Note that there is an empty space between each Bar/Column Items within the same Series and it is different than the empty space between the Series themselves. The calculation of the size of these two kind of empty spaces is based on the number of the plotted Bar/Column Series and the number of their Items.
It is possible, however, that the number of the pixels distributed for these spaces are not multiple, so that the range of some spaces may include an additional pixel. This behavior may become obvious in scenarios, like yours where the RadHtmlChart is populated with many SeriesItems, so that the mentioned patterns with lighter color may occur. Note that this is not an issue with the control but rather a specific case.
We have an idea to implement SparkLines (similar to the ones in KendoUI
) for the future, which will solve the mentioned issue. However, I cannot provide any time estimates on this implementation, as this functionality has not been requested by our clients yet, and our developers are currently working on tasks with higher priority.
the Telerik team
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