From 97592c303b24e9d87891cc7440ad48a5e8b485b7 Mon Sep 17 00:00:00 2001
From: Andrew Zonenberg <azonenberg@drawersteak.com>
Date: Tue, 5 Dec 2023 18:57:31 -0800
Subject: [PATCH] WaveformArea: implemented secondary trigger level arrow.
 Fixes #658.

---
 lib                                |  2 +-
 src/ngscopeclient/WaveformArea.cpp | 91 ++++++++++++++++++++++++++++--
 src/ngscopeclient/WaveformArea.h   |  1 +
 3 files changed, 88 insertions(+), 6 deletions(-)

diff --git a/lib b/lib
index e68e00044..14640ce92 160000
--- a/lib
+++ b/lib
@@ -1 +1 @@
-Subproject commit e68e00044fcc5499704a7837cf93c7445fdb570e
+Subproject commit 14640ce92f3493eaa2964864490670e61c73b423
diff --git a/src/ngscopeclient/WaveformArea.cpp b/src/ngscopeclient/WaveformArea.cpp
index 3e6e3bd76..ee8e5c8ff 100644
--- a/src/ngscopeclient/WaveformArea.cpp
+++ b/src/ngscopeclient/WaveformArea.cpp
@@ -2576,13 +2576,41 @@ void WaveformArea::RenderTriggerLevelArrows(ImVec2 start, ImVec2 /*size*/)
 			}
 		}
 
-		//TODO: second level
+		//Second level
 		auto sl = dynamic_cast<TwoLevelTrigger*>(trig);
 		if(sl)
-			LogWarning("Two-level triggers not implemented\n");
+		{
+			//Draw the arrow
+			//If currently dragging, show at mouse position rather than actual hardware trigger level
+			level = sl->GetLowerBound();
+			y = YAxisUnitsToYPosition(level);
+			if( (m_dragState == DRAG_STATE_TRIGGER_SECONDARY_LEVEL) && (trig == m_triggerDuringDrag) )
+				y = mouse.y;
+			arrowtop = y - arrowsize/2;
+			arrowbot = y + arrowsize/2;
+			draw_list->AddTriangleFilled(
+				ImVec2(start.x, y), ImVec2(arrowright, arrowtop), ImVec2(arrowright, arrowbot), color);
+
+			//Check mouse position
+			//Use slightly expanded hitbox to make it easier to capture
+			caparrowtop = y - caparrowsize/2;
+			caparrowbot = y + caparrowsize/2;
+			if( (mouse.x >= start.x) && (mouse.x <= caparrowright) && (mouse.y >= caparrowtop) && (mouse.y <= caparrowbot) )
+			{
+				ImGui::SetMouseCursor(ImGuiMouseCursor_ResizeNS);
+				m_mouseOverTriggerArrow = true;
+
+				if(ImGui::IsMouseClicked(ImGuiMouseButton_Left))
+				{
+					LogTrace("Start dragging secondary trigger level\n");
+					m_dragState = DRAG_STATE_TRIGGER_SECONDARY_LEVEL;
+					m_triggerDuringDrag = trig;
+				}
+			}
+		}
 
 		//Handle dragging
-		if(m_dragState == DRAG_STATE_TRIGGER_LEVEL)
+		if( (m_dragState == DRAG_STATE_TRIGGER_LEVEL) || (m_dragState == DRAG_STATE_TRIGGER_SECONDARY_LEVEL) )
 			m_triggerLevelDuringDrag = YPositionToYAxisUnits(mouse.y);
 	}
 }
@@ -3354,8 +3382,61 @@ void WaveformArea::OnMouseUp()
 				Unit volts(Unit::UNIT_VOLTS);
 				LogTrace("End dragging trigger level (at %s)\n", volts.PrettyPrint(m_triggerLevelDuringDrag).c_str());
 
-				m_triggerDuringDrag->SetLevel(m_triggerLevelDuringDrag);
-				m_triggerDuringDrag->GetScope()->PushTrigger();
+				//If two-level trigger, make sure we have the levels in the right order
+				auto tlt = dynamic_cast<TwoLevelTrigger*>(m_triggerDuringDrag);
+				if(tlt)
+				{
+					//We're dragging the primary level, which should always be higher than the secondary
+					auto sec = tlt->GetLowerBound();
+					if(m_triggerLevelDuringDrag >= sec)
+					{
+						tlt->SetUpperBound(m_triggerLevelDuringDrag);
+						tlt->GetScope()->PushTrigger();
+					}
+
+					//But if we dragged past the secondary level, invert (otherwise we'll never trigger)
+					else
+					{
+						tlt->SetUpperBound(sec);
+						tlt->SetLowerBound(m_triggerLevelDuringDrag);
+						tlt->GetScope()->PushTrigger();
+					}
+				}
+
+				else
+				{
+					m_triggerDuringDrag->SetLevel(m_triggerLevelDuringDrag);
+					m_triggerDuringDrag->GetScope()->PushTrigger();
+				}
+			}
+			break;
+
+		case DRAG_STATE_TRIGGER_SECONDARY_LEVEL:
+			{
+				Unit volts(Unit::UNIT_VOLTS);
+				LogTrace("End dragging secondary trigger level (at %s)\n",
+					volts.PrettyPrint(m_triggerLevelDuringDrag).c_str());
+
+				//If two-level trigger, make sure we have the levels in the right order
+				auto tlt = dynamic_cast<TwoLevelTrigger*>(m_triggerDuringDrag);
+				if(tlt)
+				{
+					//We're dragging the secondary level, which should always be lower than the secondary
+					auto prim = tlt->GetUpperBound();
+					if(m_triggerLevelDuringDrag < prim)
+					{
+						tlt->SetLowerBound(m_triggerLevelDuringDrag);
+						tlt->GetScope()->PushTrigger();
+					}
+
+					//But if we dragged past the secondary level, invert (otherwise we'll never trigger)
+					else
+					{
+						tlt->SetUpperBound(m_triggerLevelDuringDrag);
+						tlt->SetLowerBound(prim);
+						tlt->GetScope()->PushTrigger();
+					}
+				}
 			}
 			break;
 
diff --git a/src/ngscopeclient/WaveformArea.h b/src/ngscopeclient/WaveformArea.h
index 715ac47c4..23866be06 100644
--- a/src/ngscopeclient/WaveformArea.h
+++ b/src/ngscopeclient/WaveformArea.h
@@ -566,6 +566,7 @@ class WaveformArea
 		DRAG_STATE_CHANNEL_LAST,
 		DRAG_STATE_Y_AXIS,
 		DRAG_STATE_TRIGGER_LEVEL,
+		DRAG_STATE_TRIGGER_SECONDARY_LEVEL,
 		DRAG_STATE_BER_LEVEL,
 		DRAG_STATE_BER_BOTH,
 		DRAG_STATE_PEAK_MARKER