gl_utils/
texture.rs

1//! Texture related utilities.
2
3use std;
4use glium;
5use image;
6use log;
7
8/// An RGBA 16x16 square of pixels with white color values with an opaque cross of two
9/// pixels thickness
10pub const CROSSHAIR_PNG_FILE_BYTES                        : &[u8; 101] =
11  include_bytes!("../crosshair.png");
12/// For use with `BLEND_FUNC_INVERT_COLOR`-- transparent pixels have *black* color
13/// values instead of white but the opaque portion is still white
14pub const CROSSHAIR_INVERSE_PNG_FILE_BYTES                : &[u8; 95]  =
15  include_bytes!("../crosshair-inverse.png");
16pub const TILESET_EASCII_ACORN_8X8_PNG_FILE_BYTES         : &[u8; 2538] =
17  include_bytes!("../tileset_eascii_acorn-bbc-micro_8x8.png");
18pub const TILESET_EASCII_ACORN_8X8_INVERSE_PNG_FILE_BYTES : &[u8; 2526] =
19  include_bytes!("../tileset_eascii_acorn-bbc-micro_8x8-inverse.png");
20pub const TILESET_EASCII_ACORN_16X16_PNG_FILE_BYTES       : &[u8; 3427] =
21  include_bytes!("../tileset_eascii_acorn-bbc-micro_16x16.png");
22pub const TILESET_EASCII_ACORN_16X16_INVERSE_PNG_FILE_BYTES : &[u8; 3427] =
23  include_bytes!("../tileset_eascii_acorn-bbc-micro_16x16-inverse.png");
24pub const POINTER_HAND_PNG_FILE_BYTES_OFFSET : (&[u8; 183], [i16; 2]) =
25  (include_bytes!("../pointer-hand.png"), [3, -10]);
26
27#[derive(Debug)]
28pub enum LoadError {
29  IoError              (std::io::Error),
30  ImageError           (image::ImageError),
31  TextureCreationError (glium::texture::TextureCreationError)
32}
33
34/// Load a 2D texture from the given bytes with the given format and mipmaps.
35pub fn texture2d_with_mipmaps_from_bytes (
36  glium_facade : &dyn glium::backend::Facade,
37  bytes        : &[u8],
38  image_format : image::ImageFormat,
39  mipmaps      : glium::texture::MipmapsOption
40) -> Result <glium::Texture2d, LoadError> {
41  let img = image::load_from_memory_with_format (bytes, image_format)?.to_rgba8();
42  let img_dimensions = img.dimensions();
43  log::debug!(dimensions:?=img_dimensions; "texture load bytes");
44  let raw_image_2d = glium::texture::RawImage2d::from_raw_rgba_reversed (
45    img.into_raw().as_slice(), img_dimensions);
46
47  glium::Texture2d::with_mipmaps (glium_facade, raw_image_2d, mipmaps)
48    .map_err (Into::into)
49}
50
51/// Load a 2D texture from the given path with the given format and mipmaps.
52pub fn texture2d_with_mipmaps_from_file (
53  glium_facade : &dyn glium::backend::Facade,
54  filepath     : &'static str,
55  image_format : image::ImageFormat,
56  mipmaps      : glium::texture::MipmapsOption
57) -> Result <glium::Texture2d, LoadError> {
58  log::debug!(filepath:?; "texture load file");
59  let bytes = std::fs::read (filepath)?;
60  texture2d_with_mipmaps_from_bytes (
61    glium_facade, bytes.as_slice(), image_format, mipmaps)
62}
63
64/// Load a 2D texture array from the given vector of byte slices for each individual
65/// texture, with the given format and mipmaps.
66pub fn texture2darray_with_mipmaps_from_bytes (
67  glium_facade : &dyn glium::backend::Facade,
68  bytes_slices : &[&[u8]],
69  image_format : image::ImageFormat,
70  mipmaps      : glium::texture::MipmapsOption
71) -> Result <glium::texture::Texture2dArray, LoadError> {
72  let raw_images = {
73    let mut v = Vec::with_capacity (bytes_slices.len());
74    for bytes in bytes_slices {
75      let img = image::load_from_memory_with_format (bytes, image_format)?.to_rgba8();
76      let img_dimensions = img.dimensions();
77      log::debug!(dimensions:?=img_dimensions; "texture array load bytes");
78      let raw_image_2d = glium::texture::RawImage2d::from_raw_rgba_reversed (
79        img.into_raw().as_slice(), img_dimensions);
80      v.push (raw_image_2d);
81    }
82    v
83  };
84
85  glium::texture::Texture2dArray::with_mipmaps (glium_facade, raw_images, mipmaps)
86    .map_err (Into::into)
87}
88
89/// Load a 2D texture array from the given paths with the given format and mipmaps.
90pub fn texture2darray_with_mipmaps_from_files (
91  glium_facade : &dyn glium::backend::Facade,
92  filepaths    : &[&'static str],
93  image_format : image::ImageFormat,
94  mipmaps      : glium::texture::MipmapsOption
95) -> Result <glium::texture::Texture2dArray, LoadError> {
96  if filepaths.is_empty() {
97    return Err (std::io::Error::new (std::io::ErrorKind::InvalidInput,
98      "no input paths provided").into())
99  }
100
101  let bytes = {
102    let mut v = Vec::with_capacity (filepaths.len());
103    v.resize_with (filepaths.len(), Default::default);
104    for (i, filepath) in filepaths.iter().enumerate() {
105      log::debug!(filepath:?; "texture load file");
106      v[i] = std::fs::read (filepath)?;
107    }
108    v
109  };
110
111  let bytes_vec = {
112    let mut v = Vec::with_capacity (filepaths.len());
113    for bytes in bytes.iter() {
114      v.push (bytes.as_slice());
115    }
116    v
117  };
118
119  let texture2darray = texture2darray_with_mipmaps_from_bytes (
120    glium_facade, &bytes_vec, image_format, mipmaps)?;
121  // bytes must live until here
122  Ok (texture2darray)
123}
124
125//
126//  impls
127//
128impl std::fmt::Display for LoadError {
129  fn fmt (&self, f : &mut std::fmt::Formatter) -> std::fmt::Result {
130    match self {
131      LoadError::IoError              (err) => write!(f, "I/O error: {err}"),
132      LoadError::ImageError           (err) => err.fmt (f),
133      LoadError::TextureCreationError (err) => err.fmt (f)
134    }
135  }
136}
137
138impl std::error::Error for LoadError {
139  fn source (&self) -> Option <&(dyn std::error::Error + 'static)> {
140    match self {
141      LoadError::IoError              (err) => err.source(),
142      LoadError::ImageError           (err) => err.source(),
143      LoadError::TextureCreationError (err) => err.source()
144    }
145  }
146}
147
148impl From <std::io::Error> for LoadError {
149  fn from (err : std::io::Error) -> Self {
150    LoadError::IoError (err)
151  }
152}
153
154impl From <image::ImageError> for LoadError {
155  fn from (err : image::ImageError) -> Self {
156    LoadError::ImageError (err)
157  }
158}
159
160impl From <glium::texture::TextureCreationError> for LoadError {
161  fn from (err : glium::texture::TextureCreationError) -> Self {
162    LoadError::TextureCreationError (err)
163  }
164}
gl_utils/texture.rs

gl_utils/
texture.rs
