From e1e8d058a33f7566f9c565d04b0d8b56f9645c35 Mon Sep 17 00:00:00 2001 From: Dimitri Sokolyuk Date: Wed, 25 Apr 2018 09:28:54 +0200 Subject: add vendor --- vendor/golang.org/x/image/math/fixed/fixed.go | 410 ++++++++++++++++++++++++++ 1 file changed, 410 insertions(+) create mode 100644 vendor/golang.org/x/image/math/fixed/fixed.go (limited to 'vendor/golang.org/x/image/math/fixed') diff --git a/vendor/golang.org/x/image/math/fixed/fixed.go b/vendor/golang.org/x/image/math/fixed/fixed.go new file mode 100644 index 0000000..3d91663 --- /dev/null +++ b/vendor/golang.org/x/image/math/fixed/fixed.go @@ -0,0 +1,410 @@ +// Copyright 2015 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 fixed implements fixed-point integer types. +package fixed // import "golang.org/x/image/math/fixed" + +import ( + "fmt" +) + +// TODO: implement fmt.Formatter for %f and %g. + +// I returns the integer value i as an Int26_6. +// +// For example, passing the integer value 2 yields Int26_6(128). +func I(i int) Int26_6 { + return Int26_6(i << 6) +} + +// Int26_6 is a signed 26.6 fixed-point number. +// +// The integer part ranges from -33554432 to 33554431, inclusive. The +// fractional part has 6 bits of precision. +// +// For example, the number one-and-a-quarter is Int26_6(1<<6 + 1<<4). +type Int26_6 int32 + +// String returns a human-readable representation of a 26.6 fixed-point number. +// +// For example, the number one-and-a-quarter becomes "1:16". +func (x Int26_6) String() string { + const shift, mask = 6, 1<<6 - 1 + if x >= 0 { + return fmt.Sprintf("%d:%02d", int32(x>>shift), int32(x&mask)) + } + x = -x + if x >= 0 { + return fmt.Sprintf("-%d:%02d", int32(x>>shift), int32(x&mask)) + } + return "-33554432:00" // The minimum value is -(1<<25). +} + +// Floor returns the greatest integer value less than or equal to x. +// +// Its return type is int, not Int26_6. +func (x Int26_6) Floor() int { return int((x + 0x00) >> 6) } + +// Round returns the nearest integer value to x. Ties are rounded up. +// +// Its return type is int, not Int26_6. +func (x Int26_6) Round() int { return int((x + 0x20) >> 6) } + +// Ceil returns the least integer value greater than or equal to x. +// +// Its return type is int, not Int26_6. +func (x Int26_6) Ceil() int { return int((x + 0x3f) >> 6) } + +// Mul returns x*y in 26.6 fixed-point arithmetic. +func (x Int26_6) Mul(y Int26_6) Int26_6 { + return Int26_6((int64(x)*int64(y) + 1<<5) >> 6) +} + +// Int52_12 is a signed 52.12 fixed-point number. +// +// The integer part ranges from -2251799813685248 to 2251799813685247, +// inclusive. The fractional part has 12 bits of precision. +// +// For example, the number one-and-a-quarter is Int52_12(1<<12 + 1<<10). +type Int52_12 int64 + +// String returns a human-readable representation of a 52.12 fixed-point +// number. +// +// For example, the number one-and-a-quarter becomes "1:1024". +func (x Int52_12) String() string { + const shift, mask = 12, 1<<12 - 1 + if x >= 0 { + return fmt.Sprintf("%d:%04d", int64(x>>shift), int64(x&mask)) + } + x = -x + if x >= 0 { + return fmt.Sprintf("-%d:%04d", int64(x>>shift), int64(x&mask)) + } + return "-2251799813685248:0000" // The minimum value is -(1<<51). +} + +// Floor returns the greatest integer value less than or equal to x. +// +// Its return type is int, not Int52_12. +func (x Int52_12) Floor() int { return int((x + 0x000) >> 12) } + +// Round returns the nearest integer value to x. Ties are rounded up. +// +// Its return type is int, not Int52_12. +func (x Int52_12) Round() int { return int((x + 0x800) >> 12) } + +// Ceil returns the least integer