Automatic tooltips with values

[ArnaudJamin]

Hello,

I'm wondering if ImPlot is able to draw tooltip with values of where the mouse is. Something like this:

This was done the same way as the "Custom Plotters and Tooltips" demo which require to search through the data. I was wondering if ImPlot might have a faster way to do this, since it already iterate over the data to draw the graph.

Thanks for this great library!

[Davido71]

Yes there is a way, It's quite easy to do. The version I use is older (v0.12) but I'm pretty sure it works the same way in newer versions.

if(ImPlot::BeginPlot(...)) { // Plot stuff if (ImPlot::IsPlotHovered() && GImGui->HoveredIdTimer > 0.2) { ImPlotPoint mouse = ImPlot::GetPlotMousePos(); // Mouse offsets within the chart const int32_t i = static_cast<int32_t>(mouse.x); // x can be used as an index into your datasets ImGui::BeginTooltip();

    ImGui::Text("Label 1:  $%.2f", dataSet1[i]);
    ImGui::Text("Label 2:  $%.2f", dataSet2[i]);

    ImGui::EndTooltip();
}
ImPlot::EndPlot();

}

David

On Tue, Sep 19, 2023 at 2:01 PM ArnaudJamin @.***> wrote:

Hello,

I'm wondering if ImPlot is able to draw tooltip with values of where the mouse is. Something like this: [image: image] https://user-images.githubusercontent.com/87346845/269080018-f0f00639-81c3-421b-995a-e43714b18681.png

This was done the same way as the "Custom Plotters and Tooltips" demo which require to search through the data. I was wondering if ImPlot might have a faster way to do this, since it already iterate over the data to draw the graph.

Thanks for this great library!

— Reply to this email directly, view it on GitHub https://github.com/epezent/implot/issues/514, or unsubscribe https://github.com/notifications/unsubscribe-auth/AOS57YUGUW6E7TADVOTVJ7LX3H22LANCNFSM6AAAAAA462QQ7A . You are receiving this because you are subscribed to this thread.Message ID: @.***>

[ArnaudJamin]

I don't think this solution always works. I'm using a circular buffer of ImVec2 where x is the time and y is the value. ImPlot::GetPlotMousePos().x returns the time, so a search in the array would be required.

[Davido71]

I use "circular" buffers as well to capture real-time stock data. I found that using x axis as time wasn't very feasible in my case. It was better to use the x axis as a reference to the data. I used std::deque as the datatype. When adding a new element to the list, call .push_front() and when there are enough elements, start calling .pop_back() to limit my data size. This way there is a sliding window from left to right of data that you can easily reference in your tooltip.

Quick example how I reference tons of data within my charts.

using dataset_t = std::deque; using timestamp_t = std::deque<int64_t>; using volume_t = std::deque<int32_t>;

struct candles_t { dataset_t open; dataset_t close; dataset_t high; dataset_t low; volume_t volume; timestamp_t timestamp; }

I create functions that implot can use where I can extract whatever data I want. In this case I want the close. ImPlotPoint candleClose(void* data, int i) { candles_t* c = reinterpret_cast<candles_t*>(data); return ImPlotPoint(i, c->close[i]); }

To plot a I call ImPlot::PlotLineG("Candles", candleClose, &candles, size);

Example of my tooltip [image: image.png]

I hope this helps, David

On Wed, Sep 20, 2023 at 2:21 PM ArnaudJamin @.***> wrote:

I don't think this solution always works. I'm using a circular buffer of ImVec2 where x is the time and y is the value. ImPlot::GetPlotMousePos().x returns the time, so a search in the array would be required.

— Reply to this email directly, view it on GitHub https://github.com/epezent/implot/issues/514#issuecomment-1728372971, or unsubscribe https://github.com/notifications/unsubscribe-auth/AOS57YU2SOJZMNEPFX6LB3DX3NF3VANCNFSM6AAAAAA462QQ7A . You are receiving this because you commented.Message ID: @.***>

[ozlb]

check implot_demo tooltip example

[ArnaudJamin]

I was wondering if implot had a built in functionality to do tooltips without having to search inside the data (which is what the tooltip demo does). Or have a way to get the value at specific "time" without searching.

Thanks!