
+        end
+        node = node.prev
+    end
     return false
 end
 
+-- love collision handler
+function collision(player)
+    print(player..' crashed!')
+    scene.paused = true
+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
+    -- only check last line for intersection, since all the rest should be ok
     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
+        local v1 = player.path.vector
+        local v2 = player.path.prev.vector
 
-        -- check intersection against each existing path
+        -- outside boundary
+        if v1.x < 0 or v1.x > love.graphics.getWidth()
+        or v1.y < 0 or v1.y > love.graphics.getHeight()
+        then
+            love.event.push('collision', tostring(player))
+            break
+        end
+
+        -- inside boundary
         for _,player2 in pairs(self.players) do
-            if doesLineIntersectPlayerPaths(player2.path, x1, y1, x2, y2) then
-                love.event.push('collision', player)
+            if doesLineIntersectPlayerPaths(player2.path, v1, v2) then
+                love.event.push('collision', tostring(player))
+                break
             end
         end
     end
 end
 
 function scene:update(dt)
-    self:updatePlayers(dt)
-    self:handleCollisions()
+    if not self.paused then
+        self:updatePlayers(dt)
+        self:handleCollisions()
+    end
 end
 
 -- quit