value greater than or equal to x. +// +// Its return type is int, not Int52_12. +func (x Int52_12) Ceil() int { return int((x + 0xfff) >> 12) } + +// Mul returns x*y in 52.12 fixed-point arithmetic. +func (x Int52_12) Mul(y Int52_12) Int52_12 { + const M, N = 52, 12 + lo, hi := muli64(int64(x), int64(y)) + ret := Int52_12(hi<>N) + ret += Int52_12((lo >> (N - 1)) & 1) // Round to nearest, instead of rounding down. + return ret +} + +// muli64 multiplies two int64 values, returning the 128-bit signed integer +// result as two uint64 values. +// +// This implementation is similar to $GOROOT/src/runtime/softfloat64.go's mullu +// function, which is in turn adapted from Hacker's Delight. +func muli64(u, v int64) (lo, hi uint64) { + const ( + s = 32 + mask = 1<> s) + u0 := uint64(u & mask) + v1 := uint64(v >> s) + v0 := uint64(v & mask) + + w0 := u0 * v0 + t := u1*v0 + w0>>s + w1 := t & mask + w2 := uint64(int64(t) >> s) + w1 += u0 * v1 + return uint64(u) * uint64(v), u1*v1 + w2 + uint64(int64(w1)>>s) +} + +// P returns the integer values x and y as a Point26_6. +// +// For example, passing the integer values (2, -3) yields Point26_6{128, -192}. +func P(x, y int) Point26_6 { + return Point26_6{Int26_6(x << 6), Int26_6(y << 6)} +} + +// Point26_6 is a 26.6 fixed-point coordinate pair. +// +// It is analogous to the image.Point type in the standard library. +type Point26_6 struct { + X, Y Int26_6 +} + +// Add returns the vector p+q. +func (p Point26_6) Add(q Point26_6) Point26_6 { + return Point26_6{p.X + q.X, p.Y + q.Y} +} + +// Sub returns the vector p-q. +func (p Point26_6) Sub(q Point26_6) Point26_6 { + return Point26_6{p.X - q.X, p.Y - q.Y} +} + +// Mul returns the vector p*k. +func (p Point26_6) Mul(k Int26_6) Point26_6 { + return Point26_6{p.X * k / 64, p.Y * k / 64} +} + +// Div returns the vector p/k. +func (p Point26_6) Div(k Int26_6) Point26_6 { + return Point26_6{p.X * 64 / k, p.Y * 64 / k} +} + +// In returns whether p is in r. +func (p Point26_6) In(r Rectangle26_6) bool { + return r.Min.X <= p.X && p.X < r.Max.X && r.Min.Y <= p.Y && p.Y < r.Max.Y +} + +// Point52_12 is a 52.12 fixed-point coordinate pair. +// +// It is analogous to the image.Point type in the standard library. +type Point52_12 struct { + X, Y Int52_12 +} + +// Add returns the vector p+q. +func (p Point52_12) Add(q Point52_12) Point52_12 { + return Point52_12{p.X + q.X, p.Y + q.Y} +} + +// Sub returns the vector p-q. +func (p Point52_12) Sub(q Point52_12) Point52_12 { + return Point52_12{p.X - q.X, p.Y - q.Y} +} + +// Mul returns the vector p*k. +func (p Point52_12) Mul(k Int52_12) Point52_12 { + return Point52_12{p.X * k / 4096, p.Y * k / 4096} +} + +// Div returns the vector p/k. +func (p Point52_12) Div(k Int52_12) Point52_12 { + return Point52_12{p.X * 4096 / k, p.Y * 4096 / k} +} + +// In returns whether p is in r. +func (p Point52_12) In(r Rectangle52_12) bool { + return r.Min.X <= p.X && p.X < r.Max.X && r.Min.Y <= p.Y && p.Y < r.Max.Y +} + +// R returns the integer values minX, minY, maxX, maxY as a Rectangle26_6. +// +// For example, passing the integer values (0, 1, 2, 3) yields +// Rectangle26_6{Point26_6{0, 64}, Point26_6{128, 192}}. +// +// Like the image.Rect function in the standard library, the returned rectangle +// has minimum and maximum coordinates swapped if necessary so that it is +// well-formed. +func R(minX, minY, maxX, maxY int) Rectangle26_6 { + if minX > maxX { + minX, maxX = maxX, minX + } + if minY > maxY { + minY, maxY = maxY, minY + } + return Rectangle26_6{ + Point26_6{ + Int26_6(minX << 6), + Int26_6(minY << 6), + }, + Point26_6{ + Int26_6(maxX << 6), + Int26_6(maxY << 6), + }, + } +} + +// Rectangle26_6 is a 26.6 fixed-point coordinate rectangle. The Min bound is +// inclusive and the Max bound is exclusive. It is well-formed if Min.X <= +// Max.X and likewise for Y. +// +// It is analogous to the image.Rectangle type in the standard library. +type Rectangle26_6 struct { + Min, Max Point26_6 +} + +// Add returns the rectangle r translated by p. +func (r Rectangle26_6) Add(p Point26_6) Rectangle26_6 { + return Rectangle26_6{ + Point26_6{r.Min.X + p.X, r.Min.Y + p.Y}, + Point26_6{r.Max.X + p.X, r.Max.Y + p.Y}, + } +} + +// Sub returns the rectangle r translated by -p. +func (r Rectangle26_6) Sub(p Point26_6) Rectangle26_6 { + return Rectangle26_6{ + Point26_6{r.Min.X - p.X, r.Min.Y - p.Y}, + Point26_6{r.Max.X - p.X, r.Max.Y - p.Y}, + } +} + +// 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 Rectangle26_6) Intersect(s Rectangle26_6) Rectangle26_6 { + 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 + } + // Letting r0 and s0 be the values of r and s at the time that the method + // is called, this next line is equivalent to: + // + // if max(r0.Min.X, s0.Min.X) >= min(r0.Max.X, s0.Max.X) || likewiseForY { etc } + if r.Empty() { + return Rectangle26_6{} + } + return r +} + +// Union returns the smallest rectangle that contains both r and s. +func (r Rectangle26_6) Union(s Rectangle26_6) Rectangle26_6 { + if r.Empty() { + return s + } + if s.Empty() { + return r + } + 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 returns whether the rectangle contains no points. +func (r Rectangle26_6) Empty() bool { + return r.Min.X >= r.Max.X || r.Min.Y >= r.Max.Y +} + +// In returns whether every point in r is in s. +func (r Rectangle26_6) In(s Rectangle26_6) 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 +} + +// Rectangle52_12 is a 52.12 fixed-point coordinate rectangle. The Min bound is +// inclusive and the Max bound is exclusive. It is well-formed if Min.X <= +// Max.X and likewise for Y. +// +// It is analogous to the image.Rectangle type in the standard library. +type Rectangle52_12 struct { + Min, Max Point52_12 +} + +// Add returns the rectangle r translated by p. +func (r Rectangle52_12) Add(p Point52_12) Rectangle52_12 { + return Rectangle52_12{ + Point52_12{r.Min.X + p.X, r.Min.Y + p.Y}, + Point52_12{r.Max.X + p.X, r.Max.Y + p.Y}, + } +} + +// Sub returns the rectangle r translated by -p. +func (r Rectangle52_12) Sub(p Point52_12) Rectangle52_12 { + return Rectangle52_12{ + Point52_12{r.Min.X - p.X, r.Min.Y - p.Y}, + Point52_12{r.Max.X - p.X, r.Max.Y - p.Y}, + } +} + +// 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 Rectangle52_12) Intersect(s Rectangle52_12) Rectangle52_12 { + 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 + } + // Letting r0 and s0 be the values of r and s at the time that the method + // is called, this next line is equivalent to: + // + // if max(r0.Min.X, s0.Min.X) >= min(r0.Max.X, s0.Max.X) || likewiseForY { etc } + if r.Empty() { + return Rectangle52_12{} + } + return r +} + +// Union returns the smallest rectangle that contains both r and s. +func (r Rectangle52_12) Union(s Rectangle52_12) Rectangle52_12 { + if r.Empty() { + return s + } + if s.Empty() { + return r + } + 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 returns whether the rectangle contains no points. +func (r Rectangle52_12) Empty() bool { + return r.Min.X >= r.Max.X || r.Min.Y >= r.Max.Y +} + +// In returns whether every point in r is in s. +func (r Rectangle52_12) In(s Rectangle52_12) 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 +} -- cgit v1.2.3