use radix literals

[factor.git] / extra / images / gif / gif.factor

diff --git a/extra/images/gif/gif.factor b/extra/images/gif/gif.factor
index 4744f55a6baeaba1e7566a400348e493948dc7c8..acdb5687e776e9f9e84b4c6d9209a13f79e41de2 100644 (file)
--- a/extra/images/gif/gif.factor
+++ b/extra/images/gif/gif.factor
@@ -1,11 +1,9 @@
-! Copyrigt (C) 2009 Doug Coleman.
+! Copyrigt (C) 2009 Doug Coleman, Keith Lazuka
 ! See http://factorcode.org/license.txt for BSD license.
-USING: accessors arrays assocs combinators compression.lzw-gif
+USING: accessors arrays combinators compression.lzw
 constructors destructors grouping images images.loader io
-io.binary io.buffers io.encodings.binary io.encodings.string
-io.encodings.utf8 io.files io.files.info io.ports
-io.streams.limited kernel make math math.bitwise math.functions
-multiline namespaces prettyprint sequences ;
+io.binary io.buffers io.encodings.string io.encodings.utf8
+kernel make math math.bitwise namespaces sequences ;
 IN: images.gif
 
 SINGLETON: gif-image
@@ -37,9 +35,7 @@ ERROR: unknown-extension n ;
 ERROR: gif-unexpected-eof ;
 
 TUPLE: graphics-control-extension
-label block-size raw-data
-packed delay-time color-index
-block-terminator ;
+flags delay-time transparent-color-index ;
 
 TUPLE: image-descriptor
 left top width height flags first-code-size ;
@@ -59,14 +55,16 @@ introducer label comment-data ;
 TUPLE: trailer byte ;
 CONSTRUCTOR: trailer ( byte -- obj ) ;
 
-CONSTANT: image-descriptor HEX: 2c
+CONSTANT: image-descriptor 0x2c
 ! Extensions
-CONSTANT: extension-identifier HEX: 21
-CONSTANT: plain-text-extension HEX: 01
-CONSTANT: graphic-control-extension HEX: f9
-CONSTANT: comment-extension HEX: fe
-CONSTANT: application-extension HEX: ff
-CONSTANT: trailer HEX: 3b
+CONSTANT: extension-identifier 0x21
+CONSTANT: plain-text-extension 0x01
+CONSTANT: graphic-control-extension 0xf9
+CONSTANT: comment-extension 0xfe
+CONSTANT: application-extension 0xff
+CONSTANT: trailer 0x3b
+CONSTANT: graphic-control-extension-block-size 0x04
+CONSTANT: block-terminator 0x00
 
 : <loading-gif> ( -- loading-gif )
     \ loading-gif new
@@ -76,14 +74,6 @@ CONSTANT: trailer HEX: 3b
         V{ } clone >>comment-extensions
         t >>loading? ;
 
-GENERIC: stream-peek1 ( stream -- byte )
-
-M: input-port stream-peek1
-    dup check-disposed dup wait-to-read
-    [ drop f ] [ buffer>> buffer-peek ] if ; inline
-
-: peek1 ( -- byte ) input-stream get stream-peek1 ;
-
 : (read-sub-blocks) ( -- )
     read1 [ read , (read-sub-blocks) ] unless-zero ;
 
@@ -101,9 +91,11 @@ M: input-port stream-peek1
 
 : read-graphic-control-extension ( -- graphic-control-extension )
     \ graphics-control-extension new
-        1 read le> [ >>block-size ] [ read ] bi
-        >>raw-data
-        1 read le> >>block-terminator ;
+        1 read le> graphic-control-extension-block-size assert=
+        1 read le> >>flags
+        2 read le> >>delay-time
+        1 read le> >>transparent-color-index
+        1 read le> block-terminator assert= ;
 
 : read-plain-text-extension ( -- plain-text-extension )
     \ plain-text-extension new
@@ -147,6 +139,9 @@ ERROR: unimplemented message ;
 : interlaced? ( image -- ? ) flags>> 6 bit? ; inline
 : sort? ( image -- ? ) flags>> 5 bit? ; inline
 : color-table-size ( image -- ? ) flags>> 3 bits 1 + 2^ 3 * ; inline
+: transparency? ( image -- ? )
+    graphic-control-extensions>>
+    [ f ] [ first flags>> 0 bit? ] if-empty ; inline
 
 : color-resolution ( image -- ? ) flags>> -4 shift 3 bits ; inline
 
@@ -221,22 +216,30 @@ ERROR: unhandled-data byte ;
     ] with-input-stream ;
 
 : decompress ( loading-gif -- indexes )
-    [ image-descriptor>> first-code-size>> ]
-    [ compressed-bytes>> ] bi
-    lzw-uncompress ;
+    [ compressed-bytes>> ]
+    [ image-descriptor>> first-code-size>> ] bi
+    gif-lzw-uncompress ;
+
+: colorize ( index palette transparent-index/f -- seq )
+    pick = [ 2drop B{ 0 0 0 0 } ] [ nth 255 suffix ] if ;
 
-: apply-palette ( indexes palette -- bitmap )
-    [ nth 255 suffix ] curry V{ } map-as concat ;
+: apply-palette ( indexes palette transparent-index/f -- bitmap )
+    [ colorize ] 2curry V{ } map-as concat ;
 
 : dimensions ( loading-gif -- dim )
     [ image-descriptor>> width>> ] [ image-descriptor>> height>> ] bi 2array ;
 
-: loading-gif>image ( loading-gif -- image )
+: ?transparent-color-index ( loading-gif -- index/f )
+    dup transparency?
+    [ graphic-control-extensions>> first transparent-color-index>> ]
+    [ drop f ] if ;
+
+: gif>image ( loading-gif -- image )
     [ <image> ] dip
     [ dimensions >>dim ]
     [ drop RGBA >>component-order ubyte-components >>component-type ]
     [
-        [ decompress ] [ global-color-table>> ] bi
+        [ decompress ] [ global-color-table>> ] [ ?transparent-color-index ] tri
         apply-palette >>bitmap
     ] tri ;
 
@@ -246,4 +249,4 @@ ERROR: loading-gif-error gif-image ;
     dup loading?>> [ loading-gif-error ] when ;
 
 M: gif-image stream>image ( path gif-image -- image )
-    drop load-gif ensure-loaded loading-gif>image ;
+    drop load-gif ensure-loaded gif>image ;