world_file/
lib.rs

1// Copyright 2015 The GeoRust Developers
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//	http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15#![no_std]
16
17//! ```rust
18//! use world_file::WorldFile;
19//!
20//! let world_file_txt = "\
21//! 32.0
22//! 0.0
23//! 0.0
24//! -32.0
25//! 691200.0
26//! 4576000.0";
27//!
28//! let world_file: WorldFile = world_file_txt.parse().unwrap();
29//!
30//! assert_eq!(world_file.x_scale, 32.0);
31//! assert_eq!(world_file.y_skew, 0.0);
32//! assert_eq!(world_file.x_skew, 0.0);
33//! assert_eq!(world_file.y_scale, -32.0);
34//! assert_eq!(world_file.x_coord, 691200.0);
35//! assert_eq!(world_file.y_coord, 4576000.0);
36//! ```
37
38use core::str::FromStr;
39
40pub struct WorldFile {
41    pub x_scale: f64,
42    pub y_skew: f64,
43    pub x_skew: f64,
44    pub y_scale: f64,
45    pub x_coord: f64,
46    pub y_coord: f64,
47}
48
49impl FromStr for WorldFile {
50    type Err = ();
51    fn from_str(s: &str) -> Result<Self, ()> {
52        let mut lines = s.lines();
53
54        // size of pixel in x direction (x_scale)
55        let x_scale: f64 = match lines.next() {
56            Some(s) => match FromStr::from_str(s) {
57                Ok(i) => i,
58                Err(_) => return Err(()),
59            },
60            None => return Err(()),
61        };
62
63        // rotation term for row (y_skew)
64        let y_skew: f64 = match lines.next() {
65            Some(s) => match FromStr::from_str(s) {
66                Ok(i) => i,
67                Err(_) => return Err(()),
68            },
69            None => return Err(()),
70        };
71
72        // rotation term for column (x_skew)
73        let x_skew: f64 = match lines.next() {
74            Some(s) => match FromStr::from_str(s) {
75                Ok(i) => i,
76                Err(_) => return Err(()),
77            },
78            None => return Err(()),
79        };
80
81        // size of pixel in y direction (y_scale)
82        let y_scale: f64 = match lines.next() {
83            Some(s) => match FromStr::from_str(s) {
84                Ok(i) => i,
85                Err(_) => return Err(()),
86            },
87            None => return Err(()),
88        };
89
90        // x coordinate of centre of upper left pixel in map units (x_coord)
91        let x_coord: f64 = match lines.next() {
92            Some(s) => match FromStr::from_str(s) {
93                Ok(i) => i,
94                Err(_) => return Err(()),
95            },
96            None => return Err(()),
97        };
98
99        // y coordinate of centre of upper left pixel in map units (y_coord)
100        let y_coord: f64 = match lines.next() {
101            Some(s) => match FromStr::from_str(s) {
102                Ok(i) => i,
103                Err(_) => return Err(()),
104            },
105            None => return Err(()),
106        };
107
108        Ok(WorldFile {
109            x_scale: x_scale,
110            y_skew: y_skew,
111            x_skew: x_skew,
112            y_scale: y_scale,
113            x_coord: x_coord,
114            y_coord: y_coord,
115        })
116    }
117}
world_file/lib.rs

world_file/
lib.rs
