From b23336b5891d4a7b142bde3c9171b100d943da94 Mon Sep 17 00:00:00 2001
From: ruevs <dpr@ruevs.com>
Date: Tue, 27 Oct 2015 12:28:33 +0200
Subject: [PATCH] Add a new length-difference constraint.
This constraint requires the lengths of two line segments to
differ by a constant.
It can be useful to define the tolerances when making joints.
---
exposed/DOC.txt | 4 ++++
exposed/VbDemo.vb | 1 +
include/slvs.h | 1 +
src/constraint.cpp | 18 ++++++++++++++++++
src/constrainteq.cpp | 10 ++++++++++
src/drawconstraint.cpp | 5 ++++-
src/graphicswin.cpp | 1 +
src/lib.cpp | 1 +
src/mouse.cpp | 4 +++-
src/sketch.h | 1 +
src/solvespace.cpp | 3 ++-
src/ui.h | 1 +
12 files changed, 47 insertions(+), 3 deletions(-)
diff --git a/exposed/DOC.txt b/exposed/DOC.txt
index 5b04950..743349b 100644
--- a/exposed/DOC.txt
+++ b/exposed/DOC.txt
@@ -313,6 +313,10 @@ SLVS_C_LENGTH_RATIO*
The length of line entityA divided by the length of line entityB is
equal to valA.
+SLVS_C_LENGTH_DIFFERENCE*
+
+ The lengths of line entityA and line entityB differ by valA.
+
SLVS_C_EQ_LEN_PT_LINE_D*
The length of the line entityA is equal to the distance from point
diff --git a/exposed/VbDemo.vb b/exposed/VbDemo.vb
index 01eafc7..6781fc4 100644
--- a/exposed/VbDemo.vb
+++ b/exposed/VbDemo.vb
@@ -511,6 +511,7 @@ Module VbDemo
Public Const SLVS_C_PROJ_PT_DISTANCE As Integer = 100030
Public Const SLVS_C_WHERE_DRAGGED As Integer = 100031
Public Const SLVS_C_CURVE_CURVE_TANGENT As Integer = 100032
+ Public Const SLVS_C_LENGTH_DIFFERENCE As Integer = 100033
<StructLayout(LayoutKind.Sequential)> Public Structure Slvs_Constraint
Public h As UInteger
diff --git a/include/slvs.h b/include/slvs.h
index a06ac92..3181ceb 100644
--- a/include/slvs.h
+++ b/include/slvs.h
@@ -112,6 +112,7 @@ typedef struct {
#define SLVS_C_PROJ_PT_DISTANCE 100030
#define SLVS_C_WHERE_DRAGGED 100031
#define SLVS_C_CURVE_CURVE_TANGENT 100032
+#define SLVS_C_LENGTH_DIFFERENCE 100033
typedef struct {
Slvs_hConstraint h;
diff --git a/src/constraint.cpp b/src/constraint.cpp
index 8a02397..1627937 100644
--- a/src/constraint.cpp
+++ b/src/constraint.cpp
@@ -24,6 +24,7 @@ char *Constraint::DescriptionString(void) {
case EQ_LEN_PT_LINE_D: s = "eq-length-and-pt-ln-dist"; break;
case EQ_PT_LN_DISTANCES: s = "eq-pt-line-distances"; break;
case LENGTH_RATIO: s = "length-ratio"; break;
+ case LENGTH_DIFFERENCE: s = "length-difference"; break;
case SYMMETRIC: s = "symmetric"; break;
case SYMMETRIC_HORIZ: s = "symmetric-h"; break;
case SYMMETRIC_VERT: s = "symmetric-v"; break;
@@ -322,6 +323,23 @@ void Constraint::MenuConstrain(int id) {
AddConstraint(&c);
break;
+ case GraphicsWindow::MNU_DIFFERENCE:
