if(h.isFromRequest()) {

Request *r = SK.GetRequest(h.request());

return r->DescriptionString();

} else {

Group *g = SK.GetGroup(h.group());

return g->DescriptionString();

}

SBezierList *sbl = GetOrGenerateBezierCurves();

for(int i = 0; i < sbl->l.n; i++) {

SBezier *sb = &(sbl->l[i]);

List<Vector> lv = {};

sb->MakePwlInto(&lv);

for(int j = 1; j < lv.n; j++) {

el->AddEdge(lv[j-1], lv[j], style.v, i);

}

lv.Clear();

}

SBezierList *sbl = GetOrGenerateBezierCurves();

// We don't bother with bounding boxes for workplanes, etc.

*hasBBox = (IsPoint() || IsNormal() || !sbl->l.IsEmpty());

if(!*hasBBox) return {};

if(screenBBoxValid)

return screenBBox;

if(IsPoint()) {

Vector proj = SS.GW.ProjectPoint3(PointGetNum());

screenBBox = BBox::From(proj, proj);

} else if(IsNormal()) {

Vector proj = SK.GetEntity(point[0])->PointGetNum();

screenBBox = BBox::From(proj, proj);

} else if(!sbl->l.IsEmpty()) {

Vector first = SS.GW.ProjectPoint3(sbl->l[0].ctrl[0]);

screenBBox = BBox::From(first, first);

for(auto &sb : sbl->l) {

for(int i = 0; i < sb.deg; ++i) { screenBBox.Include(SS.GW.ProjectPoint3(sb.ctrl[i])); }

}

} else

ssassert(false, "Expected entity to be a point or have beziers");

screenBBoxValid = true;

return screenBBox;

switch(type) {

case Type::POINT_N_COPY:

case Type::POINT_N_TRANS:

case Type::POINT_N_ROT_TRANS:

case Type::POINT_N_ROT_AA:

case Type::POINT_N_ROT_AXIS_TRANS:

case Type::POINT_IN_3D:

case Type::POINT_IN_2D:

refs->push_back(PointGetNum());

break;

case Type::NORMAL_N_COPY:

case Type::NORMAL_N_ROT:

case Type::NORMAL_N_ROT_AA:

case Type::NORMAL_IN_3D:

case Type::NORMAL_IN_2D:

case Type::WORKPLANE:

case Type::CIRCLE:

case Type::ARC_OF_CIRCLE:

case Type::CUBIC:

case Type::CUBIC_PERIODIC:

case Type::TTF_TEXT:

case Type::IMAGE:

refs->push_back(SK.GetEntity(point[0])->PointGetNum());

break;

case Type::LINE_SEGMENT: {

Vector a = SK.GetEntity(point[0])->PointGetNum(),

b = SK.GetEntity(point[1])->PointGetNum();

refs->push_back(b.Plus(a.Minus(b).ScaledBy(0.5)));

break;

}

case Type::DISTANCE:

case Type::DISTANCE_N_COPY:

case Type::FACE_NORMAL_PT:

case Type::FACE_XPROD:

case Type::FACE_N_ROT_TRANS:

case Type::FACE_N_TRANS:

case Type::FACE_N_ROT_AA:

case Type::FACE_ROT_NORMAL_PT:

break;

}

int position;

ObjectPicker canvas = {};

canvas.camera = camera;

canvas.point = p;

canvas.minDistance = 1e12;

Draw(DrawAs::DEFAULT, &canvas);

position = canvas.position;

canvas.Clear();

return position;

if(IsPoint()) return false;

if(IsWorkplane()) return false;

if(IsNormal()) return false;

return true;

Group *g = SK.GetGroup(group);

if(g->h == Group::HGROUP_REFERENCES && IsNormal()) {

// The reference normals are always shown

return true;

}

if(!(g->IsVisible())) return false;

if(IsPoint() && !SS.GW.showPoints) return false;

if(IsNormal() && !SS.GW.showNormals) return false;

if(construction && !SS.GW.showConstruction) return false;

if(!SS.GW.showWorkplanes) {

if(IsWorkplane() && !h.isFromRequest()) {

if(g->h != SS.GW.activeGroup) {

// The group-associated workplanes are hidden outside

// their group.

return false;

