1 /*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "common/math/vec.h"
18
findOrthogonalVector(float inX,float inY,float inZ,float * outX,float * outY,float * outZ)19 void findOrthogonalVector(float inX, float inY, float inZ, float *outX,
20 float *outY, float *outZ) {
21 ASSERT_NOT_NULL(outX);
22 ASSERT_NOT_NULL(outY);
23 ASSERT_NOT_NULL(outZ);
24 float x, y, z;
25
26 // discard the one with the smallest absolute value
27 if (fabsf(inX) <= fabsf(inY) && fabsf(inX) <= fabsf(inZ)) {
28 x = 0.0f;
29 y = inZ;
30 z = -inY;
31 } else if (fabsf(inY) <= fabsf(inZ)) {
32 x = inZ;
33 y = 0.0f;
34 z = -inX;
35 } else {
36 x = inY;
37 y = -inX;
38 z = 0.0f;
39 }
40
41 float magSquared = x * x + y * y + z * z;
42 ASSERT(magSquared > 0);
43 // Only set invMag if magSquared is non-zero.
44 float invMag = 1.0f;
45 if (magSquared > 0) {
46 invMag = 1.0f / sqrtf(magSquared);
47 }
48 *outX = x * invMag;
49 *outY = y * invMag;
50 *outZ = z * invMag;
51 }
52
vecAdd(float * u,const float * v,const float * w,int dim)53 void vecAdd(float *u, const float *v, const float *w, int dim) {
54 ASSERT_NOT_NULL(u);
55 ASSERT_NOT_NULL(v);
56 ASSERT_NOT_NULL(w);
57 int i;
58 for (i = 0; i < dim; i++) {
59 u[i] = v[i] + w[i];
60 }
61 }
62
vecAddInPlace(float * v,const float * w,int dim)63 void vecAddInPlace(float *v, const float *w, int dim) {
64 ASSERT_NOT_NULL(v);
65 ASSERT_NOT_NULL(w);
66 int i;
67 for (i = 0; i < dim; i++) {
68 v[i] += w[i];
69 }
70 }
71
vecSub(float * u,const float * v,const float * w,int dim)72 void vecSub(float *u, const float *v, const float *w, int dim) {
73 ASSERT_NOT_NULL(u);
74 ASSERT_NOT_NULL(v);
75 ASSERT_NOT_NULL(w);
76 int i;
77 for (i = 0; i < dim; i++) {
78 u[i] = v[i] - w[i];
79 }
80 }
81
vecScalarMul(float * u,const float * v,float c,int dim)82 void vecScalarMul(float *u, const float *v, float c, int dim) {
83 ASSERT_NOT_NULL(u);
84 ASSERT_NOT_NULL(v);
85 int i;
86 for (i = 0; i < dim; i++) {
87 u[i] = c * v[i];
88 }
89 }
90
vecScalarMulInPlace(float * u,float c,int dim)91 void vecScalarMulInPlace(float *u, float c, int dim) {
92 ASSERT_NOT_NULL(u);
93 int i;
94 for (i = 0; i < dim; i++) {
95 u[i] *= c;
96 }
97 }
98
vecNorm(const float * v,int dim)99 float vecNorm(const float *v, int dim) {
100 ASSERT_NOT_NULL(v);
101 float norm_sq = vecNormSquared(v, dim);
102 return sqrtf(norm_sq);
103 }
104
vecNormSquared(const float * v,int dim)105 float vecNormSquared(const float *v, int dim) {
106 ASSERT_NOT_NULL(v);
107 return vecDot(v, v, dim);
108 }
109
vecDot(const float * v,const float * w,int dim)110 float vecDot(const float *v, const float *w, int dim) {
111 ASSERT_NOT_NULL(v);
112 ASSERT_NOT_NULL(w);
113 int i;
114 float result = 0;
115 for (i = 0; i < dim; ++i) {
116 result += v[i] * w[i];
117 }
118 return result;
119 }
120
vecMaxAbsoluteValue(const float * v,int dim)121 float vecMaxAbsoluteValue(const float *v, int dim) {
122 ASSERT_NOT_NULL(v);
123 float max = NANO_ABS(v[0]);
124 float tmp;
125 int i;
126 for (i = 1; i < dim; ++i) {
127 tmp = NANO_ABS(v[i]);
128 if(tmp > max) {
129 max = tmp;
130 }
131 }
132 return max;
133 }
134