Created Special texture file types (markdown)

Special-texture-file-types.md

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+Besides the default format (a grid of xcount by ycount textures), a number of other special texture file formats are supported by Dynmap.  The currently defined types include the following:
+
+* *GRID* - this is the default format, corresponding to an array of square textures \<xcount\> wide and \<ycount\> high.  Each texture needs to be an even power of 2 pixels across.  The index of the textures is ordered from the top left (index=0) moving to the right across the first row (ending with index=\<xcount\>-1), before advancing to the left edge of the next row (index=\<xcount\>), and so forth.
+
+* *CHEST* - this is the format corresponding to the texture layout for small chests.  The index values are:
+     + 0 : Chest top
+     + 1 : Chest left side
+     + 2 : Chest right side
+     + 3 : Chest front side
+     + 4 : Chest back side
+     + 5 : Chest bottom
+
+* *BIGCHEST* - this is the format corresponding to the texture layout for large chests.  The index values are:
+     + 0 : Chest top - left side
+     + 1 : Chest top - right side
+     + 2 : Chest front - left side
+     + 3 : Chest front - right side
+     + 4 : Chest left side
+     + 5 : Chest right side
+     + 6 : Chest back - left side
+     + 7 : Chest back - right side
+     + 8 : Chest bottom - left side
+     + 9 : Chest bottom - right side
+
+* *SIGN* - this is the format corresponding to the texture layout for signposts.  The index values are:
+     + 0 : Sign front side
+     + 1 : Sign back side
+     + 2 : Sign top
+     + 3 : Sign bottom 
+     + 4 : Sign left side
+     + 5 : Sign right side
+     + 6 : Post front side
+     + 7 : Post back side
+     + 8 : Post left side
+     + 9 : Post right side
+
+* *SKIN* - this is the format corresponding to the texture for a player (or other human shaped skin).  The index values are:
+     + 0 : Face front side
+     + 1 : Face left side
+     + 2 : Face right side
+     + 3 : Face back side
+     + 4 : Face top
+     + 5 : Face bottom
+
+* *CUSTOM* - this is the more flexible format, allowing extraction of arbitrary rectangular textures as indexed textures.  The \<xcount\> and \<ycount\> values are used to detect the scale of the texture image (working on the assumption that the nominal size of the texture is 16 * \<xcount\> by 16 * \<ycount\> pixels).  The attributes of the 'texturefile:' definition need to include one 'tile\<N\>=" attribute for each texture index (where N = 0, 1, 2, etc).  The value of the field corresponds to:
+
+     tile<N>=<source-offset-X>:<source-offset-Y>/<dimension-X>:<dimension-Y>
+
+or, optionally:
+
+     tile<N>=<source-offset-X>:<source-offset-Y>/<dimension-X>:<dimension-Y>/<dest-offset-X>:<dest-offset-Y>
+
+Where:
+* \<source-offset-X\> is the X coordinate of the top left corner of the texture within the texture file, in scaled pixels
+* \<source-offset-Y\> is the Y coordinate of the top left corner of the texture within the texture file, in scaled pixels
+* \<dimension-X\> is the horizontal texture within the texture file, in scaled pixels
+* \<dimension-Y\> is the vertical texture within the texture file, in scaled pixels
+* \<dest-offset-X\> is the X coordinate of the top left corner of the texture in the destination texture (default is 0), in scaled pixels
+* \<dest-offset-Y\> is the Y coordinate of the top left corner of the texture in the destination texture (default is 0), in scaled pixels