From 00e7eae6f869d3c3d702df926a085e82200e4ea3 Mon Sep 17 00:00:00 2001
From: Ajinkya Dahale <AjinkyaDahale@users.noreply.github.com>
Date: Sun, 19 Jun 2022 21:35:24 +0530
Subject: [PATCH] [Sketcher] Use more segments while drawing splines

B-Splines can have an arbitrary number of pieces. Using the same number of
segments to draw a multi-piece spline can make the curve blocky.

This commit only changes the behavior in edit-mode.
---
 .../Gui/EditModeGeometryCoinConverter.cpp     | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/src/Mod/Sketcher/Gui/EditModeGeometryCoinConverter.cpp b/src/Mod/Sketcher/Gui/EditModeGeometryCoinConverter.cpp
index aa797cf277..212e2f0502 100644
--- a/src/Mod/Sketcher/Gui/EditModeGeometryCoinConverter.cpp
+++ b/src/Mod/Sketcher/Gui/EditModeGeometryCoinConverter.cpp
@@ -284,9 +284,13 @@ void EditModeGeometryCoinConverter::convert(const Sketcher::GeometryFacade * geo
         Index[coinLayer].push_back(2);
     }
     else if constexpr (curvemode == CurveMode::ClosedCurve) {
-        double segment = (geo->getLastParameter() - geo->getFirstParameter()) / drawingParameters.curvedEdgeCountSegments;
+        int numSegments = drawingParameters.curvedEdgeCountSegments;
+        if constexpr (std::is_same<GeoType, Part::GeomBSplineCurve>::value)
+            numSegments *= geo->countKnots();
 
-        for (int i=0; i < drawingParameters.curvedEdgeCountSegments; i++) {
+        double segment = (geo->getLastParameter() - geo->getFirstParameter()) / numSegments;
+
+        for (int i=0; i < numSegments; i++) {
             Base::Vector3d pnt = geo->value(i*segment);
             addPoint(Coords[coinLayer], pnt);
         }
@@ -294,13 +298,16 @@ void EditModeGeometryCoinConverter::convert(const Sketcher::GeometryFacade * geo
         Base::Vector3d pnt = geo->value(0);
         addPoint(Coords[coinLayer], pnt);
 
-        Index[coinLayer].push_back(drawingParameters.curvedEdgeCountSegments+1);
+        Index[coinLayer].push_back(numSegments+1);
     }
     else if constexpr (curvemode == CurveMode::OpenCurve) {
+        int numSegments = drawingParameters.curvedEdgeCountSegments;
+        if constexpr (std::is_same<GeoType, Part::GeomBSplineCurve>::value)
+            numSegments *= (geo->countKnots() - 1); // one less segments than knots
 
-        double segment = (geo->getLastParameter() - geo->getFirstParameter()) / drawingParameters.curvedEdgeCountSegments;
+        double segment = (geo->getLastParameter() - geo->getFirstParameter()) / numSegments;
 
-        for (int i=0; i < drawingParameters.curvedEdgeCountSegments; i++) {
+        for (int i=0; i < numSegments; i++) {
             Base::Vector3d pnt = geo->value(geo->getFirstParameter() + i*segment);
             addPoint(Coords[coinLayer], pnt);
         }
@@ -308,7 +315,7 @@ void EditModeGeometryCoinConverter::convert(const Sketcher::GeometryFacade * geo
         Base::Vector3d pnt = geo->value(geo->getLastParameter());
             addPoint(Coords[coinLayer], pnt);
 
-        Index[coinLayer].push_back(drawingParameters.curvedEdgeCountSegments+1);
+        Index[coinLayer].push_back(numSegments+1);
 
         if constexpr (analysemode == AnalyseMode::BoundingBoxMagnitudeAndBSplineCurvature) {
             //***************************************************************************************************************