From dfa1b94c834632bbdada170168cd463efade08fa Mon Sep 17 00:00:00 2001
From: PaddleStroke <pierrelouis.boyer@gmail.com>
Date: Mon, 12 Feb 2024 11:00:52 +0100
Subject: [PATCH] Sketcher: Line DSH: Harmonize width/length behavior with
 rectangle.

---
 src/Mod/Sketcher/Gui/DrawSketchHandlerLine.h | 46 +++++++++++++++-----
 1 file changed, 36 insertions(+), 10 deletions(-)

diff --git a/src/Mod/Sketcher/Gui/DrawSketchHandlerLine.h b/src/Mod/Sketcher/Gui/DrawSketchHandlerLine.h
index b47462e8bf..068cd814f6 100644
--- a/src/Mod/Sketcher/Gui/DrawSketchHandlerLine.h
+++ b/src/Mod/Sketcher/Gui/DrawSketchHandlerLine.h
@@ -357,13 +357,37 @@ void DSHLineControllerBase::doEnforceControlParameters(Base::Vector2d& onSketchP
         case SelectMode::SeekSecond: {
             if (handler->constructionMethod() == ConstructionMethod::OnePointWidthHeight) {
                 if (onViewParameters[OnViewParameter::Third]->isSet) {
-                    onSketchPos.x = handler->startPoint.x
-                        + onViewParameters[OnViewParameter::Third]->getValue();
+                    double length = onViewParameters[OnViewParameter::Third]->getValue();
+                    if (fabs(length) < Precision::Confusion()) {
+                        // Both cannot be 0
+                        if (onViewParameters[OnViewParameter::Fourth]->isSet) {
+                            double width = onViewParameters[OnViewParameter::Fourth]->getValue();
+                            if (fabs(width) < Precision::Confusion()) {
+                                unsetOnViewParameter(
+                                    onViewParameters[OnViewParameter::Third].get());
+                                return;
+                            }
+                        }
+                    }
+                    int sign = (onSketchPos.x - handler->startPoint.x) >= 0 ? 1 : -1;
+                    onSketchPos.x = handler->startPoint.x + sign * length;
                 }
 
                 if (onViewParameters[OnViewParameter::Fourth]->isSet) {
-                    onSketchPos.y = handler->startPoint.y
-                        + onViewParameters[OnViewParameter::Fourth]->getValue();
+                    double width = onViewParameters[OnViewParameter::Fourth]->getValue();
+                    if (fabs(width) < Precision::Confusion()) {
+                        // Both cannot be 0
+                        if (onViewParameters[OnViewParameter::Third]->isSet) {
+                            double length = onViewParameters[OnViewParameter::Third]->getValue();
+                            if (fabs(length) < Precision::Confusion()) {
+                                unsetOnViewParameter(
+                                    onViewParameters[OnViewParameter::Fourth].get());
+                                return;
+                            }
+                        }
+                    }
+                    int sign = (onSketchPos.y - handler->startPoint.y) >= 0 ? 1 : -1;
+                    onSketchPos.y = handler->startPoint.y + sign * width;
                 }
             }
             else if (handler->constructionMethod() == ConstructionMethod::OnePointLengthAngle) {
@@ -440,11 +464,11 @@ void DSHLineController::adaptParameters(Base::Vector2d onSketchPos)
                 Base::Vector3d vec = end - start;
 
                 if (!onViewParameters[OnViewParameter::Third]->isSet) {
-                    setOnViewParameterValue(OnViewParameter::Third, vec.x);
+                    setOnViewParameterValue(OnViewParameter::Third, fabs(vec.x));
                 }
 
                 if (!onViewParameters[OnViewParameter::Fourth]->isSet) {
-                    setOnViewParameterValue(OnViewParameter::Fourth, vec.y);
+                    setOnViewParameterValue(OnViewParameter::Fourth, fabs(vec.y));
                 }
 
                 bool sameSign = vec.x * vec.y > 0.;
@@ -570,12 +594,13 @@ void DSHLineController::addConstraints()
                                   firstCurve);
         }
         else {
+            bool reverse = (handler->endPoint.x - handler->startPoint.x) < 0;
             Gui::cmdAppObjectArgs(obj,
                                   "addConstraint(Sketcher.Constraint('DistanceX',%d,%d,%d,%d,%f)) ",
                                   firstCurve,
-                                  1,
+                                  reverse ? 2 : 1,
                                   firstCurve,
-                                  2,
+                                  reverse ? 1 : 2,
                                   fabs(p3));
         }
     };
@@ -601,12 +626,13 @@ void DSHLineController::addConstraints()
                                   firstCurve);
         }
         else {
+            bool reverse = (handler->endPoint.y - handler->startPoint.y) < 0;
             Gui::cmdAppObjectArgs(obj,
                                   "addConstraint(Sketcher.Constraint('DistanceY',%d,%d,%d,%d,%f)) ",
                                   firstCurve,
-                                  1,
+                                  reverse ? 2 : 1,
                                   firstCurve,
-                                  2,
+                                  reverse ? 1 : 2,
                                   fabs(p4));
         }
     };