d3df5eca0b
Also fix String methods' receivers to be T, not *T, so that
var m f32.Mat32
s := fmt.Sprintf("m=%v", m)
works.
LGTM=crawshaw
R=crawshaw
CC=golang-codereviews
https://golang.org/cl/147490043
49 lines
1.2 KiB
Go
49 lines
1.2 KiB
Go
// Copyright 2014 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 f32
|
||
|
||
import "fmt"
|
||
|
||
// An Affine is a 3x3 matrix of float32 values for which the bottom row is
|
||
// implicitly always equal to [0 0 1].
|
||
// Elements are indexed first by row then column, i.e. m[row][column].
|
||
type Affine [2]Vec3
|
||
|
||
func (m Affine) String() string {
|
||
return fmt.Sprintf(`Affine[% 0.3f, % 0.3f, % 0.3f,
|
||
% 0.3f, % 0.3f, % 0.3f]`,
|
||
m[0][0], m[0][1], m[0][2],
|
||
m[1][0], m[1][1], m[1][2])
|
||
}
|
||
|
||
func (m *Affine) Identity() {
|
||
*m = Affine{
|
||
{1, 0, 0},
|
||
{0, 1, 0},
|
||
}
|
||
}
|
||
|
||
func (m *Affine) Eq(n *Affine, epsilon float32) bool {
|
||
for i := range m {
|
||
for j := range m[i] {
|
||
diff := m[i][j] - n[i][j]
|
||
if diff < -epsilon || +epsilon < diff {
|
||
return false
|
||
}
|
||
}
|
||
}
|
||
return true
|
||
}
|
||
|
||
// Mul stores m0 × m1 in m.
|
||
func (m *Affine) Mul(m0, m1 *Affine) {
|
||
m[0][0] = m0[0][0]*m1[0][0] + m0[0][1]*m1[1][0]
|
||
m[0][1] = m0[0][0]*m1[0][1] + m0[0][1]*m1[1][1]
|
||
m[0][2] = m0[0][0]*m1[0][2] + m0[0][1]*m1[1][2] + m0[0][2]
|
||
m[1][0] = m0[1][0]*m1[0][0] + m0[1][1]*m1[1][0]
|
||
m[1][1] = m0[1][0]*m1[0][1] + m0[1][1]*m1[1][1]
|
||
m[1][2] = m0[1][0]*m1[0][2] + m0[1][1]*m1[1][2] + m0[1][2]
|
||
}
|