Added line intersection highlights

[lightcycles-love.git] / scene.lua

diff --git a/scene.lua b/scene.lua
index 73164e335115a455e7f799ecb5059298b1726d7d..f11fc3e53cf3e740968c1487e5c6b58f48f9d99f 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 = {}
@@ -16,7 +17,7 @@ scene.grid.delta = 50
 -- load
 function scene:load()
     table.insert(scene.players, require('players/1'))
-    table.insert(scene.players, require('players/2'))
+    --table.insert(scene.players, require('players/2'))
 end
 
 -- draw
@@ -41,6 +42,14 @@ 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.a)
+        love.graphics.setColor(0, 0, 255)
+        love.graphics.line(self.intersection.b)
+    end
 end
 
 -- update
@@ -50,10 +59,60 @@ function scene:updatePlayers(dt)
     end
 end
 
-function doesLineIntersectPlayerPaths(path, x1, y1, x2, y2)
+function doLinesIntersect(x1,y1, x2,y2, x3,y3, x4,y4)
+    scene.intersection = {
+        a = {x1,y1, x2,y2},
+        b = {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
+            return true
+        end
+    end
+end
+
+function doesLineIntersectPlayerPaths(path, x1,y1, x2,y2)
+    local cache = {}
+    cache.a = {}
+    cache.b = {}
+    -- for every line in path,
+    -- check intersection with player line
+    for k,v in pairs(path) do
+        if #cache.a == 2 then
+            if #cache.b == 2 then
+                if doLinesIntersect(x1,y1, x2,y2, cache.a[1],cache.a[2], cache.b[1],cache.b[2]) then
+                    return true
+                end
+            end
+            cache.b = cache.a
+            cache.a = {}
+        end
+        table.insert(cache.a,v)
+    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