1 | /* |
2 | SPDX-FileCopyrightText: 2021 Volker Krause <vkrause@kde.org> |
3 | |
4 | SPDX-License-Identifier: LGPL-2.0-or-later |
5 | */ |
6 | |
7 | #ifndef SPATIAL_INDEX_ENTRY_P_H |
8 | #define SPATIAL_INDEX_ENTRY_P_H |
9 | |
10 | #include <cstdint> |
11 | |
12 | #pragma pack(push) |
13 | #pragma pack(1) |
14 | |
15 | /** Entry in the spatial index. |
16 | * This is essentially just a pair of numbers, the first being the position |
17 | * on the z-order curve and defines the order, the second being the index into the |
18 | * property table. |
19 | * |
20 | * These entries exist in very large quantities, so compact storage is important. |
21 | */ |
22 | class SpatialIndexEntry |
23 | { |
24 | public: |
25 | inline constexpr SpatialIndexEntry(uint32_t z, uint32_t propertyIdx) |
26 | : m_z(z) |
27 | , m_unused(0) |
28 | , m_propHigh(propertyIdx >> 8) |
29 | , m_propLow(propertyIdx) |
30 | { |
31 | } |
32 | |
33 | inline constexpr uint32_t z() const |
34 | { |
35 | return m_z; |
36 | } |
37 | |
38 | inline constexpr uint32_t propertyIndex() const |
39 | { |
40 | return m_propHigh << 8 | m_propLow; |
41 | } |
42 | |
43 | private: |
44 | uint32_t m_z : 22; |
45 | [[maybe_unused]] uint32_t m_unused : 6; |
46 | uint32_t m_propHigh : 4; |
47 | uint8_t m_propLow; |
48 | }; |
49 | |
50 | #pragma pack(pop) |
51 | |
52 | inline constexpr bool operator<(SpatialIndexEntry lhs, SpatialIndexEntry rhs) |
53 | { |
54 | return lhs.z() < rhs.z(); |
55 | } |
56 | |
57 | inline constexpr bool operator<(SpatialIndexEntry lhs, uint32_t rhs) |
58 | { |
59 | return lhs.z() < rhs; |
60 | } |
61 | |
62 | inline constexpr bool operator<(uint32_t lhs, SpatialIndexEntry rhs) |
63 | { |
64 | return lhs < rhs.z(); |
65 | } |
66 | |
67 | #endif |
68 | |