solvespace/drawconstraint.cpp
Jonathan Westhues e11da119f0 Add point-line distance, point-plane distance, and point-on-circle
constraints. And generate the constraint equations for entities
(e.g., that our unit quaternions have magnitude one). Numerical
troubles there, but it sort of works. Also some stuff to draw
projection lines with projected constraints, and to auto-insert
more constraints as you draw.

[git-p4: depot-paths = "//depot/solvespace/": change = 1711]
2008-05-07 23:30:30 -08:00

361 lines
13 KiB
C++

#include "solvespace.h"
bool Constraint::HasLabel(void) {
switch(type) {
case PT_LINE_DISTANCE:
case PT_PLANE_DISTANCE:
case PT_PT_DISTANCE:
case DIAMETER:
return true;
default:
return false;
}
}
void Constraint::LineDrawOrGetDistance(Vector a, Vector b) {
if(dogd.drawing) {
glBegin(GL_LINE_STRIP);
glxVertex3v(a);
glxVertex3v(b);
glEnd();
} else {
Point2d ap = SS.GW.ProjectPoint(a);
Point2d bp = SS.GW.ProjectPoint(b);
double d = dogd.mp.DistanceToLine(ap, bp.Minus(ap), true);
dogd.dmin = min(dogd.dmin, d);
}
}
double Constraint::EllipticalInterpolation(double rx, double ry, double theta) {
double ex = rx*cos(theta);
double ey = ry*sin(theta);
double v = sqrt(ex*ex + ey*ey);
return v;
}
void Constraint::DoLabel(Vector ref, Vector *labelPos, Vector gr, Vector gu) {
char *s = exprA->Print();
if(labelPos) {
// labelPos is from the top left corner (for the text box used to
// edit things), but ref is from the center.
*labelPos = ref.Minus(gr.WithMagnitude(glxStrWidth(s)/2)).Minus(
gu.WithMagnitude(glxStrHeight()/2));
}
if(dogd.drawing) {
glPushMatrix();
glxTranslatev(ref);
glxOntoWorkplane(gr, gu);
glxWriteTextRefCenter(s);
glPopMatrix();
} else {
Point2d o = SS.GW.ProjectPoint(ref);
dogd.dmin = min(dogd.dmin, o.DistanceTo(dogd.mp) - 10);
}
}
void Constraint::DoProjectedPoint(Vector *r) {
Vector p = r->ProjectInto(workplane);
glLineStipple(4, 0x5555);
glEnable(GL_LINE_STIPPLE);
LineDrawOrGetDistance(p, *r);
glDisable(GL_LINE_STIPPLE);
*r = p;
}
void Constraint::DrawOrGetDistance(Vector *labelPos) {
if(!SS.GW.showConstraints) return;
Group *g = SS.GetGroup(group);
// If the group is hidden, then the constraints are hidden and not
// able to be selected.
if(!(g->visible)) return;
// And likewise if the group is not the active group.
if(g->h.v != SS.GW.activeGroup.v) return;
// Unit vectors that describe our current view of the scene. One pixel
// long, not one actual unit.
Vector gr = SS.GW.projRight.ScaledBy(1/SS.GW.scale);
Vector gu = SS.GW.projUp.ScaledBy(1/SS.GW.scale);
Vector gn = (gr.Cross(gu)).WithMagnitude(1/SS.GW.scale);
glxColor3d(1, 0.2, 1);
switch(type) {
case PT_PT_DISTANCE: {
Vector ap = SS.GetEntity(ptA)->PointGetNum();
Vector bp = SS.GetEntity(ptB)->PointGetNum();
if(workplane.v != Entity::FREE_IN_3D.v) {
DoProjectedPoint(&ap);
DoProjectedPoint(&bp);
}
Vector ref = ((ap.Plus(bp)).ScaledBy(0.5)).Plus(disp.offset);
Vector ab = ap.Minus(bp);
Vector ar = ap.Minus(ref);
// Normal to a plan containing the line and the label origin.
