From 9e7b10b283f44a0fe7caabf1a835ee0116eae5f6 Mon Sep 17 00:00:00 2001
From: Samuel Gomes <samuel_gomes@outlook.com>
Date: Thu, 30 Nov 2023 04:58:41 +0530
Subject: [PATCH] Fix decoder to work correctly with rotating-earth.gif

---
 InForm/extensions/GIFPlay.bas            | 6 ++++--
 examples/DuckShoot/ducks.cfg             | 2 +-
 examples/GIFPlaySample/GIFPlaySample.bas | 4 ++--
 examples/Pelmanism/pelman.dat            | 2 +-
 4 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/InForm/extensions/GIFPlay.bas b/InForm/extensions/GIFPlay.bas
index 0a2177c..0db1fa1 100644
--- a/InForm/extensions/GIFPlay.bas
+++ b/InForm/extensions/GIFPlay.bas
@@ -234,7 +234,7 @@ $IF GIFPLAY_BAS = UNDEFINED THEN
         CLS
 
         ' Blit the rendered frame
-        _PUTIMAGE , renderedFrame
+        _PUTIMAGE , renderedFrame, , , _SMOOTH
 
         DIM idx AS LONG: idx = HashTable_LookupLong(__GIFPlayHashTable(), Id)
 
@@ -419,6 +419,7 @@ $IF GIFPLAY_BAS = UNDEFINED THEN
     END SUB
 
 
+    ' https://commandlinefanatic.com/cgi-bin/showarticle.cgi?article=art011
     FUNCTION __GIF_ReadLZWCode& (sf AS StringFileType, buffer AS STRING, bitPos AS LONG, bitSize AS LONG)
         DIM AS LONG code, p: p = 1
 
@@ -449,6 +450,7 @@ $IF GIFPLAY_BAS = UNDEFINED THEN
     END FUNCTION
 
 
+    ' https://stackoverflow.com/questions/26894809/gif-lzw-decompression
     FUNCTION __GIF_DecodeLZW%% (sf AS StringFileType, bmpMem AS _MEM)
         TYPE __LZWCodeType
             c AS LONG
@@ -520,7 +522,7 @@ $IF GIFPLAY_BAS = UNDEFINED THEN
             END IF
 
             ' Except after clear marker, build new code
-            IF prev <> clearMarker THEN
+            IF prev <> clearMarker AND n < 4096 THEN
                 codes(n).prefix = prev
                 codes(n).length = codes(prev).length + 1
                 codes(n).c = codes(c).c
diff --git a/examples/DuckShoot/ducks.cfg b/examples/DuckShoot/ducks.cfg
index b742e66..bd69e25 100644
--- a/examples/DuckShoot/ducks.cfg
+++ b/examples/DuckShoot/ducks.cfg
@@ -7,4 +7,4 @@
  108 
  39 
  101 
- 2 
+ 1 
diff --git a/examples/GIFPlaySample/GIFPlaySample.bas b/examples/GIFPlaySample/GIFPlaySample.bas
index 643fca9..d515d35 100644
--- a/examples/GIFPlaySample/GIFPlaySample.bas
+++ b/examples/GIFPlaySample/GIFPlaySample.bas
@@ -15,8 +15,8 @@ DIM SHARED PlayBT AS LONG
 
 ': External modules: ---------------------------------------------------------------
 '$INCLUDE:'../../InForm/extensions/GIFPlay.bi'
-'$INCLUDE:'../../InForm/InForm.bi'
 '$INCLUDE:'../../InForm/extensions/MessageBox.bi'
+'$INCLUDE:'../../InForm/InForm.bi'
 '$INCLUDE:'GIFPlaySample.frm'
 
 ': Event procedures: ---------------------------------------------------------------
@@ -103,5 +103,5 @@ END SUB
 
 '$INCLUDE:'../../InForm/InForm.ui'
 '$INCLUDE:'../../InForm/xp.uitheme'
-'$INCLUDE:'../../InForm/extensions/GIFPlay.bas'
 '$INCLUDE:'../../InForm/extensions/MessageBox.bas'
+'$INCLUDE:'../../InForm/extensions/GIFPlay.bas'
diff --git a/examples/Pelmanism/pelman.dat b/examples/Pelmanism/pelman.dat
index 3ffef42..d66c7fd 100644
--- a/examples/Pelmanism/pelman.dat
+++ b/examples/Pelmanism/pelman.dat
@@ -1,3 +1,3 @@
- 0 
+ 12 
  0 
  0