GetBitmapClipSegments method (ILEADRaster)

Syntax	short GetBitmapClipSegments(float y, ILEADRasterVariant * pltVarSeg)
Overview	Refer to Creating and Using a Bitmap Region.

Remarks

Gets the segments contained in the region for a particular row.

Call this method only for those rows that are within the region. That is, only those rows from RgnTop to RgnTop + RgnHeight. For the rows not contained in the region, their clip segments will include the whole row.

The segments are returned as an array of pairs of horizontal offsets. The first point in the pair is the beginning of the segment (it is contained in the region). The last point in the pair is the end of the segment. To follow the Windows rules, the end of the segment is the first point NOT CONTAINED in the region.

In most regions, there will be one segment per row. However, some regions can have 0, 1, 2 or more segments.

For example, assume that for a particular row there are two segments. The VARIANT will be filled with 4 values. Let’s call them x0, x1, x2, x3. In this case:

$image\sqrblit.gif$ portion from 0 to x0 – 1 is OUTSIDE the region

$image\sqrblit.gif$ portion from x0 to x1 - 1 is INSIDE the region

$image\sqrblit.gif$ portion from x1 to x2 – 1 is OUTSIDE the region

$image\sqrblit.gif$ portion from x2 to x3 – 1 is INSIDE the region

$image\sqrblit.gif$ portion from x3 to bitmap width – 1 is OUTSIDE the region

The position is unscaled relative to the LEAD bitmap in memory.

The unit of measure is determined by the ScaleMode property.

Elements:	RgnTop property, RgnHeight property
Topics:	Raster Images: Creating and Using a Region