VolumeBar

Arona/widget/arona_widget.cpp

@@ -4,7 +4,7 @@
 
 using namespace ImGui;
 
-void draw_volume_bar(float volume, float peak, const ImVec2& size_arg, const char* label) {
+void draw_volume_bar(float volume_dB, float peak_dB, const ImVec2& size_arg, const char* label) {
     ImGuiWindow* window = GetCurrentWindow();
     if (window->SkipItems)
         return;
@@ -21,19 +21,24 @@ void draw_volume_bar(float volume, float peak, const ImVec2& size_arg, const cha
 
     window->DrawList->PushClipRect(bb.Min, bb.Max, true);
     // Render
-    volume = ImSaturate(volume);
+    // volume_dB = ImSaturate(volume_dB);
     RenderFrame(bb.Min, bb.Max, GetColorU32(ImGuiCol_FrameBg), true, style.FrameRounding);
     bb.Expand(ImVec2(-style.FrameBorderSize, -style.FrameBorderSize));
 
-    const float y = bb.Max.y - ImLerp(0.0f, size.y, volume);
+    const float y_indicator = map_db_to_non_linear_volume_indicator(volume_dB, -90.0f, 12.0f, 0.0f, size.y);
+
+    // const float y = bb.Max.y - ImLerp(0.0f, size.y, volume_dB);
+    const float y = bb.Max.y - y_indicator;
 
     const ImVec2 fill_min = ImVec2(bb.Min.x, y);
     const ImVec2 fill_br = ImVec2(bb.Max.x, bb.Max.y);
     window->DrawList->AddRectFilled(fill_min, fill_br, GetColorU32(ImGuiCol_PlotHistogram));
 
     // Peak
-    if (peak > 0.0f) {
-        const float peak_y = bb.Max.y - ImLerp(0.0f, size.y, peak);
+    if (peak_dB > -90.f) {
+        const float peak_y_indicator = map_db_to_non_linear_volume_indicator(peak_dB, -90.0f, 12.0f, 0.0f, size.y);
+        // const float peak_y = bb.Max.y - ImLerp(0.0f, size.y, peak_dB);
+        const float peak_y = bb.Max.y - peak_y_indicator;
         if (peak_y < fill_min.y + 1.0f) // Draw line at the top of the fill
             window->DrawList->AddLine(ImVec2(bb.Min.x, peak_y), ImVec2(bb.Max.x, peak_y), GetColorU32(ImGuiCol_Text));
     }

Arona/widget/arona_widget.h

@@ -2,4 +2,55 @@
 
 #include "imgui.h"
 
-void draw_volume_bar(float volume, float peak, const ImVec2& size_arg, const char* label);
+void draw_volume_bar(float volume_dB, float peak_dB, const ImVec2& size_arg, const char* label);
+
+// 计算RMS值
+inline float calculate_rms(const std::vector<float>& samples) {
+    float sum = 0.0;
+    for (const float sample : samples) {
+        sum += sample * sample;
+    }
+    return std::sqrt(sum / samples.size());
+}
+
+// 将RMS值转换为dB
+inline float rms_2_db(float rms, float rms_ref) {
+    return 20.0 * std::log10(rms / rms_ref);
+}
+
+template<class T, class T2>
+static constexpr inline auto get_range_pct(T min_value, T max_value, T2 in_value)
+{
+    // Avoid Divide by Zero.
+    // But also if our range is a point, output whether Value is before or after.
+    const T divisor = max_value - min_value;
+
+    if (divisor == 0)
+    {
+        using RetType = decltype(T() / T2());
+        return (in_value >= max_value) ? (RetType)1 : (RetType)0;
+    }
+
+    return (in_value - min_value) / divisor;
+}
+
+// 对数映射分贝值到非线性音量指示器
+inline float map_db_to_non_linear_volume_indicator(float dB, const float min_db, const float max_db, const float min_indicator, const float max_indicator) {
+    // 确保dB值在合理范围内
+    dB = std::max(min_db, std::min(dB, max_db));
+
+    // 转换dB值为正数，以便于映射，并计算指数
+    const float normalized_db = dB - min_db;
+    const float normalized_max_db = max_db - min_db;
+
+    // 计算对数映射的指数部分
+    const float exp_value = normalized_db == 0 ? 0 : (log10(normalized_db) / log10(normalized_max_db));
+
+    // 映射到指示器范围
+    float indicator_value = exp_value * (max_indicator - min_indicator) + min_indicator;
+
+    // 确保指示器值在合理范围内
+    indicator_value = std::max(min_indicator, std::min(indicator_value, max_indicator));
+
+    return indicator_value;
+}

Arona/widget/widget_mixer.cpp

@@ -8,6 +8,9 @@
 widget_mixer_track::widget_mixer_track(mixer_track* in_mixer_track): mixer_track_(in_mixer_track) {
     name_ = mixer_track_->get_name();
     peak_.resize(in_mixer_track->buffer.get_num_channels());
+    for (auto& p: peak_) {
+        p = -90.f;
+    }
     peak_decay_.resize(in_mixer_track->buffer.get_num_channels());
 }
 
@@ -26,15 +29,20 @@ void widget_mixer_track::on_paint(ImGuiIO& io) {
         for (uint32_t i = 0; i < mixer_track_->ui_buffers.size(); i++) {
             auto& bu_buffer = mixer_track_->ui_buffers[i];
             sample_count = std::min(sample_count, bu_buffer.Num());
-            float temp_max = 0.f;
-            for (int i = 0; i < sample_count; ++i) {
-                float sample = bu_buffer.Pop();
-                temp_max = std::max(temp_max, std::abs(sample));
-            }
+            // float temp_max = 0.f;
+            std::vector<float> samples(sample_count);
+            bu_buffer.Pop(samples.data(), sample_count);
+            const float rms = calculate_rms(samples);
+            const float dB = rms_2_db(rms, 1.0f);
+            // for (uint32_t i = 0; i < sample_count; ++i) {
+            //     temp_max = std::max(temp_max, std::abs(samples[i]));
+            // }
 
-            update_peak(i, temp_max, io.DeltaTime);
+            update_peak(i, dB, io.DeltaTime);
 
-            draw_volume_bar(temp_max, peak_[i], ImVec2(5.0f, 100.0f), "");
+            // const float peak = get_range_pct(-90.0f, 6.0f, peak_[i]);
+
+            draw_volume_bar(dB, peak_[i], ImVec2(5.0f, 100.0f), "");
             ImGui::SameLine();
         }
     }
@@ -50,8 +58,8 @@ void widget_mixer_track::update_peak(uint32_t channel, float new_peak, float del
     }
     current_decay -= delta_time;
     if (current_decay < 0.0f) {
-        current_peak -= delta_time * 0.5f;
-        current_peak = std::max(current_peak, 0.0f);
+        current_peak -= delta_time * 30.f;
+        current_peak = std::max(current_peak, -120.f);
     }
 }