X cut doesn't match what's on screen

[kmun]

Describe the bug
Performing an X-Cut in a raster appears to go to the next trace instead of the current one.

To Reproduce

Steps to reproduce the behavior:

1. Create a raster plot with 3 distinct traces. By default the Y axis should be numbered 0, .5, 1, 1.5, 2, 2.5, 3.
2. Verify the first trace is a rectangle starting at 0 and ending at 1 on the Y axis, and the second is from 1 to 2 and third from 2 to 3.
3. Move your mouse to below the 0.5 on the Y axis and press X to perform an X cut
4. Verify the X-Cut matches the first trace
5. Press X again to exit the X-Cut
6. Move your mouse to above the 0.5 on the Y axis and press X to perform an X cut
7. Verify the X-Cut now matches the second trace, even though the mouse was physically on the 1st trace.

Expected behavior
I would think the X-Cut should match the trace under the cursor when you press the X key, it appears to round up so at 0.5 Y index it prints trace 1 and at 1.5 Y index it prints trace 2.

jsFiddle

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Screenshots
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Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
Add any other context about the problem here.

[maihde]

@kmun the xCut (and yCut/pCut) logic has always been hardcoded to assume one raster layer.

sigplot/js/sigplot.js

Line 3546 in 480cec3

Gx.x_cut_data = Gx.lyr[0].buf.slice(start, finish);

.

Do you have a specific use-case for this or was it just something you found while playing around?

I think the correct behavior is that each raster layer turns into it's own line (with a different color per raster layer). That way if you had overlapping rasters you could make cuts and see each layer.

[kmun]

sorry, I should have explained better. In my case I don't have a lot of raster "lines"; as an example, in a plot there may only be 6 raster lines so each line is about 1 inch wide on my screen. If I'm at the top of the 1 inch wide line it shows the x cut properly, if I'm anywhere after 50% into the 1 inch line it shows the x cut for the NEXT raster line. I do use this a lot. Most of my plots contain less than 20 lines and since the window is about 10 inches tall on my display, that's a 1/2 inch wide line. Most of my users will put the curser in vertical and horizontal center of the line which means they will often be viewing the next line when doing an X cut. I've included a REALLY BAD powerpoint diagram trying to show the issue. I can't upload a real plot for security reasons. Sorry. BTW, thanks for the follow up.

[maihde]

@kmun thanks for the picture and description. I have identified the source of the issue and will fix it soon.

…

On Tue, May 18, 2021 at 8:08 AM kmun ***@***.***> wrote: sorry, I should have explained better. In my case I don't have a lot of raster "lines"; as an example, in a plot there may only be 6 raster lines so each line is about 1 inch wide on my screen. If I'm at the top of the 1 inch wide line it shows the x cut properly, if I'm anywhere after 50% into the 1 inch line it shows the x cut for the NEXT raster line. I do use this a lot. Most of my plots contain less than 20 lines and since the window is about 10 inches tall on my display, that's a 1/2 inch wide line. Most of my users will put the curser in vertical and horizontal center of the line which means they will often be viewing the next line when doing an X cut. I've included a REALLY BAD powerpoint diagram trying to show the issue. I can't upload a real plot for security reasons. Sorry. BTW, thanks for the follow up. [image: Example of X-Cut issue] <https://user-images.githubusercontent.com/45660362/118647876-d7a4e580-b7af-11eb-9945-d76e1b422158.jpg> — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#103 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AABYEIRWANL3YNP3T4NHHSTTOJKCTANCNFSM44C4RLDA> .

[maihde]

@kmun I don't know what version of SigPlot you are running, but I have fixed the issue here:

spectriclabs@01b06a0

If you are able to run the master branch from spectriclabs/sigplot then it will include the fix.

The good news is, the fix is very easy, so you should be able to port it into whatever version you are running by altering these lines:

sigplot/js/sigplot.js

Line 3540 in 480cec3

var row = Math.round((ypos - Gx.lyr[0].ystart) / Gx.lyr[0].ydelta);

sigplot/js/sigplot.js

Line 3684 in 480cec3

var col = Math.round((xpos - Gx.lyr[0].xstart) / Gx.lyr[0].xdelta);