This reference page is linked to from the following overview topics: Hit Regions.
Detailed Description
Describes the properties of a region used for built-in hit testing of items in the interactive renderer.
#include <gfx.h>
Public Member Functions |
|
| HitRegion () | |
Public Attributes |
|
| int | type |
| The region type. |
|
| int | dir |
| Region direction. |
|
| int | crossing |
| If nonzero, elements that are contained
within or that cross the region boundary are hit. |
|
| int | epsilon |
| Specifies the distance in pixels outside the
pick point within which elements may be and still be hit. |
|
| union { | |
| POINT pt | |
| RECT rect | |
| CIRCLE circle | |
| POINT * pts | |
| }; | |
Constructor & Destructor Documentation
| HitRegion | ( | ) | [inline] |
{ dir = RGN_DIR_UNDEF; size = sizeof(HitRegion);}
Member Data Documentation
| int type |
The region type.
One of the following values
- POINT_RGN A single point.
- RECT_RGN A rectangular region.
- CIRCLE_RGN A circular region.
- FENCE_RGN An arbitrary multi-point polygon region.
| int dir |
| int crossing |
If nonzero, elements that are contained within or that cross the region boundary are hit.
If zero, only those elements entirely within the boundary are hit. This is not used for point hit testing.
| int epsilon |
Specifies the distance in pixels outside the pick point within which elements may be and still be hit.
This is not used for rect or circle testing, is sometimes used with fence hit testing, where it doubles the size of the region, especially when selecting subobject edges or vertices and is always used for point hit testing.
| POINT pt |
| POINT* pts |
| union { ... } |
