[egui_plot] linked axes wrong scale/bounds

[jordens]

Describe the bug

Linked axes are inaccurately linked. Compare the y axis of the top left and right plots in the screenshot.

There are a couple more fragility issues with axes linking but this appears to be a dominant one.

To Reproduce Steps to reproduce the behavior:

1. https://www.egui.rs/#Demo
2. Select "Plot" from Egui demos
3. Select "Linked Axes" tab
4. Observe incorrect y axis scaling between top left and right plots (range in top left plot is larger)

Expected behavior Correctly scaled and linked axis.

Screenshots

Desktop (please complete the following information):

• OS: Ubuntu
• Browser chrome
• Version 118.0.5993.70

Additional context egui 0.23 egui_plot 0.23 (also still occurs in current master as of fd75adb)

[bircni]

Seems like it's not happening in egui 0.28 anymore

@jordens

[jordens]

It is:

[bircni]

@YgorSouza what do you think?

[YgorSouza]

It's still the same as when the issue was opened. I don't think anyone has worked on that. I noticed that this change makes the axes match perfectly:

M demo/src/plot_demo.rs
@@ -652,7 +652,7 @@ impl LinkedAxesDemo {
                 .link_cursor(link_group_id, self.link_cursor_x, self.link_cursor_y)
                 .show(ui, Self::configure_plot);
             Plot::new("right-top")
-                .data_aspect(2.0)
+                .data_aspect(1.9)
                 .width(150.0)
                 .height(250.0)
                 .y_axis_label("y")

But I don't know why. Clearly the linked axes don't deal with aspect ratio differences well, but even if we make both plots the same height and width, we have to set the aspect ratio on the second one to 1.05 instead of 1.0 for them to match. Not sure where that is coming from. Removing the data_aspect from both plots also works, so that's probably the place to look.