github.com/coming-chat/gomobile@v0.0.0-20220601074111-56995f7d7aba/exp/f32/vec4.go (about)

     1  // Copyright 2014 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package f32
     6  
     7  import "fmt"
     8  
     9  type Vec4 [4]float32
    10  
    11  func (v Vec4) String() string {
    12  	return fmt.Sprintf("Vec4[% 0.3f, % 0.3f, % 0.3f, % 0.3f]", v[0], v[1], v[2], v[3])
    13  }
    14  
    15  func (v *Vec4) Normalize() {
    16  	sq := v.Dot(v)
    17  	inv := 1 / Sqrt(sq)
    18  	v[0] *= inv
    19  	v[1] *= inv
    20  	v[2] *= inv
    21  	v[3] *= inv
    22  }
    23  
    24  func (v *Vec4) Sub(v0, v1 *Vec4) {
    25  	v[0] = v0[0] - v1[0]
    26  	v[1] = v0[1] - v1[1]
    27  	v[2] = v0[2] - v1[2]
    28  	v[3] = v0[3] - v1[3]
    29  }
    30  
    31  func (v *Vec4) Add(v0, v1 *Vec4) {
    32  	v[0] = v0[0] + v1[0]
    33  	v[1] = v0[1] + v1[1]
    34  	v[2] = v0[2] + v1[2]
    35  	v[3] = v0[3] + v1[3]
    36  }
    37  
    38  func (v *Vec4) Mul(v0, v1 *Vec4) {
    39  	v[0] = v0[0] * v1[0]
    40  	v[1] = v0[1] * v1[1]
    41  	v[2] = v0[2] * v1[2]
    42  	v[3] = v0[3] * v1[3]
    43  }
    44  
    45  func (v *Vec4) Dot(v1 *Vec4) float32 {
    46  	return v[0]*v1[0] + v[1]*v1[1] + v[2]*v1[2] + v[3]*v1[3]
    47  }