Vector n = ab.Cross(ar);
Vector out = ab.Cross(n).WithMagnitude(1);
out = out.ScaledBy(-out.Dot(ar));
LineDrawOrGetDistance(ap, ap.Plus(out));
LineDrawOrGetDistance(bp, bp.Plus(out));
DoLabel(ref, labelPos, gr, gu);
break;
}
case PT_PLANE_DISTANCE: {
Vector pt = SS.GetEntity(ptA)->PointGetNum();
Entity *plane = SS.GetEntity(entityA);
Vector n = plane->Normal()->NormalN();
Vector p = plane->WorkplaneGetOffset();
double d = (p.Minus(pt)).Dot(n);
Vector closest = pt.Plus(n.WithMagnitude(d));
LineDrawOrGetDistance(pt, closest);
Vector ref = ((closest.Plus(pt)).ScaledBy(0.5)).Plus(disp.offset);
DoLabel(ref, labelPos, gr, gu);
break;
}
case PT_LINE_DISTANCE: {
Vector pt = SS.GetEntity(ptA)->PointGetNum();
Entity *line = SS.GetEntity(entityA);
Vector lA = SS.GetEntity(line->point[0])->PointGetNum();
Vector lB = SS.GetEntity(line->point[1])->PointGetNum();
if(workplane.v != Entity::FREE_IN_3D.v) {
lA = lA.ProjectInto(workplane);
lB = lB.ProjectInto(workplane);
DoProjectedPoint(&pt);
}
Vector lAB = (lA.Minus(lB)).WithMagnitude(1);
Vector closest;
// lA, lB, and pt define a plane; the min distance is in
// that plane, so calculate its normal
Vector pn = (pt.Minus(lA)).Cross(lAB);
// The minimum distance line is in that plane, perpendicular
// to the line
Vector n = pn.Cross(lAB);
// Calculate the actual distance
double d = (lAB.Cross(lA.Minus(pt))).Magnitude();
closest = pt.Plus(n.WithMagnitude(d));
LineDrawOrGetDistance(pt, closest);
Vector ref = ((closest.Plus(pt)).ScaledBy(0.5)).Plus(disp.offset);
DoLabel(ref, labelPos, gr, gu);
break;
}
case DIAMETER: {
Entity *circle = SS.GetEntity(entityA);
Vector center = SS.GetEntity(circle->point[0])->PointGetNum();
double r = SS.GetEntity(circle->distance)->DistanceGetNum();
Vector ref = center.Plus(disp.offset);
double theta = atan2(disp.offset.Dot(gu), disp.offset.Dot(gr));
double adj = EllipticalInterpolation(
glxStrWidth(exprA->Print())/2, glxStrHeight()/2, theta);
Vector mark = ref.Minus(center);
mark = mark.WithMagnitude(mark.Magnitude()-r);
LineDrawOrGetDistance(ref.Minus(mark.WithMagnitude(adj)),
ref.Minus(mark));
DoLabel(ref, labelPos, gr, gu);
break;
}
case POINTS_COINCIDENT: {
if(!dogd.drawing) {
for(int i = 0; i < 2; i++) {
Vector p = SS.GetEntity(i == 0 ? ptA : ptB)-> PointGetNum();
Point2d pp = SS.GW.ProjectPoint(p);
// The point is selected within a radius of 7, from the
// same center; so if the point is visible, then this
// constraint cannot be selected. But that's okay.
dogd.dmin = min(dogd.dmin, pp.DistanceTo(dogd.mp) - 3);
}
break;
}
for(int a = 0; a < 2; a++) {
Vector r = SS.GW.projRight.ScaledBy((a+1)/SS.GW.scale);
Vector d = SS.GW.projUp.ScaledBy((2-a)/SS.GW.scale);
for(int i = 0; i < 2; i++) {
Vector p = SS.GetEntity(i == 0 ? ptA : ptB)-> PointGetNum();
glxColor3d(0.4, 0, 0.4);
glBegin(GL_QUADS);
glxVertex3v(p.Plus (r).Plus (d));
glxVertex3v(p.Plus (r).Minus(d));
glxVertex3v(p.Minus(r).Minus(d));
glxVertex3v(p.Minus(r).Plus (d));
glEnd();
}
}
break;
}
case PT_ON_CIRCLE:
case PT_ON_LINE:
case PT_IN_PLANE: {
double s = 7/SS.GW.scale;
Vector p = SS.GetEntity(ptA)->PointGetNum();
Vector r = gr.WithMagnitude(s);
Vector d = gu.WithMagnitude(s);
LineDrawOrGetDistance(p.Plus (r).Plus (d), p.Plus (r).Minus(d));
LineDrawOrGetDistance(p.Plus (r).Minus(d), p.Minus(r).Minus(d));
LineDrawOrGetDistance(p.Minus(r).Minus(d), p.Minus(r).Plus (d));
LineDrawOrGetDistance(p.Minus(r).Plus (d), p.Plus (r).Plus (d));
break;
}
case EQUAL_LENGTH_LINES: {
for(int i = 0; i < 2; i++) {
Entity *e = SS.GetEntity(i == 0 ? entityA : entityB);
Vector a = SS.GetEntity(e->point[0])->PointGetNum();
Vector b = SS.GetEntity(e->point[1])->PointGetNum();
Vector m = (a.ScaledBy(1.0/3)).Plus(b.ScaledBy(2.0/3));
Vector ab = a.Minus(b);
Vector n = (gn.Cross(ab)).WithMagnitude(10/SS.GW.scale);
LineDrawOrGetDistance(m.Minus(n), m.Plus(n));
}
break;
}
case SYMMETRIC: {
Vector a = SS.GetEntity(ptA)->PointGetNum();
Vector b = SS.GetEntity(ptB)->PointGetNum();
Vector n = SS.GetEntity(entityA)->Normal()->NormalN();
for(int i = 0; i < 2; i++) {
Vector tail = (i == 0) ? a : b;
Vector d = (i == 0) ? b : a;
d = d.Minus(tail);
// Project the direction in which the arrow is drawn normal
// to the symmetry plane; for projected symmetry constraints,
// they might not be in the same direction, even when the
// constraint is fully solved.
