IntensityGrid and logarithmic Scaling

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ahe
Posts: 51
Joined: Tue Aug 11, 2015 4:33 pm
Location: Düsseldorf, DE

IntensityGrid and logarithmic Scaling

Post by ahe » Tue Aug 02, 2016 1:31 pm

There seems to be a new issue with logarithmic scaling with IntensityGridSeries, in our application it looks like the geometry of the grid gets distorted:
application_logarithmic.png
application_logarithmic.png (10.34 KiB) Viewed 14672 times
I created a minimal test application to reproduce it. While it is not as bad, I can still make out a few odd edges where there should be none.

Expected behaviour (LighningCharts 6.5.8):
intensitygrid_logarithmic_v6_5_8.png
intensitygrid_logarithmic_v6_5_8.png (138.91 KiB) Viewed 14672 times
LighningCharts 7.1.1 (7.0.18 identical):
intensitygrid_logarithmic_v7_1_1.png
intensitygrid_logarithmic_v7_1_1.png (26.74 KiB) Viewed 14672 times

Windows 7 pro 64bit SP1, Intel i7, 16GB RAM, GeForce GT 730, current drivers, two HD-monitors.

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ArctionPasi
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Location: Finland

Re: IntensityGrid and logarithmic Scaling

Post by ArctionPasi » Tue Aug 02, 2016 2:05 pm

Hi!

could you send that app to our support by e-mail so we can take a deeper look?
LightningChart Support Team, PT

ahe
Posts: 51
Joined: Tue Aug 11, 2015 4:33 pm
Location: Düsseldorf, DE

Re: IntensityGrid and logarithmic Scaling

Post by ahe » Tue Aug 02, 2016 2:08 pm

[continued]

Sample code, tested with 6.5.8, 7.0.18 and 7.1.1 (change the references and use respective #define in Form1.cs)

It gets stranger: v7 does only render with PixelRendering=false and ScaleType.Linear. I can't figure out why it's working with v6 and in the v7.1-SDK's demo app though.
Attachments
AL_IntensityGrid_Logarithmic.zip
Sample code
(11.3 KiB) Downloaded 584 times

ahe
Posts: 51
Joined: Tue Aug 11, 2015 4:33 pm
Location: Düsseldorf, DE

Re: IntensityGrid and logarithmic Scaling

Post by ahe » Tue Aug 02, 2016 2:26 pm

OK, I found out the problem:

I am using IntensityGridSeries.SetValuesData with data[][]. This only seems to be compatible with PixelRendering and not with Interpolation.

When I changed it to IntensityGridSeries.Data with IntensityPoint[,], it works as expected:
intensitygrid_logarithmic_v7_1_1_data.png
intensitygrid_logarithmic_v7_1_1_data.png (110.05 KiB) Viewed 14667 times

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ArctionPasi
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Re: IntensityGrid and logarithmic Scaling

Post by ArctionPasi » Tue Aug 02, 2016 2:55 pm

That's right, SetValuesData is suitable only for PixelRendering. PixelRendering is suitable for linear axes only, because it uses GPU side texture, and that is naturally evenly spaced in screen space. I'm glad you were able to solve this :D
LightningChart Support Team, PT

ahe
Posts: 51
Joined: Tue Aug 11, 2015 4:33 pm
Location: Düsseldorf, DE

Re: IntensityGrid and logarithmic Scaling

Post by ahe » Fri Aug 05, 2016 1:47 pm

Reproduced_7_0_18.png
Reproduced_7_0_18.png (93.54 KiB) Viewed 14645 times
Occurs in 7.0.18, but not in 7.1.1 or 6.5.8. Sample source is attached.

I'll try updating to 7.1.1 hoping that it won't break anything.
Attachments
AL_IntensityGrid_Logarithmic.zip
Source code
(11.33 KiB) Downloaded 605 times

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ArctionPasi
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Location: Finland

Re: IntensityGrid and logarithmic Scaling

Post by ArctionPasi » Fri Aug 05, 2016 2:21 pm

I sent you link to intermediate build 7.1.1.2 by e-mail. With that it looks like:
Fixed intensity chart
Fixed intensity chart
heatmap.jpg (116.21 KiB) Viewed 14642 times
LightningChart Support Team, PT