}

}

}

if(style.v) {

Style *s = Style::Get(style);

if(!s->visible) return false;

}

if(forceHidden) return false;

return true;

if(IsPoint()) actPoint = PointGetNum();

if(IsNormal()) actNormal = NormalGetNum();

if(type == Type::DISTANCE || type == Type::DISTANCE_N_COPY) {

actDistance = DistanceGetNum();

}

if(IsFace()) {

actPoint = FaceGetPointNum();

Vector n = FaceGetNormalNum();

actNormal = Quaternion::From(0, n.x, n.y, n.z);

}

if(forExport) {

// Visibility in copied linked entities follows source file

actVisible = IsVisible();

} else {

// Copied entities within a file are always visible

actVisible = true;

}

static const int MAX_N = BandedMatrix::MAX_UNKNOWNS;

int ep = extraPoints;

// The number of unknowns to solve for.

int n = periodic ? 3 + ep : ep;

ssassert(n < MAX_N, "Too many unknowns");

// The number of on-curve points, one more than the number of segments.

int pts = periodic ? 4 + ep : 2 + ep;

int i, j, a;

// The starting and finishing control points that define our end tangents

// (if the spline isn't periodic), and the on-curve points.

Vector ctrl_s = Vector::From(0, 0, 0);

Vector ctrl_f = Vector::From(0, 0, 0);

Vector pt[MAX_N+4];

if(periodic) {

for(i = 0; i < ep + 3; i++) {

pt[i] = SK.GetEntity(point[i])->PointGetNum();

}

pt[i++] = SK.GetEntity(point[0])->PointGetNum();

} else {

ctrl_s = SK.GetEntity(point[1])->PointGetNum();

ctrl_f = SK.GetEntity(point[ep+2])->PointGetNum();

j = 0;

pt[j++] = SK.GetEntity(point[0])->PointGetNum();

for(i = 2; i <= ep + 1; i++) {

pt[j++] = SK.GetEntity(point[i])->PointGetNum();

}

pt[j++] = SK.GetEntity(point[ep+3])->PointGetNum();

}

// The unknowns that we will be solving for, a set for each coordinate.

double Xx[MAX_N], Xy[MAX_N], Xz[MAX_N];

// For a cubic Bezier section f(t) as t goes from 0 to 1,

// f' (0) = 3*(P1 - P0)

// f' (1) = 3*(P3 - P2)

// f''(0) = 6*(P0 - 2*P1 + P2)

// f''(1) = 6*(P3 - 2*P2 + P1)

for(a = 0; a < 3; a++) {

BandedMatrix bm = {};

bm.n = n;

for(i = 0; i < n; i++) {

int im, it, ip;

if(periodic) {

im = WRAP(i - 1, n);

it = i;

ip = WRAP(i + 1, n);

} else {

im = i;

it = i + 1;

ip = i + 2;

}

// All of these are expressed in terms of a constant part, and

// of X[i-1], X[i], and X[i+1]; so let these be the four

// components of that vector;

Vector4 A, B, C, D, E;

// The on-curve interpolated point

C = Vector4::From((pt[it]).Element(a), 0, 0, 0);

// control point one back, C - X[i]

B = C.Plus(Vector4::From(0, 0, -1, 0));

// control point one forward, C + X[i]

D = C.Plus(Vector4::From(0, 0, 1, 0));

// control point two back

if(i == 0 && !periodic) {

A = Vector4::From(ctrl_s.Element(a), 0, 0, 0);

} else {

// pt[im] + X[i-1]

A = Vector4::From(pt[im].Element(a), 1, 0, 0);

}

// control point two forward

if(i == (n - 1) && !periodic) {

E = Vector4::From(ctrl_f.Element(a), 0, 0, 0);

} else {

// pt[ip] - X[i+1]

E = Vector4::From((pt[ip]).Element(a), 0, 0, -1);

}

// Write the second derivatives of each segment, dropping constant

Vector4 fprev_pp = (C.Minus(B.ScaledBy(2))).Plus(A),

fnext_pp = (C.Minus(D.ScaledBy(2))).Plus(E),

eq = fprev_pp.Minus(fnext_pp);

bm.B[i] = -eq.w;

if(periodic) {

bm.A[i][WRAP(i-2, n)] = eq.x;

bm.A[i][WRAP(i-1, n)] = eq.y;

bm.A[i][i] = eq.z;

