square root axis?

[rowlesmr]

Hi

I've just discovered this library and am enjoying it quite a lot! I have a line plot that I'd like to make that requires a square root scale.

Which files/functions do I need to look at in order to add this functionality? I'm assuming I can take inspiration from the log10 scale functions.

Thanks.

[epezent]

Custom scales are now possible with SetupAxisScale (see https://github.com/epezent/implot/discussions/370#discussioncomment-2978803). Note that this is somewhat experimental in the sense that scaling will work correctly, but tick placement may not be optimal for the desired scale. Sometime in the future, we may expose custom tick Locators for this purpose. Let me know how this works for your application and we'll go from there. Thanks!

// Callback signature for axis transform.
typedef double (*ImPlotTransform)(double value, void* user_data);

// Sets an axis' scale using user supplied forward and inverse transfroms.
void SetupAxisScale(ImAxis axis, ImPlotTransform forward, ImPlotTransform inverse, void* data=NULL);

Example:

static inline double TransformForward_Sqrt(double v, void*) {
    return sqrt(v);
}

static inline double TransformInverse_Sqrt(double v, void*) {
    return v*v;
}

...

if (ImPlot::BeginPlot("Sqrt")) {
    ImPlot::SetupAxis(ImAxis_X1, "Linear");
    ImPlot::SetupAxis(ImAxis_Y1, "Sqrt");
    ImPlot::SetupAxisScale(ImAxis_Y1, TransformForward_Sqrt, TransformInverse_Sqrt);
    ImPlot::PlotLine(...);
    ImPlot::EndPlot();
}