diff options
| -rw-r--r-- | lay/strain/solve.go | 150 |
1 files changed, 80 insertions, 70 deletions
diff --git a/lay/strain/solve.go b/lay/strain/solve.go index 41cabc5..5782f93 100644 --- a/lay/strain/solve.go +++ b/lay/strain/solve.go @@ -20,6 +20,15 @@ const ( fieldPriority = casso.Medium ) +// solver wraps Solver and protects the not-thread-safe casso.Solver. +type solver struct { + s *Solver + cs *casso.Solver + style *style.Style + fieldSizeConstrs []sizeConstraintSymbols + ctx context.Context +} + // Solver uses the Cassowary algorithm to partition a rectangle among // several layout fields. // @@ -39,8 +48,6 @@ type Solver struct { solveReqs chan solveRequest } -type fieldIndex int - // sizeConstraintSymbols is a set of constraint ID symbols that // control the upper/lower/exact bounds on the width and height of a // field. @@ -54,6 +61,8 @@ type sizeConstraintSymbols struct { // Nil means no constraint. } +type fieldIndex int + type constrainRequest struct { casso.Priority casso.Op @@ -98,98 +107,87 @@ func NewSolver(styl *style.Style, constraints []<-chan Constraint) (*Solver, err cancel() // destroy the solver }() - solver := casso.NewSolver() + cs := casso.NewSolver() container := NewSymRect() - if err := editRect(solver, container, casso.Strong); err != nil { + if err := editRect(cs, container, casso.Strong); err != nil { cancel() return nil, fmt.Errorf("error marking container symbol as editable: %w", err) } - s := &Solver{ - container, - fields, - fieldConstrs, - make(chan constrainRequest), - make(chan solveRequest), + s := &solver{ + &Solver{ + container, + fields, + fieldConstrs, + make(chan constrainRequest), + make(chan solveRequest), + }, + cs, + styl, + make([]sizeConstraintSymbols, nfields), + ctx, } - go s.run(ctx, solver, styl) - if err := s.addDefaultConstraints(); err != nil { + go s.run() + if err := s.s.addDefaultConstraints(); err != nil { cancel() return nil, fmt.Errorf("error adding default constraint: %w", err) } - return s, nil + return s.s, nil } -func (s *Solver) run(ctx context.Context, solver *casso.Solver, styl *style.Style) { - defer close(s.fieldConstrs) - defer close(s.layoutConstrs) - defer close(s.solveReqs) +func (s *solver) run() { + defer close(s.s.fieldConstrs) + defer close(s.s.layoutConstrs) + defer close(s.s.solveReqs) - fieldSizeConstrs := make([]sizeConstraintSymbols, len(s.fields)) for { select { - case tc, ok := <-s.fieldConstrs: - if !ok { - return - } + case tc := <-s.s.fieldConstrs: constr, i := tc.Val, tc.Tag - err := addFieldSizeConstraint(solver, styl, constr, s.fields[i], &fieldSizeConstrs[i]) - if err != nil { + if err := s.addFieldSizeConstraint(constr, s.s.fields[i], &s.fieldSizeConstrs[i]); err != nil { log.Err.Printf("error adding layout constraint %#v from field %d: %v\n", constr, i, err) } - case req := <-s.layoutConstrs: - _, err := addConstraint(solver, req.Priority, req.Op, req.constant, req.terms...) + case req := <-s.s.layoutConstrs: + _, err := s.addConstraint(req.Priority, req.Op, req.constant, req.terms...) req.res <- err - case req := <-s.solveReqs: - fields, err := s.solve(solver, req.container) + case req := <-s.s.solveReqs: + fields, err := s.solve(req.container) req.res <- solveResponse{fields, err} - case <-ctx.Done(): + case <-s.ctx.Done(): return } } } -func (s *Solver) addDefaultConstraints() error { - for _, field := range s.fields { - if err := s.addConstraintPt(solverPriority, casso.GTE, field.Origin, s.container.Origin); err != nil { - return err - } - if err := s.addConstraintPt(solverPriority, casso.LTE, field.Size, s.container.Size); err != nil { - return err - } - } - return nil -} - // addFieldSizeConstraint adds or modifies a constraint on the size of // a field, removing mutually exclusive constraints. -func addFieldSizeConstraint(s *casso.Solver, styl *style.Style, constr Constraint, field SymRect, fieldConstrs *sizeConstraintSymbols) error { +func (s *solver) addFieldSizeConstraint(constr Constraint, field SymRect, fieldConstrs *sizeConstraintSymbols) error { // Clear mutually exclusive constraints and replace with new one switch constr.Dimension { case Width: - width := float64(styl.Pixels(constr.Value).Round()) + width := float64(s.style.Pixels(constr.Value).Round()) switch constr.Op { case casso.EQ: - removeConstraints(s, fieldConstrs.widthEq, fieldConstrs.widthGte, fieldConstrs.widthLte) - c, err := addConstraint(s, fieldPriority, constr.Op, -width, field.Size.X.T(1.0)) + s.removeConstraints(fieldConstrs.widthEq, fieldConstrs.widthGte, fieldConstrs.widthLte) + c, err := s.addConstraint(fieldPriority, constr.Op, -width, field.Size.X.T(1.0)) if err != nil { return err } fieldConstrs.widthEq = &c case