} else {

// The wrapping would work, except when n = 1 and everything

// wraps to zero...

if(i > 0) bm.A[i][i - 1] = eq.x;

/**/ bm.A[i][i] = eq.y;

if(i < (n-1)) bm.A[i][i + 1] = eq.z;

}

}

bm.Solve();

double *X = (a == 0) ? Xx :

(a == 1) ? Xy :

Xz;

memcpy(X, bm.X, n*sizeof(double));

}

for(i = 0; i < pts - 1; i++) {

Vector p0, p1, p2, p3;

if(periodic) {

p0 = pt[i];

int iw = WRAP(i - 1, n);

p1 = p0.Plus(Vector::From(Xx[iw], Xy[iw], Xz[iw]));

} else if(i == 0) {

p0 = pt[0];

p1 = ctrl_s;

} else {

p0 = pt[i];

p1 = p0.Plus(Vector::From(Xx[i-1], Xy[i-1], Xz[i-1]));

}

if(periodic) {

p3 = pt[i+1];

int iw = WRAP(i, n);

p2 = p3.Minus(Vector::From(Xx[iw], Xy[iw], Xz[iw]));

} else if(i == (pts - 2)) {

p3 = pt[pts-1];

p2 = ctrl_f;

} else {

p3 = pt[i+1];

p2 = p3.Minus(Vector::From(Xx[i], Xy[i], Xz[i]));

}

SBezier sb = SBezier::From(p0, p1, p2, p3);

sbl->l.Add(&sb);

}

SBezier sb;

int i = sbl->l.n;

switch(type) {

case Type::LINE_SEGMENT: {

Vector a = SK.GetEntity(point[0])->PointGetNum();

Vector b = SK.GetEntity(point[1])->PointGetNum();

sb = SBezier::From(a, b);

sb.entity = h.v;

sbl->l.Add(&sb);

break;

}

case Type::CUBIC:

ComputeInterpolatingSpline(sbl, /*periodic=*/false);

break;

case Type::CUBIC_PERIODIC:

ComputeInterpolatingSpline(sbl, /*periodic=*/true);

break;

case Type::CIRCLE:

case Type::ARC_OF_CIRCLE: {

Vector center = SK.GetEntity(point[0])->PointGetNum();

Quaternion q = SK.GetEntity(normal)->NormalGetNum();

Vector u = q.RotationU(), v = q.RotationV();

double r = CircleGetRadiusNum();

double thetaa, thetab, dtheta;

if(r < LENGTH_EPS) {

// If a circle or an arc gets dragged through zero radius,

// then we just don't generate anything.

break;

}

if(type == Type::CIRCLE) {

thetaa = 0;

thetab = 2*PI;

dtheta = 2*PI;

} else {

ArcGetAngles(&thetaa, &thetab, &dtheta);

}

int i, n;

if(dtheta > (3*PI/2 + 0.01)) {

n = 4;

} else if(dtheta > (PI + 0.01)) {

n = 3;

} else if(dtheta > (PI/2 + 0.01)) {

n = 2;

} else {

n = 1;

}

dtheta /= n;

for(i = 0; i < n; i++) {

double s, c;

c = cos(thetaa);

s = sin(thetaa);

// The start point of the curve, and the tangent vector at

// that start point.

Vector p0 = center.Plus(u.ScaledBy( r*c)).Plus(v.ScaledBy(r*s)),

t0 = u.ScaledBy(-r*s). Plus(v.ScaledBy(r*c));

thetaa += dtheta;

c = cos(thetaa);

s = sin(thetaa);

Vector p2 = center.Plus(u.ScaledBy( r*c)).Plus(v.ScaledBy(r*s)),

t2 = u.ScaledBy(-r*s). Plus(v.ScaledBy(r*c));

// The control point must lie on both tangents.

