unmaintained: New home for misfit Factor vocabularies.

[factor-unmaintained.git] / images / processing / rotation / rotation.factor

diff --git a/images/processing/rotation/rotation.factor b/images/processing/rotation/rotation.factor
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+! Copyright (C) 2009 Kobi Lurie.
+! See http://factorcode.org/license.txt for BSD license.
+USING: accessors arrays colors combinators
+combinators.short-circuit fry grouping images images.bitmap
+images.loader images.normalization kernel locals math sequences ;
+IN: images.processing.rotation
+
+ERROR: unsupported-rotation degrees ;
+
+<PRIVATE
+
+: rotate-90 ( seq^3 -- seq^3 ) flip [ reverse ] map ;
+: rotate-180 ( seq^3 -- seq^3 ) reverse [ reverse ] map ;
+: rotate-270 ( seq^3 -- seq^3 ) flip reverse ;
+
+: (rotate) ( seq n -- seq' )
+    {
+        { 0 [ ] }
+        { 90 [ rotate-90 ] }
+        { 180 [ rotate-180 ] }
+        { 270 [ rotate-270 ] }
+        [ unsupported-rotation ]
+    } case ;
+
+: rows-remove-pad ( byte-rows -- pixels' )
+    [ dup length 4 mod head* ] map ; 
+
+: row-length ( image -- n ) 
+    [ bitmap>> length ] [ dim>> second ] bi /i ;
+
+: image>byte-rows ( image -- byte-rows )
+    [ bitmap>> ] [ row-length ] bi group rows-remove-pad ;
+
+: (seperate-to-pixels) ( byte-rows image -- pixel-rows )
+    component-order>> bytes-per-pixel '[ _ group ] map ;
+
+: image>pixel-rows ( image -- pixel-rows )
+    [ image>byte-rows ] keep (seperate-to-pixels) ;
+ 
+: flatten-table ( seq^3 -- seq )
+    [ concat ] map concat ;
+
+: ?reverse-dimensions ( image n -- )
+    { 270 90 } member? [ [ reverse ] change-dim ] when drop ;
+
+:  normalize-degree ( n -- n' ) 360 rem ;
+
+: processing-effect ( image quot -- image' )
+    '[ image>pixel-rows @ flatten-table ] [ bitmap<< ] [ ] tri ; inline
+
+:: rotate' ( image n -- image )
+    n normalize-degree :> n'
+    image image>pixel-rows :> pixel-table
+    image n' ?reverse-dimensions
+    pixel-table n' (rotate) :> table-rotated
+    image table-rotated flatten-table >>bitmap ;
+
+PRIVATE>
+
+: rotate ( image n -- image' )
+    normalize-degree
+    [ '[ _ (rotate) ] processing-effect ] [ ?reverse-dimensions ] 2bi ;
+
+: reflect-y-axis ( image -- image ) 
+    [ [ reverse ] map ] processing-effect ;
+
+: reflect-x-axis ( image -- image ) 
+    [ reverse ] processing-effect ;