void SetCellWidthPrecision(UINT nCellWidthPrecision);
nCellWidthPrecision
Specifies the width in pixels.
Since we use covered cells as the backbone to the hierarchical grid (wrapped and MRT grid), each visible cell is actually a covering of N number of basic grid cells. Hence the width of a visible cell can only be a whole multiple of the basic grid cell's width, which is set to 4 pixels by default. You can decrease the width of this basic cell using the API below for better precision.
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