From 012903fbf478d32a0beeec93f9b9b81ca041dd40 Mon Sep 17 00:00:00 2001
From: Ryzerth <whatsthetgeek@gmail.com>
Date: Mon, 30 Aug 2021 19:22:00 +0200
Subject: [PATCH] Fixed wrong bandwidth when zooming

---
 core/src/core.cpp            |  2 +-
 core/src/gui/main_window.cpp | 16 +++++++++-------
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/core/src/core.cpp b/core/src/core.cpp
index 2c2f7baf..0a880528 100644
--- a/core/src/core.cpp
+++ b/core/src/core.cpp
@@ -78,7 +78,7 @@ namespace core {
         gui::waterfall.setViewOffset(0);
         gui::waterfall.setViewBandwidth(effectiveSr);
         sigpath::signalPath.setSampleRate(effectiveSr);
-        gui::mainWindow.setViewBandwidthSlider(effectiveSr);
+        gui::mainWindow.setViewBandwidthSlider(1.0);
     }
 };
 
diff --git a/core/src/gui/main_window.cpp b/core/src/gui/main_window.cpp
index d99ffba3..103b2a7c 100644
--- a/core/src/gui/main_window.cpp
+++ b/core/src/gui/main_window.cpp
@@ -176,7 +176,7 @@ void MainWindow::init() {
     gui::freqSelect.frequencyChanged = false;
     sigpath::sourceManager.tune(frequency);
     gui::waterfall.setCenterFrequency(frequency);
-    bw = gui::waterfall.getBandwidth();
+    bw = 1.0;
     gui::waterfall.vfoFreqChanged = false;
     gui::waterfall.centerFreqMoved = false;
     gui::waterfall.selectFirstVFO();
@@ -598,12 +598,14 @@ void MainWindow::draw() {
     ImGui::SetCursorPosX((ImGui::GetWindowSize().x / 2.0) - (ImGui::CalcTextSize("Zoom").x / 2.0));
     ImGui::Text("Zoom");
     ImGui::SetCursorPosX((ImGui::GetWindowSize().x / 2.0) - 10);
-    float minSliderBw = 1000.0;
-    float maxSliderBw = gui::waterfall.getBandwidth();
-    if (ImGui::VSliderFloat("##_7_", ImVec2(20.0, 150.0), &bw, maxSliderBw, minSliderBw, "")) {
-        float normBw = bw / (maxSliderBw - minSliderBw);
-        float factor = normBw * normBw;
-        float finalBw = minSliderBw + bw * factor;
+    if (ImGui::VSliderFloat("##_7_", ImVec2(20.0, 150.0), &bw, 1.0, 0.0, "")) {
+        double factor = (double)bw * (double)bw;
+        
+        // Map 0.0 -> 1.0 to 1000.0 -> bandwidth
+        double delta = gui::waterfall.getBandwidth() - 1000.0;
+        double finalBw = 1000.0 + (factor * delta);
+
+        spdlog::warn("{0} {1} {2}", bw, factor, finalBw);
 
         gui::waterfall.setViewBandwidth(finalBw);
         if (vfo != NULL) {