Data type for custom MaxiCode finder drawing callback-function.
This callback function can be set with BCGetFuncDrawRing(). When set the MaxiCode finder drawing functions do not generate any output. Instead they call the active callback function.
When Windows-GDI drawing is started (with BCDraw()) then drawDC contains the Windows device contexts (if set). The variables x, and y specify the position of center of the ring. If drawDC and targetDC are not set then these variables are given in millimeters, where the origin of the coordinate system is the upper, left coordinate of the barcode. The positive X-axis points to the right and the positive Y-axis points downwards.
If drawDC or targetDC are set then the parameters x and y use the current logical coordinate system and the logical units of these device contexts.
- Note:
- The user-defined data (customData) is shared by all callback functions.
- Parameters:
-
| [in,out] | customData | User-defined data. |
| [in,out] | drawDC | The device context. |
| [in] | x | The x-coordinate (=horizontal) of the ring center. |
| [in] | y | The y-coordinate (=vertical) of the ring center. |
| [in] | rInner | The radius of the inner margin of the ring. |
| [in] | rOuter | The radius of the outer margin of the ring. |
- Return values:
-
| ErrOk | Everything went fine, and the drawing continues. |
| !=ErrOk | Something went wrong, the drawing function returns with the returned error value. |
- See also:
- BCGetFuncDrawRing(), BCSetFuncDrawRing(), BCDrawCB()