casso.GTE: - removeConstraints(s, fieldConstrs.widthEq, fieldConstrs.widthGte) - c, err := addConstraint(s, fieldPriority, constr.Op, -width, field.Size.X.T(1.0)) + s.removeConstraints(fieldConstrs.widthEq, fieldConstrs.widthGte) + c, err := s.addConstraint(fieldPriority, constr.Op, -width, field.Size.X.T(1.0)) if err != nil { return err } fieldConstrs.widthGte = &c case casso.LTE: - removeConstraints(s, fieldConstrs.widthEq, fieldConstrs.widthLte) - c, err := addConstraint(s, fieldPriority, constr.Op, -width, field.Size.X.T(1.0)) + s.removeConstraints(fieldConstrs.widthEq, fieldConstrs.widthLte) + c, err := s.addConstraint(fieldPriority, constr.Op, -width, field.Size.X.T(1.0)) if err != nil { return err } @@ -198,25 +196,25 @@ func addFieldSizeConstraint(s *casso.Solver, styl *style.Style, constr Constrain panic(fmt.Sprintf("unreachable: impossible %T: %v", constr.Op, constr.Op)) } case Height: - height := float64(styl.Pixels(constr.Value).Round()) + height := float64(s.style.Pixels(constr.Value).Round()) switch constr.Op { case casso.EQ: - removeConstraints(s, fieldConstrs.heightEq, fieldConstrs.heightGte, fieldConstrs.heightLte) - c, err := addConstraint(s, fieldPriority, constr.Op, -height, field.Size.Y.T(1.0)) + s.removeConstraints(fieldConstrs.heightEq, fieldConstrs.heightGte, fieldConstrs.heightLte) + c, err := s.addConstraint(fieldPriority, constr.Op, -height, field.Size.Y.T(1.0)) if err != nil { return err } fieldConstrs.heightEq = &c case casso.GTE: - removeConstraints(s, fieldConstrs.heightEq, fieldConstrs.heightGte) - c, err := addConstraint(s, fieldPriority, constr.Op, -height, field.Size.Y.T(1.0)) + s.removeConstraints(fieldConstrs.heightEq, fieldConstrs.heightGte) + c, err := s.addConstraint(fieldPriority, constr.Op, -height, field.Size.Y.T(1.0)) if err != nil { return err } fieldConstrs.heightGte = &c case casso.LTE: - removeConstraints(s, fieldConstrs.heightEq, fieldConstrs.heightLte) - c, err := addConstraint(s, fieldPriority, constr.Op, -height, field.Size.Y.T(1.0)) + s.removeConstraints(fieldConstrs.heightEq, fieldConstrs.heightLte) + c, err := s.addConstraint(fieldPriority, constr.Op, -height, field.Size.Y.T(1.0)) if err != nil { return err } @@ -231,10 +229,10 @@ func addFieldSizeConstraint(s *casso.Solver, styl *style.Style, constr Constrain return nil } -func removeConstraints(s *casso.Solver, constrs ...*casso.Symbol) error { +func (s *solver) removeConstraints(constrs ...*casso.Symbol) error { for _, constr := range constrs { if constr != nil { - if err := s.RemoveConstraint(*constr); err != nil { + if err := s.cs.RemoveConstraint(*constr); err != nil { return err } } @@ -242,30 +240,42 @@ func removeConstraints(s *casso.Solver, constrs ...*casso.Symbol) error { return nil } -func addConstraint(s *casso.Solver, priority casso.Priority, op casso.Op, constant float64, terms ...casso.Term) (casso.Symbol, error) { - return s.AddConstraintWithPriority(priority, casso.NewConstraint(op, constant, terms...)) +func (s *solver) addConstraint(priority casso.Priority, op casso.Op, constant float64, terms ...casso.Term) (casso.Symbol, error) { + return s.cs.AddConstraintWithPriority(priority, casso.NewConstraint(op, constant, terms...)) } -func (s *Solver) solve(solver *casso.Solver, container image.Rectangle) (fields []image.Rectangle, err error) { - if err := suggestRect(solver, s.container, container); err != nil { +func (s *solver) solve(container image.Rectangle) (fields []image.Rectangle, err error) { + if err := suggestRect(s.cs, s.s.container, container); err != nil { return nil, err } - fields = make([]image.Rectangle, len(s.fields)) - for i, field := range s.fields { + fields = make([]image.Rectangle, len(s.s.fields)) + for i, field := range s.s.fields { min := image.Pt( - s.val(solver, field.Origin.X), - s.val(solver, field.Origin.Y)) + s.val(field.Origin.X), + s.val(field.Origin.Y)) max := min.Add(image.Pt( - s.val(solver, field.Size.X), - s.val(solver, field.Size.Y))) + s.val(field.Size.X), + s.val(field.Size.Y))) fields[i] = image.Rectangle{min, max} } return fields, nil } -func (s *Solver) val(solver *casso.Solver, sym casso.Symbol) int { - return int(math.Round(solver.Val(sym))) +func (s *solver) val(sym casso.Symbol) int { + return int(math.Round(s.cs.Val(sym))) +} + +func (s *Solver) addDefaultConstraints() error { + for _, field := range s.fields { + if err := s.addConstraintPt(solverPriority, casso.GTE, field.Origin, s.container.Origin); err != nil { + return err + } + if err := s.addConstraintPt(solverPriority, casso.LTE, field.Size, s.container.Size); err != nil { + return err + } + } + return nil } // Container returns the Cassowary symbols representing the layout |