Files
ab_glyph_rasterizer
addr2line
adler
andrew
approx
arrayvec
ash
atom
backtrace
bitflags
byteorder
calloop
cfg_if
colorful
conrod_core
conrod_derive
conrod_example_shared
conrod_gfx
conrod_glium
conrod_piston
conrod_rendy
conrod_vulkano
conrod_wgpu
conrod_winit
copyless
copypasta
crossbeam
crossbeam_channel
crossbeam_deque
crossbeam_epoch
crossbeam_queue
crossbeam_utils
daggy
dlib
downcast_rs
draw_state
either
fixedbitset
float
fnv
futures
futures_channel
futures_core
futures_executor
futures_io
futures_macro
futures_sink
futures_task
futures_util
async_await
future
io
lock
sink
stream
task
fxhash
getrandom
gfx
gfx_backend_empty
gfx_backend_vulkan
gfx_core
gfx_descriptor
gfx_hal
gfx_memory
gimli
glium
glutin
glutin_egl_sys
glutin_glx_sys
graphics
half
hibitset
inplace_it
input
instant
interpolation
iovec
itoa
lazy_static
lazycell
libc
libloading
line_drawing
linked_hash_map
lock_api
log
maybe_uninit
memchr
memmap
memoffset
miniz_oxide
mio
mio_extras
naga
net2
nix
nom
num
num_bigint
num_complex
num_cpus
num_integer
num_iter
num_rational
num_traits
object
once_cell
ordered_float
ordermap
osmesa_sys
owned_ttf_parser
parking_lot
parking_lot_core
percent_encoding
petgraph
pin_project
pin_project_internal
pin_project_lite
pin_utils
ppv_lite86
proc_macro2
proc_macro_hack
proc_macro_nested
quote
rand
rand_chacha
rand_core
raw_window_handle
read_color
relevant
rendy
rendy_chain
rendy_command
rendy_core
rendy_descriptor
rendy_factory
rendy_frame
rendy_graph
rendy_init
rendy_memory
rendy_mesh
rendy_resource
rendy_shader
rendy_texture
rendy_wsi
rustc_demangle
rustc_hash
rusttype
ryu
same_file
scoped_tls
scopeguard
serde
serde_derive
serde_json
shaderc
shaderc_sys
shared_library
slab
smallvec
smithay_client_toolkit
smithay_clipboard
spirv_headers
stb_truetype
syn
takeable_option
texture
thiserror
thiserror_impl
thread_profiler
time
tracing
tracing_core
ttf_parser
typed_arena
unicode_xid
vecmath
viewport
vk_sys
void
vulkano
buffer
command_buffer
descriptor
device
framebuffer
image
instance
memory
pipeline
query
swapchain
sync
vulkano_shaders
walkdir
wayland_client
wayland_commons
wayland_cursor
wayland_egl
wayland_protocols
wayland_sys
wgpu
wgpu_core
wgpu_types
winit
x11
x11_clipboard
x11_dl
xcb
xcursor
xdg
xml
  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
#![deny(missing_docs)]

//! A simple library for reading hex colors.

use std::str::Chars;

/// Converts a character into a u8 value.
pub fn char_to_hex(ch: char) -> Option<u8> {
    Some(match ch {
        '0' => 0,
        '1' => 1,
        '2' => 2,
        '3' => 3,
        '4' => 4,
        '5' => 5,
        '6' => 6,
        '7' => 7,
        '8' => 8,
        '9' => 9,
        'A' | 'a' => 10,
        'B' | 'b' => 11,
        'C' | 'c' => 12,
        'D' | 'd' => 13,
        'E' | 'e' => 14,
        'F' | 'f' => 15,
        _ => { return None; }
    })
}

/// Reads a hex value from an iterator of characters.
pub fn hex(chars: &mut Chars) -> Option<u8> {
    match chars.next() {
        None => { return None; }
        Some(ch) => char_to_hex(ch)
    }
}

/// Reads a pair of hex values, joining them in value range 0-255.
pub fn hex_pair(chars: &mut Chars) -> Option<u8> {
    let h1 = match hex(chars) {
        None => { return None; }
        Some(h1) => h1
    };
    let h2 = match hex(chars) {
        None => { return None; }
        Some(h2) => h2
    };
    Some((h1 << 4) | h2)
}

/// Reads RGB colors from iterator of characters.
pub fn rgb(chars: &mut Chars) -> Option<[u8; 3]> {
    let red = match hex_pair(chars) {
        None => { return None; }
        Some(x) => x
    };
    let green = match hex_pair(chars) {
        None => { return None; }
        Some(x) => x
    };
    let blue = match hex_pair(chars) {
        None => { return None; }
        Some(x) => x
    };
    Some([red, green, blue])
}

/// Reads RGBA colors from iterator of characters.
pub fn rgba(chars: &mut Chars) -> Option<[u8; 4]> {
    let red = match hex_pair(chars) {
        None => { return None; }
        Some(x) => x
    };
    let green = match hex_pair(chars) {
        None => { return None; }
        Some(x) => x
    };
    let blue = match hex_pair(chars) {
        None => { return None; }
        Some(x) => x
    };
    let alpha = match hex_pair(chars) {
        None => { return None; }
        Some(x) => x
    };
    Some([red, green, blue, alpha])
}

/// Reads RGB with optional alpha from iterator of characters.
pub fn rgb_maybe_a(chars: &mut Chars) -> Option<([u8; 3], Option<u8>)> {
    let rgb = match rgb(chars) {
        None => { return None; }
        Some(x) => x
    };
    let a = match hex_pair(chars) {
        None => { return Some((rgb, None)); }
        Some(x) => x
    };
    Some((rgb, Some(a)))
}