ee31300452
benchmark old ns/op new ns/op delta BenchmarkSin 98156 32725 -66.66% LGTM=crawshaw, minux R=crawshaw, minux CC=golang-codereviews https://golang.org/cl/156590043
60 lines
1.5 KiB
Go
60 lines
1.5 KiB
Go
// Copyright 2014 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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//go:generate go run gen.go -output table.go
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// Package f32 implements some linear algebra and GL helpers for float32s.
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//
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// Types defined in this package have methods implementing common
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// mathematical operations. The common form for these functions is
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//
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// func (dst *T) Op(lhs, rhs *T)
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//
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// which reads in traditional mathematical notation as
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//
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// dst = lhs op rhs.
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//
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// It is safe to use the destination address as the left-hand side,
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// that is, dst *= rhs is dst.Mul(dst, rhs).
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//
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// WARNING
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//
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// The interface to this package is not stable. It will change considerably.
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// Only use functions that provide package documentation. Semantics are
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// non-obvious. Be prepared for the package name to change.
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package f32
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import "math"
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type Radian float32
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func Cos(x float32) float32 {
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const n = sinTableLen
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i := uint32(int32(x * (n / math.Pi)))
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i += n / 2
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i &= 2*n - 1
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if i >= n {
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return -sinTable[i&(n-1)]
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}
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return sinTable[i&(n-1)]
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}
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func Sin(x float32) float32 {
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const n = sinTableLen
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i := uint32(int32(x * (n / math.Pi)))
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i &= 2*n - 1
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if i >= n {
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return -sinTable[i&(n-1)]
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}
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return sinTable[i&(n-1)]
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}
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func Sqrt(x float32) float32 {
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return float32(math.Sqrt(float64(x))) // TODO(crawshaw): implement
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}
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func Tan(x float32) float32 {
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return float32(math.Tan(float64(x))) // TODO(crawshaw): fast version
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}
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