Vector p1 = Vector::AtIntersectionOfLines(p0, p0.Plus(t0),

p2, p2.Plus(t2),

NULL);

SBezier sb = SBezier::From(p0, p1, p2);

sb.weight[1] = cos(dtheta/2);

sbl->l.Add(&sb);

}

break;

}

case Type::TTF_TEXT: {

Vector topLeft = SK.GetEntity(point[0])->PointGetNum();

Vector botLeft = SK.GetEntity(point[1])->PointGetNum();

Vector n = Normal()->NormalN();

Vector v = topLeft.Minus(botLeft);

Vector u = (v.Cross(n)).WithMagnitude(v.Magnitude());

SS.fonts.PlotString(font, str, sbl, botLeft, u, v);

break;

}

default:

// Not a problem, points and normals and such don't generate curves

break;

}

// Record our style for all of the Beziers that we just created.

for(; i < sbl->l.n; i++) {

sbl->l[i].auxA = style.v;

}

if(!(how == DrawAs::HOVERED || how == DrawAs::SELECTED) &&

!IsVisible()) return;

int zIndex;

if(IsPoint()) {

zIndex = 5;

} else if(how == DrawAs::HIDDEN) {

zIndex = 2;

} else if(group != SS.GW.activeGroup) {

zIndex = 3;

} else {

zIndex = 4;

}

hStyle hs;

if(IsPoint()) {

hs.v = Style::DATUM;

} else if(IsNormal() || type == Type::WORKPLANE) {

hs.v = Style::NORMALS;

} else {

hs = Style::ForEntity(h);

}

Canvas::Stroke stroke = Style::Stroke(hs);

switch(how) {

case DrawAs::DEFAULT:

stroke.layer = Canvas::Layer::NORMAL;

break;

case DrawAs::OVERLAY:

stroke.layer = Canvas::Layer::FRONT;

break;

case DrawAs::HIDDEN:

stroke.layer = Canvas::Layer::OCCLUDED;

stroke.stipplePattern = Style::PatternType({ Style::HIDDEN_EDGE });

stroke.stippleScale = Style::Get({ Style::HIDDEN_EDGE })->stippleScale;

break;

case DrawAs::HOVERED:

stroke.layer = Canvas::Layer::FRONT;

stroke.color = Style::Color(Style::HOVERED);

break;

case DrawAs::SELECTED:

stroke.layer = Canvas::Layer::FRONT;

stroke.color = Style::Color(Style::SELECTED);

break;

}

stroke.zIndex = zIndex;

Canvas::hStroke hcs = canvas->GetStroke(stroke);

switch(type) {

case Type::POINT_N_COPY:

case Type::POINT_N_TRANS:

case Type::POINT_N_ROT_TRANS:

case Type::POINT_N_ROT_AA:

case Type::POINT_N_ROT_AXIS_TRANS:

case Type::POINT_IN_3D:

case Type::POINT_IN_2D: {

if(how == DrawAs::HIDDEN) return;

// If we're analyzing the sketch to show the degrees of freedom,

// then we draw big colored squares over the points that are

// free to move.

bool free = false;

if(type == Type::POINT_IN_3D) {

Param *px = SK.GetParam(param[0]),

*py = SK.GetParam(param[1]),

*pz = SK.GetParam(param[2]);

free = px->free || py->free || pz->free;

} else if(type == Type::POINT_IN_2D) {

Param *pu = SK.GetParam(param[0]),

*pv = SK.GetParam(param[1]);

free = pu->free || pv->free;

}

Canvas::Stroke pointStroke = {};

pointStroke.layer = (free) ? Canvas::Layer::FRONT : stroke.layer;

pointStroke.zIndex = stroke.zIndex;

pointStroke.color = stroke.color;

pointStroke.width = 7.0;

pointStroke.unit = Canvas::Unit::PX;

Canvas::hStroke hcsPoint = canvas->GetStroke(pointStroke);

if(free) {

Canvas::Stroke analyzeStroke = Style::Stroke(Style::ANALYZE);

analyzeStroke.width = 14.0;

analyzeStroke.layer = Canvas::Layer::FRONT;

Canvas::hStroke hcsAnalyze = canvas->GetStroke(analyzeStroke);

canvas->DrawPoint(PointGetNum(), hcsAnalyze);

}

canvas->DrawPoint(PointGetNum(), hcsPoint);

return;

}

case Type::NORMAL_N_COPY:

case Type::NORMAL_N_ROT:

case Type::NORMAL_N_ROT_AA:

case Type::NORMAL_IN_3D:

case Type::NORMAL_IN_2D: {

const Camera &camera = canvas->GetCamera();

if(how == DrawAs::HIDDEN) return;

for(int i = 0; i < 2; i++) {

bool asReference = (i == 1);

if(asReference) {

if(!h.request().IsFromReferences()) continue;

