libs/base/src/eu/base/transform.cc - GCC Code Coverage Report

libs/base/src/eu/base/transform.cc

Line	Branch	Exec	Source
1			#include "eu/base/transform.h"
2
3			#include <cmath>
4			#include <algorithm>
5
6			namespace eu
7			{
8			namespace
9			{
10			template <typename T, size_t array_size>
11		58	size_t argmax(const std::array<T, array_size>& array)
12			{
13	1/6 ✗ Branch 6 → 7 not taken. ✓ Branch 6 → 13 taken 58 times. ✗ Branch 8 → 9 not taken. ✗ Branch 8 → 13 not taken. ✗ Branch 10 → 11 not taken. ✗ Branch 10 → 25 not taken.	58	ASSERT(array.empty() == false);
14		116	return std::distance(array.begin(), std::max_element(array.begin(), array.end()));
15			}
16
17			/// Implements the "Shepperd's method" as described in
18			/// "3-D Computer Graphics A Mathematical Introduction with OpenGL" by Samuel R. Buss (2022)
19			/// in section XII 3.6 Quaternion and rotation matrix conversions on page 465
20			Q
21		58	quat_from_rotation_matrix(const m4& m)
22			{
23		58	const auto m11 = m.get(0, 0);
24		58	const auto m22 = m.get(1, 1);
25		58	const auto m33 = m.get(2, 2);
26
27			// aka trace
28		58	const auto m00 = m11 + m22 + m33;
29
30	3/7 ✓ Branch 5 → 6 taken 58 times. ✗ Branch 5 → 56 not taken. ✓ Branch 6 → 7 taken 57 times. ✗ Branch 6 → 18 not taken. ✓ Branch 6 → 29 taken 1 time. ✗ Branch 6 → 40 not taken. ✗ Branch 6 → 51 not taken.	58	switch (argmax(std::array{ m00, m11, m22, m33 }))
31			{
32		57	case 0:
33			{
34		57	const auto d = 0.5f * std::sqrt(m00 + 1.0f);
35
36		57	const auto a = (m.get1(3, 2) - m.get1(2, 3)) / (4.0f * d);
37		57	const auto b = (m.get1(1, 3) - m.get1(3, 1)) / (4.0f * d);
38		57	const auto c = (m.get1(2, 1) - m.get1(1, 2)) / (4.0f * d);
39
40		57	return Q{ d, {a, b, c} };
41			}
42		✗	case 1:
43			{
44		✗	const auto a = 0.5f * std::sqrt(2.0f * m11 - m00 + 1.0f);
45
46		✗	const auto d = (m.get1(3, 2) - m.get1(2, 3)) / (4.0f * a);
47		✗	const auto b = (m.get1(2, 1) + m.get1(1, 2)) / (4.0f * a);
48		✗	const auto c = (m.get1(1, 3) + m.get1(3, 1)) / (4.0f * a);
49
50		✗	return Q{ d, {a, b, c} };
51			}
52		1	case 2:
53			{
54		1	const auto b = 0.5f * std::sqrt(2.0f * m22 - m00 + 1.0f);
55
56		1	const auto d = (m.get1(1, 3) - m.get1(3, 1)) / (4.0f * b);
57		1	const auto a = (m.get1(2, 1) + m.get1(1, 2)) / (4.0f * b);
58		1	const auto c = (m.get1(3, 2) + m.get1(2, 3)) / (4.0f * b);
59
60		1	return Q{ d, {a, b, c} };
61			}
62		✗	case 3:
63			{
64		✗	const auto c = 0.5f * std::sqrt(2.0f * m33 - m00 + 1.0f);
65
66		✗	const auto d = (m.get1(2, 1) - m.get1(1, 2)) / (4.0f * c);
67		✗	const auto a = (m.get1(1, 3) + m.get1(3, 1)) / (4.0f * c);
68		✗	const auto b = (m.get1(3, 2) + m.get1(2, 3)) / (4.0f * c);
69
70		✗	return Q{ d, {a, b, c} };
71			}
72		✗	default:
73		✗	DIE("shouldn't happen!!!");
74		✗	return q_identity;
75			}
76			}
77			}
78
79
80			Transform
81		58	transform_from_matrix(const m4& m)
