just playing around with a few things, narrowed down my last issues with scaling and translation just need to figure out a workaround

examples/short.lua

@@ -92,11 +92,8 @@ function love.draw()
 end
 
 function drawBackground(l,t,w,h)
-  love.graphics.push()
-    love.graphics.origin()
   love.graphics.setColor(255, 255, 255)
-    love.graphics.rectangle("fill", 0, 0, w, h)
-  love.graphics.pop()
+  love.graphics.rectangle("fill", -l, -t, w, h)
 end
 
 function drawForground(l,t,w,h)

lib/light.lua

@@ -125,7 +125,10 @@ function light:setGlowStrength(strength)
 end
 
 function light:inRange(l,t,w,h)
-  return self.x + self.range > l and self.x - self.range < (l+w) and self.y + self.range > t and self.y - self.range < (t+h)
+  return self.x + self.range > l     and 
+         self.x - self.range < (l+w) and 
+         self.y + self.range > t     and 
+         self.y - self.range < (t+h)
 end
 
 function light:drawShadow(l,t,w,h,s,bodies, canvas)
@@ -153,7 +156,7 @@ function light:drawShadow(l,t,w,h,s,bodies, canvas)
       love.graphics.setShader(self.shader)
       love.graphics.setInvertedStencil(stencils.shadow(shadow_geometry, bodies))
       love.graphics.setBlendMode("additive")
-      love.graphics.rectangle("fill", l,t,w,h)
+      love.graphics.rectangle("fill", -l,-t,w,h)
 
       -- draw color shadows
       love.graphics.setBlendMode("multiplicative")
@@ -174,13 +177,13 @@ function light:drawShadow(l,t,w,h,s,bodies, canvas)
       end
     end)
 
-    -- draw shine
+    -- update shine
     util.drawto(self.shine, l, t, s, function()
       love.graphics.setShader(self.shader)
       self.shine:clear(255, 255, 255)
       love.graphics.setBlendMode("alpha")
       love.graphics.setStencil(stencils.colorShadow(bodies))
-      love.graphics.rectangle("fill", 0,0,w,h)
+      love.graphics.rectangle("fill", -l,-t,w,h)
     end)
 
     love.graphics.setStencil()

lib/light_world.lua

@@ -96,7 +96,6 @@ end
 function light_world:draw(l,t,s)
   l,t,s = (l or 0), (t or 0), s or 1 
   local w, h = love.graphics.getWidth(), love.graphics.getHeight()
-
   util.drawto(self.render_buffer, l, t, s, function()
     self.drawBackground( l,t,w,h,s)
     self:drawShadow(     l,t,w,h,s)