MainWindow/Dialog: prevent mouse cursor from obscuring tooltip text

Author: azonenberg

lib

@@ -32,4 +32,5 @@ We try to maintain compatibility with older versions of ngscopeclient but occasi
 
 ## Other changes since v0.1.1
 
-* General UI overhaul of stream browser to make things more intuitive and reduce the number of clicks needed to perform common tasks
+* GUI: General UI overhaul of stream browser to make things more intuitive and reduce the number of clicks needed to perform common tasks
+* GUI: Adjusted tooltip layout code to prevent mouse cursor from blocking the first character of a tooltip

release-notes/CHANGELOG.md

@@ -2,7 +2,7 @@
 *                                                                                                                      *
 * ngscopeclient                                                                                                        *
 *                                                                                                                      *
-* Copyright (c) 2012-2025 Andrew D. Zonenberg and contributors                                                         *
+* Copyright (c) 2012-2026 Andrew D. Zonenberg and contributors                                                         *
 * All rights reserved.                                                                                                 *
 *                                                                                                                      *
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the     *
@@ -34,6 +34,7 @@
  */
 #include "ngscopeclient.h"
 #include "Dialog.h"
+#include "MainWindow.h"
 
 using namespace std;
 
@@ -185,6 +186,8 @@ void Dialog::Tooltip(const string& str, bool allowDisabled)
 
 	if(ImGui::IsItemHovered(ImGuiHoveredFlags_DelayShort | extraFlags))
 	{
+		MainWindow::SetTooltipPosition();
+
 		ImGui::BeginTooltip();
 		ImGui::PushTextWrapPos(ImGui::GetFontSize() * 50);
 		ImGui::TextUnformatted(str.c_str());
@@ -202,6 +205,8 @@ void Dialog::HelpMarker(const string& header, const vector<string>& bullets)
 	ImGui::TextDisabled("(?)");
 	if(ImGui::IsItemHovered(ImGuiHoveredFlags_DelayShort))
 	{
+		MainWindow::SetTooltipPosition();
+
 		ImGui::BeginTooltip();
 		ImGui::PushTextWrapPos(ImGui::GetFontSize() * 50);
 		ImGui::TextUnformatted(header.c_str());

src/ngscopeclient/Dialog.cpp

@@ -137,6 +137,13 @@ class MainWindow : public VulkanWindow
 
 	void OnCursorMoved(int64_t offset);
 
+	///@brief Helper for making sure tooltips aren't obscured by the mouse
+	static void SetTooltipPosition()
+	{
+		auto pos = ImGui::GetIO().MousePos;
+		ImGui::SetNextWindowPos(ImVec2(pos.x + ImGui::GetFontSize(), pos.y), ImGuiCond_Always, ImVec2(0.0, 0.5));
+	}
+
 	void NavigateToTimestamp(
 		int64_t stamp,
 		int64_t duration = 0,

src/ngscopeclient/MainWindow.h

@@ -2971,6 +2971,7 @@ void WaveformArea::RenderEyePatternTooltip(ImVec2 start, ImVec2 size)
 		}
 		auto ber = eyedata->GetBERAtPoint(delta.x, delta.y, eyedata->GetWidth() / 2, ymid);
 
+		MainWindow::SetTooltipPosition();
 		ImGui::BeginTooltip();
 		ImGui::PushTextWrapPos(ImGui::GetFontSize() * 50);
 
@@ -3916,6 +3917,7 @@ void WaveformArea::ChannelButton(shared_ptr<DisplayedChannel> chan, size_t index
 		}
 		tooltip = Trim(tooltip);
 
+		MainWindow::SetTooltipPosition();
 		ImGui::BeginTooltip();
 		ImGui::PushTextWrapPos(ImGui::GetFontSize() * 50);
 		ImGui::TextUnformatted(tooltip.c_str());