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Diffstat (limited to 'src/pkg/image/geom.go')
| -rw-r--r-- | src/pkg/image/geom.go | 234 |
1 files changed, 0 insertions, 234 deletions
diff --git a/src/pkg/image/geom.go b/src/pkg/image/geom.go deleted file mode 100644 index 6ebaf67da..000000000 --- a/src/pkg/image/geom.go +++ /dev/null @@ -1,234 +0,0 @@ -// Copyright 2010 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -package image - -import ( - "strconv" -) - -// A Point is an X, Y coordinate pair. The axes increase right and down. -type Point struct { - X, Y int -} - -// String returns a string representation of p like "(3,4)". -func (p Point) String() string { - return "(" + strconv.Itoa(p.X) + "," + strconv.Itoa(p.Y) + ")" -} - -// Add returns the vector p+q. -func (p Point) Add(q Point) Point { - return Point{p.X + q.X, p.Y + q.Y} -} - -// Sub returns the vector p-q. -func (p Point) Sub(q Point) Point { - return Point{p.X - q.X, p.Y - q.Y} -} - -// Mul returns the vector p*k. -func (p Point) Mul(k int) Point { - return Point{p.X * k, p.Y * k} -} - -// Div returns the vector p/k. -func (p Point) Div(k int) Point { - return Point{p.X / k, p.Y / k} -} - -// In reports whether p is in r. -func (p Point) In(r Rectangle) bool { - return r.Min.X <= p.X && p.X < r.Max.X && - r.Min.Y <= p.Y && p.Y < r.Max.Y -} - -// Mod returns the point q in r such that p.X-q.X is a multiple of r's width -// and p.Y-q.Y is a multiple of r's height. -func (p Point) Mod(r Rectangle) Point { - w, h := r.Dx(), r.Dy() - p = p.Sub(r.Min) - p.X = p.X % w - if p.X < 0 { - p.X += w - } - p.Y = p.Y % h - if p.Y < 0 { - p.Y += h - } - return p.Add(r.Min) -} - -// Eq reports whether p and q are equal. -func (p Point) Eq(q Point) bool { - return p.X == q.X && p.Y == q.Y -} - -// ZP is the zero Point. -var ZP Point - -// Pt is shorthand for Point{X, Y}. -func Pt(X, Y int) Point { - return Point{X, Y} -} - -// A Rectangle contains the points with Min.X <= X < Max.X, Min.Y <= Y < Max.Y. -// It is well-formed if Min.X <= Max.X and likewise for Y. Points are always -// well-formed. A rectangle's methods always return well-formed outputs for -// well-formed inputs. -type Rectangle struct { - Min, Max Point -} - -// String returns a string representation of r like "(3,4)-(6,5)". -func (r Rectangle) String() string { - return r.Min.String() + "-" + r.Max.String() -} - -// Dx returns r's width. -func (r Rectangle) Dx() int { - return r.Max.X - r.Min.X -} - -// Dy returns r's height. -func (r Rectangle) Dy() int { - return r.Max.Y - r.Min.Y -} - -// Size returns r's width and height. -func (r Rectangle) Size() Point { - return Point{ - r.Max.X - r.Min.X, - r.Max.Y - r.Min.Y, - } -} - -// Add returns the rectangle r translated by p. -func (r Rectangle) Add(p Point) Rectangle { - return Rectangle{ - Point{r.Min.X + p.X, r.Min.Y + p.Y}, - Point{r.Max.X + p.X, r.Max.Y + p.Y}, - } -} - -// Sub returns the rectangle r translated by -p. -func (r Rectangle) Sub(p Point) Rectangle { - return Rectangle{ - Point{r.Min.X - p.X, r.Min.Y - p.Y}, - Point{r.Max.X - p.X, r.Max.Y - p.Y}, - } -} - -// Inset returns the rectangle r inset by n, which may be negative. If either -// of r's dimensions is less than 2*n then an empty rectangle near the center -// of r will be returned. -func (r Rectangle) Inset(n int) Rectangle { - if r.Dx() < 2*n { - r.Min.X = (r.Min.X + r.Max.X) / 2 - r.Max.X = r.Min.X - } else { - r.Min.X += n - r.Max.X -= n - } - if r.Dy() < 2*n { - r.Min.Y = (r.Min.Y + r.Max.Y) / 2 - r.Max.Y = r.Min.Y - } else { - r.Min.Y += n - r.Max.Y -= n - } - return r -} - -// Intersect returns the largest rectangle contained by both r and s. If the -// two rectangles do not overlap then the zero rectangle will be returned. -func (r Rectangle) Intersect(s Rectangle) Rectangle { - if r.Min.X < s.Min.X { - r.Min.X = s.Min.X - } - if r.Min.Y < s.Min.Y { - r.Min.Y = s.Min.Y - } - if r.Max.X > s.Max.X { - r.Max.X = s.Max.X - } - if r.Max.Y > s.Max.Y { - r.Max.Y = s.Max.Y - } - if r.Min.X > r.Max.X || r.Min.Y > r.Max.Y { - return ZR - } - return r -} - -// Union returns the smallest rectangle that contains both r and s. -func (r Rectangle) Union(s Rectangle) Rectangle { - if r.Min.X > s.Min.X { - r.Min.X = s.Min.X - } - if r.Min.Y > s.Min.Y { - r.Min.Y = s.Min.Y - } - if r.Max.X < s.Max.X { - r.Max.X = s.Max.X - } - if r.Max.Y < s.Max.Y { - r.Max.Y = s.Max.Y - } - return r -} - -// Empty reports whether the rectangle contains no points. -func (r Rectangle) Empty() bool { - return r.Min.X >= r.Max.X || r.Min.Y >= r.Max.Y -} - -// Eq reports whether r and s are equal. -func (r Rectangle) Eq(s Rectangle) bool { - return r.Min.X == s.Min.X && r.Min.Y == s.Min.Y && - r.Max.X == s.Max.X && r.Max.Y == s.Max.Y -} - -// Overlaps reports whether r and s have a non-empty intersection. -func (r Rectangle) Overlaps(s Rectangle) bool { - return r.Min.X < s.Max.X && s.Min.X < r.Max.X && - r.Min.Y < s.Max.Y && s.Min.Y < r.Max.Y -} - -// In reports whether every point in r is in s. -func (r Rectangle) In(s Rectangle) bool { - if r.Empty() { - return true - } - // Note that r.Max is an exclusive bound for r, so that r.In(s) - // does not require that r.Max.In(s). - return s.Min.X <= r.Min.X && r.Max.X <= s.Max.X && - s.Min.Y <= r.Min.Y && r.Max.Y <= s.Max.Y -} - -// Canon returns the canonical version of r. The returned rectangle has minimum -// and maximum coordinates swapped if necessary so that it is well-formed. -func (r Rectangle) Canon() Rectangle { - if r.Max.X < r.Min.X { - r.Min.X, r.Max.X = r.Max.X, r.Min.X - } - if r.Max.Y < r.Min.Y { - r.Min.Y, r.Max.Y = r.Max.Y, r.Min.Y - } - return r -} - -// ZR is the zero Rectangle. -var ZR Rectangle - -// Rect is shorthand for Rectangle{Pt(x0, y0), Pt(x1, y1)}. -func Rect(x0, y0, x1, y1 int) Rectangle { - if x0 > x1 { - x0, x1 = x1, x0 - } - if y0 > y1 { - y0, y1 = y1, y0 - } - return Rectangle{Point{x0, y0}, Point{x1, y1}} -} |