Fixed issue with camera helper if window width and height is zero

Author: britzl

orthographic/render/helper.lua

@@ -2,7 +2,7 @@ local camera = require "orthographic.camera"
 
 if sys.get_config("script.shared_state") ~= "1" then
 	error("ERROR - camera - 'shared_state' setting in game.project must be enabled for camera to work.")
-end	
+end
 
 local M = {}
 
@@ -14,6 +14,7 @@ local SET_CAMERA_OFFSET = hash("set_camera_offset")
 local world_view = vmath.matrix4()
 local world_projection = vmath.matrix4()
 local screen_view = vmath.matrix4()
+local screen_projection = vmath.matrix4()
 local camera_offset = nil
 
 
@@ -41,19 +42,22 @@ end
 function M.screen_projection()
 	local current_window_width = render.get_window_width()
 	local current_window_height = render.get_window_height()
-	local left, right, bottom, top
-	if camera_offset then
-		left = camera_offset.x
-		right = left + current_window_width
-		bottom = camera_offset.y
-		top = bottom + current_window_height
-	else
-		left = 0
-		right = current_window_width
-		bottom = 0
-		top = current_window_height
+	if current_window_width ~= 0 and current_window_height ~= 0 then
+		local left, right, bottom, top
+		if camera_offset then
+			left = camera_offset.x
+			right = left + current_window_width
+			bottom = camera_offset.y
+			top = bottom + current_window_height
+		else
+			left = 0
+			right = current_window_width
+			bottom = 0
+			top = current_window_height
+		end
+		screen_projection = vmath.matrix4_orthographic(left, right, bottom, top, -1, 1)
 	end
-	return vmath.matrix4_orthographic(left, right, bottom, top, -1, 1)
+	return screen_projection
 end
 
 function M.set_screen_view_projection()
@@ -71,4 +75,4 @@ function M.on_message(_, message_id, message)
 	end
 end
 
-return M
+return M