} else {

if(!SK.GetGroup(group)->IsVisible() || !SS.GW.showNormals) continue;

}

stroke.layer = (asReference) ? Canvas::Layer::FRONT : Canvas::Layer::NORMAL;

if(how != DrawAs::HOVERED && how != DrawAs::SELECTED) {

// Always draw the x, y, and z axes in red, green, and blue;

// brighter for the ones at the bottom left of the screen,

// dimmer for the ones at the model origin.

hRequest hr = h.request();

uint8_t luma = (asReference) ? 255 : 100;

if(hr == Request::HREQUEST_REFERENCE_XY) {

stroke.color = RgbaColor::From(0, 0, luma);

} else if(hr == Request::HREQUEST_REFERENCE_YZ) {

stroke.color = RgbaColor::From(luma, 0, 0);

} else if(hr == Request::HREQUEST_REFERENCE_ZX) {

stroke.color = RgbaColor::From(0, luma, 0);

}

}

Quaternion q = NormalGetNum();

Vector tail;

if(asReference) {

// Draw an extra copy of the x, y, and z axes, that's

// always in the corner of the view and at the front.

// So those are always available, perhaps useful.

stroke.width = 2;

double s = camera.scale;

double h = 60 - camera.height / 2.0;

double w = 60 - camera.width / 2.0;

// Shift the axis to the right if they would overlap with the toolbar.

if(SS.showToolbar) {

if(h + 30 > -(34*16 + 3*16 + 8) / 2)

w += 60;

}

tail = camera.projRight.ScaledBy(w/s).Plus(

camera.projUp. ScaledBy(h/s)).Minus(camera.offset);

} else {

tail = SK.GetEntity(point[0])->PointGetNum();

}

tail = camera.AlignToPixelGrid(tail);

hcs = canvas->GetStroke(stroke);

Vector v = (q.RotationN()).WithMagnitude(50.0 / camera.scale);

Vector tip = tail.Plus(v);

canvas->DrawLine(tail, tip, hcs);

v = v.WithMagnitude(12.0 / camera.scale);

Vector axis = q.RotationV();

canvas->DrawLine(tip, tip.Minus(v.RotatedAbout(axis, 0.6)), hcs);

canvas->DrawLine(tip, tip.Minus(v.RotatedAbout(axis, -0.6)), hcs);

if(type == Type::NORMAL_IN_3D) {

Param *nw = SK.GetParam(param[0]),

*nx = SK.GetParam(param[1]),

*ny = SK.GetParam(param[2]),

*nz = SK.GetParam(param[3]);

if(nw->free || nx->free || ny->free || nz->free) {

Canvas::Stroke analyzeStroke = Style::Stroke(Style::ANALYZE);

analyzeStroke.layer = Canvas::Layer::FRONT;

Canvas::hStroke hcsAnalyze = canvas->GetStroke(analyzeStroke);

canvas->DrawLine(tail, tip, hcsAnalyze);

}

}

}

return;

}

case Type::DISTANCE:

case Type::DISTANCE_N_COPY:

// These are used only as data structures, nothing to display.

return;

case Type::WORKPLANE: {

const Camera &camera = canvas->GetCamera();

Vector p = SK.GetEntity(point[0])->PointGetNum();

p = camera.AlignToPixelGrid(p);

Vector u = Normal()->NormalU();

Vector v = Normal()->NormalV();

double s = (std::min(camera.width, camera.height)) * 0.45 / camera.scale;

Vector us = u.ScaledBy(s);

Vector vs = v.ScaledBy(s);

Vector pp = p.Plus (us).Plus (vs);

Vector pm = p.Plus (us).Minus(vs);

Vector mm = p.Minus(us).Minus(vs), mm2 = mm;

Vector mp = p.Minus(us).Plus (vs);

Canvas::Stroke strokeBorder = stroke;

strokeBorder.zIndex -= 3;

strokeBorder.stipplePattern = StipplePattern::SHORT_DASH;

strokeBorder.stippleScale = 8.0;