+ if(gs.lineSegments == 2 && gs.n == 2) {
+ c.type = LENGTH_DIFFERENCE;
+ c.entityA = gs.entity[0];
+ c.entityB = gs.entity[1];
+ } else {
+ Error("Bad selection for length difference constraint. This "
+ "constraint can apply to:\n\n"
+ " * two line segments\n");
+ return;
+ }
+
+ c.valA = 0;
+ c.ModifyToSatisfy();
+ AddConstraint(&c);
+ break;
+
case GraphicsWindow::MNU_AT_MIDPOINT:
if(gs.lineSegments == 1 && gs.points == 1 && gs.n == 2) {
c.type = AT_MIDPOINT;
diff --git a/src/constrainteq.cpp b/src/constrainteq.cpp
index 1c6beb1..5928826 100644
--- a/src/constrainteq.cpp
+++ b/src/constrainteq.cpp
@@ -18,6 +18,7 @@ bool ConstraintBase::HasLabel(void) {
case PROJ_PT_DISTANCE:
case DIAMETER:
case LENGTH_RATIO:
+ case LENGTH_DIFFERENCE:
case ANGLE:
case COMMENT:
return true;
@@ -279,6 +280,15 @@ void ConstraintBase::GenerateReal(IdList<Equation,hEquation> *l) {
break;
}
+ case LENGTH_DIFFERENCE: {
+ EntityBase *a = SK.GetEntity(entityA);
+ EntityBase *b = SK.GetEntity(entityB);
+ Expr *la = Distance(workplane, a->point[0], a->point[1]);
+ Expr *lb = Distance(workplane, b->point[0], b->point[1]);
+ AddEq(l, (la->Minus(lb))->Minus(exA), 0);
+ break;
+ }
+
case DIAMETER: {
EntityBase *circle = SK.GetEntity(entityA);
Expr *r = circle->CircleGetRadiusExpr();
diff --git a/src/drawconstraint.cpp b/src/drawconstraint.cpp
index 391ae5c..82a1708 100644
--- a/src/drawconstraint.cpp
+++ b/src/drawconstraint.cpp
@@ -63,6 +63,8 @@ char *Constraint::Label(void) {
sprintf(Ret, "%.2f", valA);
} else if(type == LENGTH_RATIO) {
sprintf(Ret, "%.3f:1", valA);
+ } else if(type == LENGTH_DIFFERENCE) {
+ sprintf(Ret, "%.3f", valA);
} else if(type == COMMENT) {
strcpy(Ret, comment.str);
} else if(type == DIAMETER) {
@@ -853,6 +855,7 @@ void Constraint::DrawOrGetDistance(Vector *labelPos) {
}
case LENGTH_RATIO:
+ case LENGTH_DIFFERENCE:
case EQUAL_LENGTH_LINES: {
Vector a, b = Vector::From(0, 0, 0);
for(int i = 0; i < 2; i++) {
@@ -867,7 +870,7 @@ void Constraint::DrawOrGetDistance(Vector *labelPos) {
DoEqualLenTicks(a, b, gn);
}
- if(type == LENGTH_RATIO) {
+ if((type == LENGTH_RATIO) || (type == LENGTH_DIFFERENCE)) {
Vector ref = ((a.Plus(b)).ScaledBy(0.5)).Plus(disp.offset);
DoLabel(ref, labelPos, gr, gu);
}
diff --git a/src/graphicswin.cpp b/src/graphicswin.cpp
index 806c32a..a76b3db 100644
--- a/src/graphicswin.cpp
+++ b/src/graphicswin.cpp
@@ -139,6 +139,7 @@ const GraphicsWindow::MenuEntry GraphicsWindow::menu[] = {
{ 1, "&On Point / Curve / Plane", MNU_ON_ENTITY, 'O', IN, mCon },
{ 1, "E&qual Length / Radius / Angle", MNU_EQUAL, 'Q', IN, mCon },
{ 1, "Length Ra&tio", MNU_RATIO, 'Z', IN, mCon },
+{ 1, "Length Diff&erence", MNU_DIFFERENCE, 'J', IN, mCon },
