====== Heightfield:CombineMaps filter ======



===== Filter info =====

^  Description | The ''CombineMaps'' filter may be used to combine two heightfields using a variety of operations, such as add, subtract, replace, min, max, etc. |
^  Author | [[user>Aaron]] |
^  Plugin | [[bundywiki>plugins:calc:ZG_combiner|ZG_combiner]] ^

===== Looks like =====

| {{:plugins:calc:zeograph:filters:hf_combinemaps.png}} |


===== Input pins =====

^  Name  ^  Type  ^  Default value  ^ Description ^
|  //hMap//  |  hvar  |  N/A  | A handle to a map. |
|  //hMap2//  |  hvar  |  N/A  | A handle to a second map, which is to be combined with the first. |
|  //xOffset//  |  int  |  0  | The alignment offset, in pixels, in the x direction (east/west) of the second map relative to the first. The interpretation of this value depends on the 'x-axis origin' option (see below). |
|  //yOffset//  |  int  |  0  | The alignment offset, in pixels, in the y direction (north/south) of the second map relative to the first. The interpretation of this value depends on the  'y-axis origin' option (see below). |

===== Output pins =====

^ Name ^ Type ^ Description ^
|  //hMap//  |  hvar  | A handle to the map (handle is passed through from input to output). |

===== Options =====

The [[plugins:calc:zeograph:userguide:filters:options|filter options]] window for the ''CombineMaps'' filter looks like:

| {{:plugins:calc:zeograph:filters:hf_combinemaps_options.png}} |

The options are as follows:



==== Operation =====

The //Operation// field determines how the two heightfield maps are to be combined. Supported operations include:

^ Operation ^ Description ^
| Add | Output height = //hMap1// height + //hMap2// height |
| Subtract | Output height = //hMap1// height - //hMap2// height |
| Min | Output height = minimum(//hMap1// height, //hMap2// height) |
| Min | Output height = maximum(//hMap1// height, //hMap2// height) |
| Replace | Output height = //hMap2// height |
| Multiply | Output height = //hMap1// height * //hMap2// height |



==== X-axis origin =====

The x-axis origin option may be either //left//, //centre// or //right//. This determines how the //xOffset// input pin value is used to align the second map with the first in the horizontal axis. 

^  Left  | The left edge of //hMap2// will be aligned //x// pixels to the right of the left edge of //hMap1//. |
^  Center  | The centre of //hMap2// (along the horizontal axis) will be aligned //x// pixels to the right of the centre of //hMap1//. | 
^  Right  | The right edge of //hMap2// will be aligned //x// pixels to the left of the right edge of //hMap1//. |

... where in all cases, //x// is the the value of the //xOffset// input pin.


==== Y-axis origin =====

The x-axis origin option may be either //bottom//, //centre// or //top//. This determines how the //yOffset// input pin value is used to align the second map with the first in the vertical axis. 

^  Bottom  | The bottom edge of //hMap2// will be aligned //y// pixels above the bottom edge of //hMap1//. |
^  Centre  | The centre of //hMap2// (along the vertical axis) will be aligned //y// pixels above the centre of //hMap1//. | 
^  Top  | The top edge of //hMap2// will be aligned //y// pixels below of the top edge of //hMap1//. |

... where in all cases, //y// is the the value of the //yOffset// input pin.

===== Comments =====

None.