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@@ -53,3 +53,56 @@ there are two ways to do this
 - move the background image appropriately with the view tool
    #+attr_html: :width 600px
    [[./../../_share/media/img/albert/section04/lesson-01/fig05.png]]
+
+** stretching the viewport
+- used if the window needs to be resized or sized differently for a differnt device (ie tablet vs iphone vs iphone11 vs android, etc)
+- disabled by default
+
+- go to Project->Project Settings->Display->Window->Stretch
+
+*** Stretch -> Mode
+
+**** there are two types of stretch modes
+
+1. canvas_items
+2. viewport
+
+**** convas_items
+- albert prefers this
+- renders game initially at set resolution
+- stretches that onto the window
+- can cause blurring with pixel art
+- higher performance (hence faster)
+
+**** viewport
+- looks at actual resolution
+- builds graphics to fit that resolution
+- slower but crisp with pixel art
+
+
+
+*** Stretch -> Aspect
+set aspect to keep
+
+**** there are a bunch of aspect types
+- ignore
+- keep
+- keep width
+- keep height
+
+**** keep
+- keeps the full aspect ration
+- extra space will be filled with black
+
+*** how to deal with black bars
+- make artwork that accounts for it
+- e.g. put a fence around the boundary
+
+** window size
+- if the ratios set for viewport are too small you can directly set the window size
+
+*** go to
+1. Click on 'Advanced Settings'
+2. Project->Project Settings->Display->Window->Size
+4. scroll down to "Window Width Override" and "Window Height Override"
+5. you can perform calculation sin the textboxes