From 1f78dac7b55db8ad950122078f8079b15e5897fb Mon Sep 17 00:00:00 2001
From: tetektoza <tetektoza@gmail.com>
Date: Tue, 28 Oct 2025 23:50:43 +0100
Subject: [PATCH] Sketcher: Remember cursor angle for Line OVPs after OVP is
 set

As the title says. Currently user is able to change geometry if OVP is
set on labels. This is because `doEnforceControlParameters` reads mouse
position every mouse move and calculates angle from it, resulting in a
new angle every time mouse is moved.

So, this patch basically reads the position before it was set, and once
it is set, locks the position of the mouse and calculates angle from it
which will be maintained until user cleans the OVP or makes a new
primitive.
---
 src/Mod/Sketcher/Gui/DrawSketchHandlerLine.h | 57 ++++++++++++++++----
 1 file changed, 46 insertions(+), 11 deletions(-)

diff --git a/src/Mod/Sketcher/Gui/DrawSketchHandlerLine.h b/src/Mod/Sketcher/Gui/DrawSketchHandlerLine.h
index 5ff0a6238c..1a2bf0cebd 100644
--- a/src/Mod/Sketcher/Gui/DrawSketchHandlerLine.h
+++ b/src/Mod/Sketcher/Gui/DrawSketchHandlerLine.h
@@ -86,7 +86,10 @@ public:
     explicit DrawSketchHandlerLine(
         ConstructionMethod constrMethod = ConstructionMethod::OnePointLengthAngle)
         : DrawSketchHandlerLineBase(constrMethod)
-        , length(0.0) {};
+        , length(0.0)
+        , lengthSign(0)
+        , widthSign(0)
+        , capturedDirection(0.0, 0.0) {};
     ~DrawSketchHandlerLine() override = default;
 
 private:
@@ -237,10 +240,23 @@ private:
         }
     }
 
+    void onReset() override
+    {
+        lengthSign = 0;
+        widthSign = 0;
+        capturedDirection = Base::Vector2d(0.0, 0.0);
+        toolWidgetManager.resetControls();
+    }
+
 private:
     Base::Vector2d startPoint, endPoint;
     double length;
 
+    // These store the direction sign when OVP is first set to prevent sign flipping
+    int lengthSign, widthSign;
+    // Direction tracking to check once OVP is locked
+    Base::Vector2d capturedDirection;
+
     void createShape(bool onlyeditoutline) override
     {
         Q_UNUSED(onlyeditoutline);
@@ -427,12 +443,17 @@ void DSHLineControllerBase::doEnforceControlParameters(Base::Vector2d& onSketchP
                             if (fabs(width) < Precision::Confusion()
                                 && fourthParam->hasFinishedEditing) {
                                 unsetOnViewParameter(thirdParam.get());
+                                handler->lengthSign = 0;
                                 return;
                             }
                         }
                     }
-                    int sign = (onSketchPos.x - handler->startPoint.x) >= 0 ? 1 : -1;
-                    onSketchPos.x = handler->startPoint.x + sign * length;
+                    // get sign on the first time we set the OVP label, so it won't get flipped
+                    // with mouse next time
+                    if (handler->lengthSign == 0) {
+                        handler->lengthSign = (onSketchPos.x - handler->startPoint.x) >= 0 ? 1 : -1;
+                    }
+                    onSketchPos.x = handler->startPoint.x + handler->lengthSign * length;
                 }
 
                 if (fourthParam->isSet) {
@@ -444,12 +465,15 @@ void DSHLineControllerBase::doEnforceControlParameters(Base::Vector2d& onSketchP
                             if (fabs(length) < Precision::Confusion()
                                 && thirdParam->hasFinishedEditing) {
                                 unsetOnViewParameter(fourthParam.get());
+                                handler->widthSign = 0;
                                 return;
                             }
                         }
                     }
-                    int sign = (onSketchPos.y - handler->startPoint.y) >= 0 ? 1 : -1;
-                    onSketchPos.y = handler->startPoint.y + sign * width;
+                    if (handler->widthSign == 0) {
+                        handler->widthSign = (onSketchPos.y - handler->startPoint.y) >= 0 ? 1 : -1;
+                    }
+                    onSketchPos.y = handler->startPoint.y + handler->widthSign * width;
                 }
             }
             else if (handler->constructionMethod() == ConstructionMethod::OnePointLengthAngle) {
@@ -460,20 +484,29 @@ void DSHLineControllerBase::doEnforceControlParameters(Base::Vector2d& onSketchP
                 }
                 double length = dir.Length();
 
+                if (fourthParam->isSet) {
+                    const double angle = Base::toRadians(fourthParam->getValue());
+                    const Base::Vector2d ovpDir(cos(angle), sin(angle));
+                    handler->capturedDirection = ovpDir;
+                }
+                else {
+                    handler->capturedDirection = dir.Normalize();
+                }
+
                 if (thirdParam->isSet) {
                     length = thirdParam->getValue();
                     if (length < Precision::Confusion() && thirdParam->hasFinishedEditing) {
                         unsetOnViewParameter(thirdParam.get());
+                        handler->capturedDirection = Base::Vector2d(0.0, 0.0);
                         return;
                     }
 
-                    onSketchPos = handler->startPoint + length * dir.Normalize();
+                    onSketchPos = handler->startPoint + length * handler->capturedDirection;
                 }
-
-                if (fourthParam->isSet) {
-                    double angle = Base::toRadians(fourthParam->getValue());
-                    Base::Vector2d ovpDir(cos(angle), sin(angle));
-                    onSketchPos.ProjectToLine(onSketchPos - handler->startPoint, ovpDir);
+                else if (fourthParam->isSet) {
+                    // only angle is set, project current position onto that angle
+                    onSketchPos.ProjectToLine(onSketchPos - handler->startPoint,
+                                              handler->capturedDirection);
                     onSketchPos += handler->startPoint;
                 }
             }
@@ -490,6 +523,8 @@ void DSHLineControllerBase::doEnforceControlParameters(Base::Vector2d& onSketchP
                 && (onSketchPos - handler->startPoint).Length() < Precision::Confusion()) {
                 unsetOnViewParameter(thirdParam.get());
                 unsetOnViewParameter(fourthParam.get());
+                handler->lengthSign = 0;
+                handler->widthSign = 0;
             }
         } break;
         default: