Added more borders. Fixed border render issue on edge cases with values equal to threshhold.

map.lua

@@ -42,10 +42,17 @@ function map.draw()
   lg.clear( 0, 0, 0, 1 )
 
   do --territory
+    lg.setColor( 1,1,1,1)
+    lg.setLineJoin( "none" )
+    lg.setLineWidth( 1 / Camera.zoom )
     lg.replaceTransform( Camera.tfTerritory )
     lg.setBlendMode( "add" )
     for k, v in pairs(map.territory) do
-      if v.visible then v:draw() end
+      if v.visible then 
+        v:draw()
+        v:drawBorder( "land" )
+        v:drawBorder( "sea" )
+      end
     end
     if map.sailable.visible then map.sailable:draw() end
     lg.setBlendMode( "alpha" )
@@ -54,10 +61,15 @@ function map.draw()
   end
   
   do --borders
-    lg.setColor( 1,1,1,1)
     lg.setLineJoin( "none" )
     lg.setLineWidth( 1 / Camera.zoom )
-    map.sailable:drawBorder()
+    
+    lg.setColor( 1, 1, 1, 0.5)
+    map.sailable:drawBorder( "sailable" )
+    
+    
+    lg.setColor( 1, 0, 0, 0.5)
+    map.sailable:drawBorder( "placeable" )
   end
 
 

territory.lua

@@ -25,7 +25,11 @@ function t.load( filename, name )
 
   if name == "sailable" then
     t.sailable = territory
-    t.computeBorder( territory, 20 / 255 )
+    t.computeBorder( territory, 20 / 255, "sailable" )
+    t.computeBorder( territory, 60 / 255, "placeable" )
+  else
+    t.computeBorder( territory, 60 / 255, "sea" )
+    t.computeBorder( territory, 130 / 255, "land" )
   end
   return setmetatable( territory, {__index = t } )
 end
@@ -90,17 +94,18 @@ function t.draw( territory )
   lg.draw( territory.img )
 end
 
-function t.drawBorder( territory )
+function t.drawBorder( territory, key )
-  --lg.setColor( territory.colour )
+  key = key or "border"
-  for _, poly in ipairs( territory.border ) do
+  for _, poly in ipairs( territory[key] ) do
     lg.line( poly )
   end
 end
 
 
-function t.computeBorder( territory, threshold )
+function t.computeBorder( territory, threshold, key )
-  territory.border = {}
+  key = key or "border"
-  local border = territory.border
+  territory[key] = {}
+  local border = territory[key]
   local n = 1
 
   for x = 0, 511 do
@@ -112,25 +117,25 @@ function t.computeBorder( territory, threshold )
 
       --Sample image and detect edge:
       local curValue = territory.imgd:getPixel( x, y )
-      local leftValue = territory.imgd:getPixel( math.min( x + 1, 511 ), y )
+      local rightValue = territory.imgd:getPixel( math.min( x + 1, 511 ), y )
       local downValue = territory.imgd:getPixel( x, math.min( 284, y + 1 ) )
 
-      local isLeftEdge =
+      local isRightEdge =
-      ((curValue >= threshold) and (leftValue < threshold)) or
+      ((curValue >= threshold) and (rightValue < threshold)) or
-      ((curValue <= threshold) and (leftValue > threshold))
+      ((curValue < threshold) and (rightValue >= threshold))
       local isDownEdge = 
       ((curValue >= threshold) and (downValue < threshold)) or
-      ((curValue <= threshold) and (downValue > threshold))
+      ((curValue < threshold) and (downValue >= threshold))
 
-      if isLeftEdge then
+      if isRightEdge then
         --print( "Left edge:", brx, bry, trx, try )
-        border[n] = { brx, bry, trx, try }
+        border[n] = { x + 1, y, x + 1, y + 1 }
         n = n + 1
       end
 
       if isDownEdge then
         --print( "Down edge:", blx, bly, brx, bry )
-        border[n] = { blx, bly, brx, bry }
+        border[n] = { x, y + 1, x + 1, y + 1 }
         n = n + 1
       end
     end