Feature request (bug?) center handle position in HeatmapChart Pixels

[wolfig]

Use Case
I want to use the HeatmapChart to visualize the progress and result of a 2D scanning process. This means, my program sends X * Y equidistant setting values to two instruments and registers one readout value z to each of the x, y settings.

Current Situation
When rendering the corresponding data, the handle/origin of each of the pixels representing one x,y,z triple is not centered.

Example: consider a data set with 4 x,y,z "pixels"
x = [ 10.4, 13.5 ]
y = [ -3.2, -3.05 ]
z = [ 1, 2, 3, 4 ]

The resulting chart looks like this:

Problem / Bug
For a user, the positions of the scan values is confusing. I hope the image tells enough what I mean.

Expected Behavior / Feature Request
Adjust the alignment of axes and pixels in a way that the x, y coordinates are centered in the "pixels" representing the x, y, z data. This behavior can be optional where the default is the existing behavior.
Here an illustration of the expected behavior:

Note
The expected behavior requires the suppression of minor ticks and the explicit setting of ticks which is (to my knowledge) not possible with the current implementation of DefaultAxis. I will create another issue asking for this feature.

Environment:

• Java-Version: FAIR CS environment
• ChartFx version: 11.2.7

[RalphSteinhagen]

@wolfig the present implementation is derived from 2D histograms that are defined via their bin boundaries and not their centres. You could either change the definition of the underlying DataSet w.r.t. how the data is being represented or make a "hack" involving the axis ranges.