d = n.ScaledBy(d.Dot(n));
d = d.WithMagnitude(20/SS.GW.scale);
Vector tip = tail.Plus(d);
LineDrawOrGetDistance(tail, tip);
d = d.WithMagnitude(9/SS.GW.scale);
LineDrawOrGetDistance(tip, tip.Minus(d.RotatedAbout(gn, 0.6)));
LineDrawOrGetDistance(tip, tip.Minus(d.RotatedAbout(gn, -0.6)));
}
break;
}
case AT_MIDPOINT:
case HORIZONTAL:
case VERTICAL:
if(entityA.v) {
Vector r, u, n;
if(workplane.v == Entity::FREE_IN_3D.v) {
r = gr; u = gu; n = gn;
} else {
r = SS.GetEntity(workplane)->Normal()->NormalU();
u = SS.GetEntity(workplane)->Normal()->NormalV();
n = r.Cross(u);
}
// For "at midpoint", this branch is always taken.
Entity *e = SS.GetEntity(entityA);
Vector a = SS.GetEntity(e->point[0])->PointGetNum();
Vector b = SS.GetEntity(e->point[1])->PointGetNum();
Vector m = (a.ScaledBy(0.5)).Plus(b.ScaledBy(0.5));
Vector offset = (a.Minus(b)).Cross(n);
offset = offset.WithMagnitude(13/SS.GW.scale);
// Draw midpoint constraint on other side of line, so that
// a line can be midpoint and horizontal at same time.
if(type == AT_MIDPOINT) offset = offset.ScaledBy(-1);
if(dogd.drawing) {
glPushMatrix();
glxTranslatev(m.Plus(offset));
glxOntoWorkplane(r, u);
glxWriteTextRefCenter(
(type == HORIZONTAL) ? "H" : (
(type == VERTICAL) ? "V" : (
(type == AT_MIDPOINT) ? "M" : NULL)));
glPopMatrix();
} else {
Point2d ref = SS.GW.ProjectPoint(m.Plus(offset));
dogd.dmin = min(dogd.dmin, ref.DistanceTo(dogd.mp)-10);
}
} else {
Vector a = SS.GetEntity(ptA)->PointGetNum();
Vector b = SS.GetEntity(ptB)->PointGetNum();
Entity *w = SS.GetEntity(SS.GetEntity(ptA)->workplane);
Vector cu = w->Normal()->NormalU();
Vector cv = w->Normal()->NormalV();
Vector cn = w->Normal()->NormalN();
int i;
for(i = 0; i < 2; i++) {
Vector o = (i == 0) ? a : b;
Vector oo = (i == 0) ? a.Minus(b) : b.Minus(a);
Vector d = (type == HORIZONTAL) ? cu : cv;
if(oo.Dot(d) < 0) d = d.ScaledBy(-1);
Vector dp = cn.Cross(d);
d = d.WithMagnitude(14/SS.GW.scale);
Vector c = o.Minus(d);
LineDrawOrGetDistance(o, c);
d = d.WithMagnitude(3/SS.GW.scale);
dp = dp.WithMagnitude(2/SS.GW.scale);
if(dogd.drawing) {
glBegin(GL_QUADS);
glxVertex3v((c.Plus(d)).Plus(dp));
glxVertex3v((c.Minus(d)).Plus(dp));
glxVertex3v((c.Minus(d)).Minus(dp));
glxVertex3v((c.Plus(d)).Minus(dp));
glEnd();
} else {
Point2d ref = SS.GW.ProjectPoint(c);
dogd.dmin = min(dogd.dmin, ref.DistanceTo(dogd.mp)-6);
}
}
}
break;
default: oops();
}
}
void Constraint::Draw(void) {
dogd.drawing = true;
DrawOrGetDistance(NULL);
}
double Constraint::GetDistance(Point2d mp) {
dogd.drawing = false;
dogd.mp = mp;
dogd.dmin = 1e12;
DrawOrGetDistance(NULL);
return dogd.dmin;
}
Vector Constraint::GetLabelPos(void) {
dogd.drawing = false;
dogd.mp.x = 0; dogd.mp.y = 0;
dogd.dmin = 1e12;
Vector p;
DrawOrGetDistance(&p);
return p;
}