82			{
83			// heavily inspired by DecomposeMatrixToComponents from imguizmo
84	2/4 ✓ Branch 2 → 3 taken 58 times. ✗ Branch 2 → 24 not taken. ✓ Branch 3 → 4 taken 58 times. ✗ Branch 3 → 24 not taken.	58	const auto right = m.get_column(0).to_vec3(0.0f);
85	2/4 ✓ Branch 4 → 5 taken 58 times. ✗ Branch 4 → 25 not taken. ✓ Branch 5 → 6 taken 58 times. ✗ Branch 5 → 25 not taken.	58	const auto up = m.get_column(1).to_vec3(0.0f);
86	2/4 ✓ Branch 6 → 7 taken 58 times. ✗ Branch 6 → 26 not taken. ✓ Branch 7 → 8 taken 58 times. ✗ Branch 7 → 26 not taken.	58	const auto out = m.get_column(2).to_vec3(0.0f);
87
88			const auto scale = v3
89			{
90			right.get_length(),
91			up.get_length(),
92			out.get_length()
93	3/6 ✓ Branch 8 → 9 taken 58 times. ✗ Branch 8 → 31 not taken. ✓ Branch 9 → 10 taken 58 times. ✗ Branch 9 → 31 not taken. ✓ Branch 10 → 11 taken 58 times. ✗ Branch 10 → 31 not taken.	58	};
94
95			// orthonormalize the basis to drop the scale
96	1/2 ✓ Branch 12 → 13 taken 58 times. ✗ Branch 12 → 27 not taken.	58	const auto normalized_right = right.get_normalized().value_or(kk::right);
97	1/2 ✓ Branch 14 → 15 taken 58 times. ✗ Branch 14 → 28 not taken.	58	const auto normalized_up = up.get_normalized().value_or(kk::up);
98	1/2 ✓ Branch 16 → 17 taken 58 times. ✗ Branch 16 → 29 not taken.	58	const auto normalized_out = out.get_normalized().value_or(kk::out);
99
100	1/2 ✓ Branch 18 → 19 taken 58 times. ✗ Branch 18 → 31 not taken.	58	const auto rotation_matrix = m4::from_basis(normalized_right, normalized_up, normalized_out);
101
102			return
103			{
104	1/2 ✓ Branch 19 → 20 taken 58 times. ✗ Branch 19 → 31 not taken.	58	.position = m.get_translation(),
105	2/4 ✓ Branch 20 → 21 taken 58 times. ✗ Branch 20 → 30 not taken. ✓ Branch 21 → 22 taken 58 times. ✗ Branch 21 → 30 not taken.	58	.rotation = quat_from_rotation_matrix(rotation_matrix).get_normalized(),
106			.scale = scale
107		58	};
108			}
109
110
111			m4
112		113	matrix_from_transform(const Transform& t)
113			{
114			// heavily inspired by RecomposeMatrixFromComponents from imguizmo
115
116			const auto rotation = m4::from_basis
117	1/2 ✓ Branch 5 → 6 taken 113 times. ✗ Branch 5 → 13 not taken.	113	(
118	1/2 ✓ Branch 4 → 5 taken 113 times. ✗ Branch 4 → 13 not taken.	113	t.rotation.get_local_right(),
119	1/2 ✓ Branch 3 → 4 taken 113 times. ✗ Branch 3 → 14 not taken.	113	t.rotation.get_local_up(),
120	1/2 ✓ Branch 2 → 3 taken 113 times. ✗ Branch 2 → 15 not taken.	113	t.rotation.get_local_out()
121			);
122
123	4/8 ✓ Branch 6 → 7 taken 113 times. ✗ Branch 6 → 18 not taken. ✓ Branch 7 → 8 taken 113 times. ✗ Branch 7 → 16 not taken. ✓ Branch 8 → 9 taken 113 times. ✗ Branch 8 → 16 not taken. ✓ Branch 9 → 10 taken 113 times. ✗ Branch 9 → 16 not taken.	113	return m4::from_translation(t.position) * rotation * m4::from_scale(t.scale);
124			}
125			}
126