GifLoader done. SDL_Image dependency removed from Windows version. TBD on OSX and Linux

gif.c

@@ -13,6 +13,7 @@
 #define PLAINTEXT_EXTENSION    0x01
 
 #define READ(dst, size) memcpy(dst, buffer, size); buffer += size
+
 typedef struct
 {
     unsigned short width;
@@ -277,7 +278,7 @@ static int read_sub_blocks( unsigned char* buffer, unsigned char **data )
         }
 
         data_length += block_size;
-        *data = realloc( *data, data_length );
+        *data = (unsigned char*)realloc( *data, data_length );
 
         // TODO this could be split across block size boundaries
 		READ(*data + index, block_size);
@@ -288,7 +289,7 @@ static int read_sub_blocks( unsigned char* buffer, unsigned char **data )
     return data_length;
 }
 
-static int process_image_descriptor( unsigned char* buffer,
+unsigned char* process_image_descriptor( unsigned char* buffer,
                                     rgb *gct,
                                     int gct_size,
                                     int resolution_bits )
@@ -299,7 +300,7 @@ static int process_image_descriptor( unsigned char* buffer,
     unsigned char *compressed_data = NULL;
     unsigned char lzw_code_size;
     int uncompressed_data_length = 0;
-    //unsigned char *uncompressed_data = NULL;
+    unsigned char *uncompressed_data = NULL;
 
     // TODO there could actually be lots of these
 	READ(&image_descriptor, 9);
@@ -316,19 +317,17 @@ static int process_image_descriptor( unsigned char* buffer,
     height = image_descriptor.image_height;
     uncompressed_data_length = image_descriptor.image_width *
     image_descriptor.image_height;
-    uncompressed_data = malloc( uncompressed_data_length );
+    uncompressed_data = (unsigned char*)malloc( uncompressed_data_length );
 
     uncompress( lzw_code_size, compressed_data, compressed_data_length,
                uncompressed_data );
 
-done:
-    if ( compressed_data )
-        free( compressed_data );
+    if ( compressed_data ) free( compressed_data );
 
     //if ( uncompressed_data )
     //    free( uncompressed_data );
 
-    return disposition;
+    return uncompressed_data;
 }
 
 static int process_extension( unsigned char* buffer )
@@ -378,6 +377,30 @@ static int process_extension( unsigned char* buffer )
  *  GIF-encoded file.  This should point to the first byte in
  *  the file when invoked.
  */
+
+unsigned char* LoadPalette(unsigned char *buffer) {
+	unsigned char header[7];
+	screen_descriptor_t screen_descriptor;
+	int color_resolution_bits;
+
+	int global_color_table_size = 0;  // number of entries in global_color_table
+	rgb *global_color_table = NULL;
+
+	READ(header, 6);
+	READ(&screen_descriptor, 7);
+
+	color_resolution_bits = ((screen_descriptor.fields & 0x70) >> 4) + 1;
+	global_color_table = (rgb *)calloc(1, 768);
+
+	if (screen_descriptor.fields & 0x80) {
+		global_color_table_size = 1 << (((screen_descriptor.fields & 0x07) + 1));
+
+		//global_color_table = (rgb *)malloc(3 * global_color_table_size);
+		READ(global_color_table, 3 * global_color_table_size);
+	}
+	return (unsigned char*)global_color_table;
+}
+
 static unsigned char* process_gif_stream(unsigned char *buffer, unsigned short* w, unsigned short* h)
 {
     unsigned char header[ 7 ];
@@ -400,7 +423,7 @@ static unsigned char* process_gif_stream(unsigned char *buffer, unsigned short*
         fprintf( stderr,
                 "Invalid GIF file (header is '%s', should be 'GIF89a')\n",
                 header );
-        return;
+        return NULL;
     }
 
     // Followed by a logical screen descriptor
@@ -433,18 +456,15 @@ static unsigned char* process_gif_stream(unsigned char *buffer, unsigned short*
         switch ( block_type )
         {
             case IMAGE_DESCRIPTOR:
-                if ( !process_image_descriptor( buffer, 
-                                               global_color_table, 
-                                               global_color_table_size,
-                                               color_resolution_bits ) )
-                {
-                    return;
-                }
+				return process_image_descriptor(buffer,
+					global_color_table,
+					global_color_table_size,
+					color_resolution_bits);
                 break;
             case EXTENSION_INTRODUCER:
                 if ( !process_extension( buffer ) )
                 {
-                    return;
+                    return NULL;
                 }
                 break;
             case TRAILER:
@@ -452,9 +472,10 @@ static unsigned char* process_gif_stream(unsigned char *buffer, unsigned short*
             default:
                 fprintf( stderr, "Bailing on unrecognized block type %.02x\n",
                         block_type );
-                return;
+                return NULL;
         }
     }
+	return NULL;
 }
 
 
@@ -462,7 +483,7 @@ unsigned char* LoadGif(unsigned char *buffer, unsigned short* w, unsigned short*
 	return process_gif_stream(buffer, w, h);
 }
 
-int main( int argc, char *argv[] )
+/*int main( int argc, char *argv[] )
 {
     FILE* gif_file;
     
@@ -483,4 +504,4 @@ int main( int argc, char *argv[] )
     process_gif_stream( gif_file );
     
     fclose( gif_file );
-}
+}*/