Squashed 'l1/' content from commit 670aa58

git-subtree-dir: l1
git-subtree-split: 670aa582df99e87fca7c247b949baf452e8c234f

sexp_effects/effects/mirror.sexp

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+;; Mirror effect - mirrors half of image
+(require-primitives "geometry" "image")
+
+(define-effect mirror
+  :params (
+    (mode :type string :default "left_right")
+  )
+  (let* ((w (image:width frame))
+         (h (image:height frame))
+         (hw (floor (/ w 2)))
+         (hh (floor (/ h 2))))
+    (cond
+      ((= mode "left_right")
+       (let ((left (image:crop frame 0 0 hw h))
+             (result (copy frame)))
+         (paste result (geometry:flip-img left "horizontal") hw 0)))
+
+      ((= mode "right_left")
+       (let ((right (image:crop frame hw 0 hw h))
+             (result (copy frame)))
+         (paste result (geometry:flip-img right "horizontal") 0 0)))
+
+      ((= mode "top_bottom")
+       (let ((top (image:crop frame 0 0 w hh))
+             (result (copy frame)))
+         (paste result (geometry:flip-img top "vertical") 0 hh)))
+
+      ((= mode "bottom_top")
+       (let ((bottom (image:crop frame 0 hh w hh))
+             (result (copy frame)))
+         (paste result (geometry:flip-img bottom "vertical") 0 0)))
+
+      (else frame))))