Canvas::hStroke hcsBorder = canvas->GetStroke(strokeBorder);

double textHeight = Style::TextHeight(hs) / camera.scale;

if(!h.isFromRequest()) {

mm = mm.Plus(v.ScaledBy(textHeight * 4.7));

mm2 = mm2.Plus(u.ScaledBy(textHeight * 4.7));

canvas->DrawLine(mm2, mm, hcsBorder);

}

canvas->DrawLine(pp, pm, hcsBorder);

canvas->DrawLine(mm2, pm, hcsBorder);

canvas->DrawLine(mm, mp, hcsBorder);

canvas->DrawLine(pp, mp, hcsBorder);

Vector o = mm2.Plus(u.ScaledBy(3.0 / camera.scale)).Plus(

v.ScaledBy(3.0 / camera.scale));

std::string shortDesc = DescriptionString().substr(5);

canvas->DrawVectorText(shortDesc, textHeight, o, u, v, hcs);

return;

}

case Type::LINE_SEGMENT:

case Type::CIRCLE:

case Type::ARC_OF_CIRCLE:

case Type::CUBIC:

case Type::CUBIC_PERIODIC:

case Type::TTF_TEXT: {

// Generate the rational polynomial curves, then piecewise linearize

// them, and display those.

if(!canvas->DrawBeziers(*GetOrGenerateBezierCurves(), hcs)) {

canvas->DrawEdges(*GetOrGenerateEdges(), hcs);

}

if(type == Type::CIRCLE) {

Entity *dist = SK.GetEntity(distance);

if(dist->type == Type::DISTANCE) {

Param *p = SK.GetParam(dist->param[0]);

if(p->free) {

Canvas::Stroke analyzeStroke = Style::Stroke(Style::ANALYZE);

analyzeStroke.layer = Canvas::Layer::FRONT;

Canvas::hStroke hcsAnalyze = canvas->GetStroke(analyzeStroke);

if(!canvas->DrawBeziers(*GetOrGenerateBezierCurves(), hcsAnalyze)) {

canvas->DrawEdges(*GetOrGenerateEdges(), hcsAnalyze);

}

}

}

}

return;

}

case Type::IMAGE: {

Canvas::Fill fill = {};

std::shared_ptr<Pixmap> pixmap;

switch(how) {

case DrawAs::HIDDEN: return;

case DrawAs::HOVERED: {

fill.color = Style::Color(Style::HOVERED).WithAlpha(180);

fill.pattern = Canvas::FillPattern::CHECKERED_A;

fill.zIndex = 2;

break;

}

case DrawAs::SELECTED: {

fill.color = Style::Color(Style::SELECTED).WithAlpha(180);

fill.pattern = Canvas::FillPattern::CHECKERED_B;

fill.zIndex = 1;

break;

}

default:

fill.color = RgbaColor::FromFloat(1.0f, 1.0f, 1.0f);

pixmap = SS.images[file];

break;

}

Canvas::hFill hf = canvas->GetFill(fill);

Vector v[4] = {};

for(int i = 0; i < 4; i++) {

v[i] = SK.GetEntity(point[i])->PointGetNum();

}

Vector iu = v[3].Minus(v[0]);

Vector iv = v[1].Minus(v[0]);

if(how == DrawAs::DEFAULT && pixmap == NULL) {

Canvas::Stroke stroke = Style::Stroke(Style::DRAW_ERROR);

stroke.color = stroke.color.WithAlpha(50);

Canvas::hStroke hs = canvas->GetStroke(stroke);

canvas->DrawLine(v[0], v[2], hs);

canvas->DrawLine(v[1], v[3], hs);

for(int i = 0; i < 4; i++) {

canvas->DrawLine(v[i], v[(i + 1) % 4], hs);

}

} else {

canvas->DrawPixmap(pixmap, v[0], iu, iv,

Point2d::From(0.0, 0.0), Point2d::From(1.0, 1.0), hf);

}

}

case Type::FACE_NORMAL_PT:

case Type::FACE_XPROD:

case Type::FACE_N_ROT_TRANS:

case Type::FACE_N_TRANS:

case Type::FACE_N_ROT_AA:

case Type::FACE_ROT_NORMAL_PT:

// Do nothing; these are drawn with the triangle mesh

return;

}

ssassert(false, "Unexpected entity type");