arcdps_imgui/
internal.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
//! Internal raw utilities (don't use unless you know what you're doing!)

use std::slice;

/// A generic version of the raw imgui-sys ImVector struct types
#[repr(C)]
pub struct ImVector<T> {
    size: i32,
    capacity: i32,
    pub(crate) data: *mut T,
}

impl<T> ImVector<T> {
    #[inline]
    pub fn as_slice(&self) -> &[T] {
        unsafe { slice::from_raw_parts(self.data, self.size as usize) }
    }
}

#[test]
#[cfg(test)]
fn test_imvector_memory_layout() {
    use std::mem;
    assert_eq!(
        mem::size_of::<ImVector<u8>>(),
        mem::size_of::<sys::ImVector_char>()
    );
    assert_eq!(
        mem::align_of::<ImVector<u8>>(),
        mem::align_of::<sys::ImVector_char>()
    );
    use sys::ImVector_char;
    type VectorChar = ImVector<u8>;
    macro_rules! assert_field_offset {
        ($l:ident, $r:ident) => {
            assert_eq!(
                memoffset::offset_of!(VectorChar, $l),
                memoffset::offset_of!(ImVector_char, $r)
            );
        };
    }
    assert_field_offset!(size, Size);
    assert_field_offset!(capacity, Capacity);
    assert_field_offset!(data, Data);
}

/// Marks a type as a transparent wrapper over a raw type
pub trait RawWrapper {
    /// Wrapped raw type
    type Raw;
    /// Returns an immutable reference to the wrapped raw value
    ///
    /// # Safety
    ///
    /// It is up to the caller to use the returned raw reference without causing undefined
    /// behaviour or breaking safety rules.
    unsafe fn raw(&self) -> &Self::Raw;
    /// Returns a mutable reference to the wrapped raw value
    ///
    /// # Safety
    ///
    /// It is up to the caller to use the returned mutable raw reference without causing undefined
    /// behaviour or breaking safety rules.
    unsafe fn raw_mut(&mut self) -> &mut Self::Raw;
}

/// Casting from/to a raw type that has the same layout and alignment as the target type
pub unsafe trait RawCast<T>: Sized {
    /// Casts an immutable reference from the raw type
    ///
    /// # Safety
    ///
    /// It is up to the caller to guarantee the cast is valid.
    #[inline]
    unsafe fn from_raw(raw: &T) -> &Self {
        &*(raw as *const _ as *const Self)
    }
    /// Casts a mutable reference from the raw type
    ///
    /// # Safety
    ///
    /// It is up to the caller to guarantee the cast is valid.
    #[inline]
    unsafe fn from_raw_mut(raw: &mut T) -> &mut Self {
        &mut *(raw as *mut _ as *mut Self)
    }
    /// Casts an immutable reference to the raw type
    ///
    /// # Safety
    ///
    /// It is up to the caller to guarantee the cast is valid.
    #[inline]
    unsafe fn raw(&self) -> &T {
        &*(self as *const _ as *const T)
    }
    /// Casts a mutable reference to the raw type
    ///
    /// # Safety
    ///
    /// It is up to the caller to guarantee the cast is valid.
    #[inline]
    unsafe fn raw_mut(&mut self) -> &mut T {
        &mut *(self as *mut _ as *mut T)
    }
}

/// A primary data type
#[repr(u32)]
#[derive(Copy, Clone, Debug, Eq, PartialEq)]
pub enum DataType {
    I8 = sys::ImGuiDataType_S8,
    U8 = sys::ImGuiDataType_U8,
    I16 = sys::ImGuiDataType_S16,
    U16 = sys::ImGuiDataType_U16,
    I32 = sys::ImGuiDataType_S32,
    U32 = sys::ImGuiDataType_U32,
    I64 = sys::ImGuiDataType_S64,
    U64 = sys::ImGuiDataType_U64,
    F32 = sys::ImGuiDataType_Float,
    F64 = sys::ImGuiDataType_Double,
}

/// Primitive type marker.
///
/// If this trait is implemented for a type, it is assumed to have *exactly* the same
/// representation in memory as the primitive value described by the associated `KIND` constant.
pub unsafe trait DataTypeKind: Copy {
    const KIND: DataType;
}
unsafe impl DataTypeKind for i8 {
    const KIND: DataType = DataType::I8;
}
unsafe impl DataTypeKind for u8 {
    const KIND: DataType = DataType::U8;
}
unsafe impl DataTypeKind for i16 {
    const KIND: DataType = DataType::I16;
}
unsafe impl DataTypeKind for u16 {
    const KIND: DataType = DataType::U16;
}
unsafe impl DataTypeKind for i32 {
    const KIND: DataType = DataType::I32;
}
unsafe impl DataTypeKind for u32 {
    const KIND: DataType = DataType::U32;
}
unsafe impl DataTypeKind for i64 {
    const KIND: DataType = DataType::I64;
}
unsafe impl DataTypeKind for u64 {
    const KIND: DataType = DataType::U64;
}
unsafe impl DataTypeKind for f32 {
    const KIND: DataType = DataType::F32;
}
unsafe impl DataTypeKind for f64 {
    const KIND: DataType = DataType::F64;
}