git.seregonwar.com

common/number_utils.cpp

ShadPKG / common / number_utils.cpp

1	// SPDX-FileCopyrightText: Copyright 2024 shadPS4 Emulator Project
2	// SPDX-License-Identifier: GPL-2.0-or-later
3
4	#include <array>
5	#include <half.hpp>
6
7	#include "common/number_utils.h"
8	#include "video_core/amdgpu/pixel_format.h"
9	#include "video_core/amdgpu/types.h"
10
11	#define UF11_EXPONENT_SHIFT 6
12	#define UF10_EXPONENT_SHIFT 5
13
14	#define RGB9E5_MANTISSA_BITS 9
15	#define RGB9E5_EXP_BIAS 1
16
17	#define F32_INFINITY 0x7f800000
18
19	namespace NumberUtils {
20
21	float Uf11ToF32(u16 val) {
22	union {
23	float f;
24	u32 ui;
25	} f32;
26
27	int exponent = (val & 0x07c0) >> UF11_EXPONENT_SHIFT;
28	int mantissa = (val & 0x003f);
29
30	f32.f = 0.0;
31
32	if (exponent == 0) {
33	if (mantissa != 0) {
34	const float scale = 1.0 / (1 << 20);
35	f32.f = scale * mantissa;
36	}
37	} else if (exponent == 31) {
38	f32.ui = F32_INFINITY \| mantissa;
39	} else {
40	float scale, decimal;
41	exponent -= 15;
42	if (exponent < 0) {
43	scale = 1.0f / (1 << -exponent);
44	} else {
45	scale = (float)(1 << exponent);
46	}
47	decimal = 1.0f + (float)mantissa / 64;
48	f32.f = scale * decimal;
49	}
50
51	return f32.f;
52	}
53
54	float Uf10ToF32(u16 val) {
55	union {
56	float f;
57	u32 ui;
58	} f32;
59
60	int exponent = (val & 0x03e0) >> UF10_EXPONENT_SHIFT;
61	int mantissa = (val & 0x001f);
62
63	f32.f = 0.0;
64
65	if (exponent == 0) {
66	if (mantissa != 0) {
67	const float scale = 1.0 / (1 << 19);
68	f32.f = scale * mantissa;
69	}
70	} else if (exponent == 31) {
71	f32.ui = F32_INFINITY \| mantissa;
72	} else {
73	float scale, decimal;
74	exponent -= 15;
75	if (exponent < 0) {
76	scale = 1.0f / (1 << -exponent);
77	} else {
78	scale = (float)(1 << exponent);
79	}
80	decimal = 1.0f + (float)mantissa / 32;
81	f32.f = scale * decimal;
82	}
83
84	return f32.f;
85	}
86
87	float Uf16ToF32(u16 val) {
88	return half_float::half_cast<float>(reinterpret_cast<half_float::half&>(val));
89	}
90
91	float U2ToUnorm(u8 val) {
92	static constexpr auto c = 1.0f / 3.0f;
93	return float(val * c);
94	}
95
96	float S2ToSnorm(s8 val) {
97	static constexpr auto c = 1.0f / 1.0f;
98	return float(val * c);
99	}
100
101	float U4ToUnorm(u8 val) {
102	static constexpr auto c = 1.0f / 15.0f;
103	return float(val * c);
104	}
105
106	float S4ToSnorm(s8 val) {
107	static constexpr auto c = 1.0f / 7.0f;
108	return float(val * c);
109	}
110
111	float U5ToUnorm(u8 val) {
112	static constexpr auto c = 1.0f / 31.0f;
113	return float(val * c);
114	}
115
116	float S5ToSnorm(s8 val) {
117	static constexpr auto c = 1.0f / 15.0f;
118	return float(val * c);
119	}
120
121	float U6ToUnorm(u8 val) {
122	static constexpr auto c = 1.0f / 63.0f;
123	return float(val * c);
124	}
125
126	float S6ToSnorm(s8 val) {
127	static constexpr auto c = 1.0f / 31.0f;
128	return float(val * c);
129	}
130
131	float U8ToUnorm(u8 val) {
132	static constexpr auto c = 1.0f / 255.0f;
133	return float(val * c);
134	}
135
136	float S8ToSnorm(s8 val) {
137	static constexpr auto c = 1.0f / 127.0f;
138	return float(val * c);
139	}
140
141	float U10ToUnorm(u16 val) {
142	static constexpr auto c = 1.0f / 1023.0f;
143	return float(val * c);
144	}
145
146	float S10ToSnorm(s16 val) {
147	static constexpr auto c = 1.0f / 511.0f;
148	return float(val * c);
149	}
150
151	float U16ToUnorm(u16 val) {
152	static constexpr auto c = 1.0f / 65535.0f;
153	return float(val * c);
154	}
155
156	float S16ToSnorm(s16 val) {
157	static constexpr auto c = 1.0f / 32767.0f;
158	return float(val * c);
159	}
160
161	} // namespace NumberUtils

Seregon/ShadPKG