From 969ba9bcb55ca0c30244603e2ad424481da8cc08 Mon Sep 17 00:00:00 2001 From: Julius Schmitt Date: Thu, 22 Jan 2026 20:44:40 +0100 Subject: [PATCH] logarithmic scaling added; missing the step fn for now --- examples/example_knob.rs | 3 +- src/config.rs | 4 ++- src/render.rs | 11 +++---- src/widget.rs | 62 +++++++++++++++++++++++++--------------- 4 files changed, 50 insertions(+), 30 deletions(-) diff --git a/examples/example_knob.rs b/examples/example_knob.rs index 439f108..b0271c2 100644 --- a/examples/example_knob.rs +++ b/examples/example_knob.rs @@ -82,7 +82,7 @@ impl eframe::App for KnobDemo { .enumerate() { ui.vertical(|ui| { - let mut knob = Knob::new(&mut self.values[i], 0.0, 1.0, *config) + let mut knob = Knob::new(&mut self.values[i], 0., 3., *config) .with_label(*label, LabelPosition::Bottom) .with_background_arc(self.show_bg_arc) .with_show_filled_segments(self.show_filled) @@ -90,6 +90,7 @@ impl eframe::App for KnobDemo { .with_step(self.use_step.then_some(0.02)) .with_double_click_reset(0.5) .with_middle_scroll(); + //.with_logarithmic_scaling(); if *label == "Wiper, Sweep" { knob = knob.with_sweep_range(0.25, 0.75).with_size(50.0); diff --git a/src/config.rs b/src/config.rs index 05b93e4..d78e1c8 100644 --- a/src/config.rs +++ b/src/config.rs @@ -18,6 +18,7 @@ pub struct KnobConfig { pub(crate) max_angle: f32, pub(crate) reset_value: Option, pub(crate) allow_scroll: bool, + pub(crate) logarithmic_scaling: bool, } impl KnobConfig { @@ -39,7 +40,8 @@ impl KnobConfig { show_background_arc: true, show_filled_segments: true, reset_value: None, - allow_scroll:false + allow_scroll:false, + logarithmic_scaling: false, } } } diff --git a/src/render.rs b/src/render.rs index 3a15aba..2bde084 100644 --- a/src/render.rs +++ b/src/render.rs @@ -6,27 +6,28 @@ use crate::style::{KnobStyle, LabelPosition}; pub(crate) struct KnobRenderer<'a> { config: &'a KnobConfig, value: f32, + raw: f32, min: f32, max: f32, } impl<'a> KnobRenderer<'a> { - pub fn new(config: &'a KnobConfig, value: f32, min: f32, max: f32) -> Self { + pub fn new(config: &'a KnobConfig, value: f32, raw: f32, min: f32, max: f32) -> Self { Self { config, value, + raw, min, max, } } pub fn compute_angle(&self) -> f32 { - if self.min == self.max || self.value.is_nan() { + if self.min == self.max || self.raw.is_nan() { self.config.min_angle } else { self.config.min_angle - + (self.value - self.min) / (self.max - self.min) - * (self.config.max_angle - self.config.min_angle) + + self.raw * (self.config.max_angle - self.config.min_angle) } } @@ -99,7 +100,7 @@ impl<'a> KnobRenderer<'a> { if self.config.show_filled_segments { let filled_segments = (segments as f32 - * ((self.value - self.min) / (self.max - self.min)).clamp(0.0, 1.0)) + * self.raw.clamp(0.0, 1.0)) as usize; if filled_segments > 0 { diff --git a/src/widget.rs b/src/widget.rs index 575895d..c224670 100644 --- a/src/widget.rs +++ b/src/widget.rs @@ -1,4 +1,4 @@ -use egui::{Color32, Response, Sense, Ui, Widget}; +use egui::{remap, Color32, Response, Sense, Ui, Widget}; use crate::config::KnobConfig; use crate::render::KnobRenderer; @@ -168,16 +168,25 @@ impl<'a> Knob<'a> { self.config.allow_scroll = true; self } + pub fn with_logarithmic_scaling(mut self) -> Self { + self.config.logarithmic_scaling = true; + self + } } impl Widget for Knob<'_> { - fn ui(self, ui: &mut Ui) -> Response { + fn ui(mut self, ui: &mut Ui) -> Response { if self.value.is_nan() { *self.value = self.min; } - let current_value = *self.value; - let renderer = KnobRenderer::new(&self.config, current_value, self.min, self.max); + let mut raw = if self.config.logarithmic_scaling { + remap(*self.value, self.min..=self.max, 1.0..=10.0).log(10.0) + } else { + remap(*self.value, self.min..=self.max, 0.0..=1.0) + }; + + let renderer = KnobRenderer::new(&self.config, *self.value, raw, self.min, self.max); let adjusted_size = renderer.calculate_size(ui); let (rect, response) = ui.allocate_exact_size(adjusted_size, Sense::click_and_drag()); @@ -185,36 +194,44 @@ impl Widget for Knob<'_> { let mut response = response; if response.dragged() { let delta = response.drag_delta().y; - let range = self.max - self.min; + let range = 1.0; let step = self.config.step.unwrap_or(range * self.config.drag_sensitivity); - let new_value = (*self.value - delta * step).clamp(self.min, self.max); + raw = (raw - delta * step).clamp(0.0,1.0); - *self.value = if let Some(step) = self.config.step { - let steps = ((new_value - self.min) / step).round(); - (self.min + steps * step).clamp(self.min, self.max) + /*raw = if let Some(step) = self.config.step { + let steps = ((raw - 1.0) / step).round(); + (steps * step).clamp(1.0, 2.0) } else { - new_value - }; + raw + };*/ - if self.value.is_nan() { - *self.value = self.min; - } + /*if self.value.is_nan() { + *self.value = 0.0; + }*/ response.mark_changed(); - } else if response.double_clicked() { - if let Some(reset_value) = self.config.reset_value { - *self.value = reset_value - } - } else if response.hovered() & self.config.allow_scroll { + } else if response.hovered() & self.config.allow_scroll { if let Some(scoll) = ui.input(|input| { input.events.iter().find_map(|e| match e { egui::Event::MouseWheel { delta, .. } => Some(*delta), _ => None, }) }) { - *self.value = (*self.value + raw = (raw + scoll.y * self.config.step.unwrap_or(self.config.drag_sensitivity)) - .clamp(self.min, self.max); + .clamp(0.0, 1.0); + } + } + + *self.value = if self.config.logarithmic_scaling { + remap(10f32.powf(raw), 1.0..=10.0, self.min..=self.max) + }else { + remap(raw, 0.0..=1.0, self.min..=self.max) + }; + + if response.double_clicked() { + if let Some(reset_value) = self.config.reset_value { + *self.value = reset_value } } @@ -222,8 +239,7 @@ impl Widget for Knob<'_> { let center = knob_rect.center(); let radius = self.config.size / 2.0; - let updated_value = *self.value; - let updated_renderer = KnobRenderer::new(&self.config, updated_value, self.min, self.max); + let updated_renderer = KnobRenderer::new(&self.config, *self.value, raw, self.min, self.max); updated_renderer.render_knob(ui.painter(), center, radius, response.hovered()); updated_renderer.render_label(ui, rect);