Feature/jsonformat

json format.txt

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+
+#JSON format#
+
+object {	
+version:	int	//this doc describes version 1
+timescale:	int	
+hasAlpha:	boolean	
+framesize:	object { //frame size (currently ignored by player)
+	width:	int	
+	height:	int	
+	}	
+frames:	array [	
+	object {	//one object per frame.. pass object to blit callback
+		x:	string	//frame blit description base64 encoded into string (defined below)
+		d:	number	//frame display duration (in timescale defined above)
+		m:  //optional user entered metadata will be returned in callback - any format
+	}	
+	//additonal frames
+	]	
+}
+
+
+#Frame Blit Description#
+
+The blit description is 1 or more blits packets, each prefaced by a PPS description. The PPS describes the attributes of the blit packets following it.
+Format below is var name, followed by size _in bits_. Sizes in {} are based on values encoded previously in the stream.
+
+##PPS##
+blit_type	8 //describes the type of blit packet encoded (see list below)
+src_image_index	8 //the source atlas image to blit from, if a frame is made of multiple src atlas images, multiple PPS must be encoded.
+block_size	5	//pixel size of blits (width and height)
+frame_type	3	//{0 = iFrame, 1 = pFrame }
+blitcount	16	//number of blits in this pps, next PPS will start at next byte start after the last blit in this pps
+
+//all the follwing bitdepth values encode the bitdepth of values encoded in the blit packets follwing this PPS
+srcxy_bitdepth	4	//sx/y bitdepth (only need one, since we make sure src image is square
+dest_x_bitdepth	4
+dest_y_bitdepth	4	
+src_w_bitdepth	4	
+src_h_bitdepth	4	
+dest_w_bitdepth	4	
+dest_h_bitdepth	4	
+reserved	52	//reserved
+
+
+##Blit Packets##	
+(if bitdepth for a value is defined as zero in the PPS, use 0 as retrieved value for further computation)
+
+###Blit Type 1###
+(currently blit type 1 is the only defined type)
+Blit Type 1 copies a single block of size src_block_width x src_block_height, from the atlas image at index src_image_index at x,y offset of src_x, src_y into the canvas at offset dest_x, dest_y (scaling it to size of dest_block_width, dest_block_height if defined).
+
+src_x	{srcxy_bitdepth}	//to retrieve nominal x multiply by block_size
+src_y	{srcxy_bitdepth}	//to retrieve nominal y multiply by block_size
+src_block_width	{src_w_bitdepth}	//computed as (1+value) in blocksize, to retrieve nominal pixel width multiply by block_size
+src_block_height	{src_h_bitdepth}	//computed as (1+value) in blocksize, to retrieve nominal pixel height multiply by block_size
+dest_x	{dest_x_bitdepth}	//to retrieve nominal x multiply by block_size
+dest_y	{dest_y_bitdepth}	//to retrieve nominal y multiply by block_size
+dest_block_width	{dest_w_bitdepth}	//computed as (1+value) in blocksize, to retrieve nominal pixel width multiply by block_size (if zero, then src size)
+dest_block_height	{dest_h_bitdepth}	//computed as (1+value) in blocksize, to retrieve nominal pixel height multiply by block_size (if zero, then src size)