{ 1, "At &Midpoint", MNU_AT_MIDPOINT, 'M', IN, mCon },
{ 1, "S&ymmetric", MNU_SYMMETRIC, 'Y', IN, mCon },
{ 1, "Para&llel / Tangent", MNU_PARALLEL, 'L', IN, mCon },
diff --git a/src/lib.cpp b/src/lib.cpp
index 67fcb09..bf9a81e 100644
--- a/src/lib.cpp
+++ b/src/lib.cpp
@@ -156,6 +156,7 @@ case SLVS_C_EQ_LEN_PT_LINE_D: t = Constraint::EQ_LEN_PT_LINE_D; break;
case SLVS_C_EQ_PT_LN_DISTANCES: t = Constraint::EQ_PT_LN_DISTANCES; break;
case SLVS_C_EQUAL_ANGLE: t = Constraint::EQUAL_ANGLE; break;
case SLVS_C_EQUAL_LINE_ARC_LEN: t = Constraint::EQUAL_LINE_ARC_LEN; break;
+case SLVS_C_LENGTH_DIFFERENCE: t = Constraint::LENGTH_DIFFERENCE; break;
case SLVS_C_SYMMETRIC: t = Constraint::SYMMETRIC; break;
case SLVS_C_SYMMETRIC_HORIZ: t = Constraint::SYMMETRIC_HORIZ; break;
case SLVS_C_SYMMETRIC_VERT: t = Constraint::SYMMETRIC_VERT; break;
diff --git a/src/mouse.cpp b/src/mouse.cpp
index 9803be9..2a8db0e 100644
--- a/src/mouse.cpp
+++ b/src/mouse.cpp
@@ -1155,6 +1155,7 @@ void GraphicsWindow::MouseLeftDoubleClick(double mx, double my) {
case Constraint::ANGLE:
case Constraint::LENGTH_RATIO:
+ case Constraint::LENGTH_DIFFERENCE:
sprintf(s, "%.3f", c->valA);
break;
@@ -1206,7 +1207,8 @@ void GraphicsWindow::EditControlDone(const char *s) {
case Constraint::PROJ_PT_DISTANCE:
case Constraint::PT_LINE_DISTANCE:
case Constraint::PT_FACE_DISTANCE:
- case Constraint::PT_PLANE_DISTANCE: {
+ case Constraint::PT_PLANE_DISTANCE:
+ case Constraint::LENGTH_DIFFERENCE: {
// The sign is not displayed to the user, but this is a signed
// distance internally. To flip the sign, the user enters a
// negative distance.
diff --git a/src/sketch.h b/src/sketch.h
index 6cf61eb..a79f472 100644
--- a/src/sketch.h
+++ b/src/sketch.h
@@ -555,6 +555,7 @@ public:
EQ_PT_LN_DISTANCES = 53,
EQUAL_ANGLE = 54,
EQUAL_LINE_ARC_LEN = 55,
+ LENGTH_DIFFERENCE = 56,
SYMMETRIC = 60,
SYMMETRIC_HORIZ = 61,
SYMMETRIC_VERT = 62,
diff --git a/src/solvespace.cpp b/src/solvespace.cpp
index 94eb385..e255d45 100644
--- a/src/solvespace.cpp
+++ b/src/solvespace.cpp
@@ -560,7 +560,8 @@ void SolveSpaceUI::MenuAnalyze(int id) {
SS.TW.shown.dimSteps = 10;
SS.TW.shown.dimIsDistance =
(c->type != Constraint::ANGLE) &&
- (c->type != Constraint::LENGTH_RATIO);
+ (c->type != Constraint::LENGTH_RATIO) &&
+ (c->type != Constraint::LENGTH_DIFFERENCE);
SS.TW.shown.constraint = c->h;
SS.TW.shown.screen = TextWindow::SCREEN_STEP_DIMENSION;
diff --git a/src/ui.h b/src/ui.h
index 0bb59e7..e068dd0 100644
--- a/src/ui.h
+++ b/src/ui.h
@@ -404,6 +404,7 @@ public:
MNU_REFERENCE,
MNU_EQUAL,
MNU_RATIO,
+ MNU_DIFFERENCE,
MNU_ON_ENTITY,
MNU_SYMMETRIC,
MNU_AT_MIDPOINT,