Add line of sight

4 files changed, 373 insertions, 20 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 544bfbb..a59e743 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,16 +1,69 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
 [[package]]
+name = "arrayref"
+version = "0.3.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "arrayvec"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "autocfg"
 version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "backtrace"
+version = "0.3.40"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "backtrace-sys 0.1.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.58 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-demangle 0.1.16 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "backtrace-sys"
+version = "0.1.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cc 1.0.48 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.58 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "bitflags"
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 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "blake2b_simd"
+version = "0.5.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "arrayref 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "arrayvec 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "constant_time_eq 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
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@@ -20,11 +73,48 @@ dependencies = [
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 [[package]]
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+version = "1.0.48"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
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 [[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "num-integer 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-traits 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
+ "time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "cloudabi"
+version = "0.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "constant_time_eq"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "crossbeam-utils"
+version = "0.6.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
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@@ -45,6 +135,51 @@ dependencies = [
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 [[package]]
+name = "dirs"
+version = "2.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "dirs-sys 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "dirs-sys"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.58 (registry+https://github.com/rust-lang/crates.io-index)",
+ "redox_users 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "failure"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "backtrace 0.3.40 (registry+https://github.com/rust-lang/crates.io-index)",
+ "failure_derive 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "failure_derive"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.12 (registry+https://github.com/rust-lang/crates.io-index)",
+ "synstructure 0.12.3 (registry+https://github.com/rust-lang/crates.io-index)",
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+
+[[package]]
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+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
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@@ -149,11 +284,44 @@ dependencies = [
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
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+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
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+
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 [[package]]
+name = "proc-macro2"
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
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+
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro2 1.0.7 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
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@@ -177,6 +345,19 @@ dependencies = [
 
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
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+
+[[package]]
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+
+[[package]]
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@@ -192,16 +373,80 @@ dependencies = [
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
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+ "libc 0.2.58 (registry+https://github.com/rust-lang/crates.io-index)",
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+ "rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
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+
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+
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 [[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
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+
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+
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@@ -212,11 +457,56 @@ version = "0.5.0"
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diff --git a/Cargo.toml b/Cargo.toml
index bf635a7..1255fad 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,3 +9,5 @@ rand = "0.7.0"
 text_io = "0.1.7"
 crossterm = "0.13.3"
 ignore-result = "0.2.0"
+log = "0.4"
+simplelog = "0.7"
diff --git a/src/main.rs b/src/main.rs
index e45701a..d00db53 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,23 +1,22 @@
-extern crate crossterm;
-extern crate ignore_result;
-extern crate rand;
-extern crate text_io;
-
 mod entities;
 mod state;
 mod tiling;
 mod world;
 
+use std::env;
+use std::fs::File;
+use std::io::{stdout, Write};
+
 use crossterm::cursor;
 use crossterm::execute;
 use crossterm::input::{input, InputEvent, KeyEvent};
 use crossterm::screen::{EnterAlternateScreen, LeaveAlternateScreen, RawScreen};
 use crossterm::terminal;
-use entities::Player;
 use ignore_result::Ignore;
+use simplelog::*;
+
+use entities::Player;
 use state::State;
-use std::env;
-use std::io::{stdout, Write};
 use world::{Dungeon, DOWN, LEFT, RIGHT, UP};
 
 fn player_name() -> String {
@@ -28,23 +27,35 @@ fn player_name() -> String {
 }
 
 fn main() {
+    // Set up the debug logger only if required.
+    if let Ok(_val) = env::var("DEBUG") {
+        WriteLogger::init(
+            LevelFilter::Debug,
+            Config::default(),
+            File::create("roguerust.log").unwrap(),
+        )
+        .unwrap();
+    }
+
+    // Initialise the terminal, the raw alternate mode allows direct character
+    // seeking and hides the prompt.
     let term_size = terminal::size().unwrap();
+    execute!(stdout(), EnterAlternateScreen).unwrap();
+    execute!(stdout(), cursor::Hide).unwrap();
+    let _raw = RawScreen::into_raw_mode();
 
+    // Initialise state, create the player and dungeon
     let mut state = State::new(
         Player::new(player_name(), String::from("Warrior"), 30, 10, 10, 20),
         Dungeon::new(term_size.0 as usize, (term_size.1 - 2) as usize, 5),
     );
-
     state.init();
 
-    execute!(stdout(), EnterAlternateScreen).unwrap();
-    execute!(stdout(), cursor::Hide).unwrap();
-
-    let _raw = RawScreen::into_raw_mode();
-
     let input = input();
     let mut reader = input.read_sync();
 
+    // Main loop, dispatches events and calls rendering routines. Don't
+    // add any game logic here.
     loop {
         state.render_player();
         state.render_level();
diff --git a/src/tiling.rs b/src/tiling.rs
index f2a9b02..17e8f32 100644
--- a/src/tiling.rs
+++ b/src/tiling.rs
@@ -1,3 +1,4 @@
+use log::debug;
 use std::convert::From;
 
 #[derive(Clone)]
@@ -103,6 +104,10 @@ impl TileGrid {
         self.ysize
     }
 
+    fn reveal(&mut self, x: usize, y: usize) {
+        self.grid[y][x].visibility(true);
+    }
+
     /// Clears all blocks in a single line of sight ray; stop when encountering a wall
     /// This uses the bresenham algorithm, see:
     ///     https://en.wikipedia.org/wiki/Bresenham%27s_line_algorithm
@@ -116,11 +121,15 @@ impl TileGrid {
         let mut x = start.0;
         let mut y = start.1;
 
+        // the tile we're standing on needs to be visible.
+        self.reveal(start.0, start.1);
+
         loop {
             if x == end.0 && y == end.1 {
+                self.reveal(x, y);
                 break;
             }
-            if let TileType::Wall = self.grid[y][x].get_type() {
+            if let TileType::Empty = self.grid[y][x].get_type() {
                 break;
             }
 
@@ -133,7 +142,7 @@ impl TileGrid {
                 err += dx;
                 y = (y as isize + sy).max(0) as usize;
             }
-            self.grid[y][x].visibility(true);
+            self.reveal(x, y);
         }
     }
 
@@ -148,20 +157,26 @@ impl TileGrid {
         let c = (center.0 + radius, center.1 + radius);
         let d = (center.0.saturating_sub(radius), center.1 + radius);
 
+        debug!("LOS: {:?} - {:?} {:?} {:?} {:?}", center, a, b, c, d);
+
         // From a to b
-        for x in a.0..b.0 {
+        for x in a.0..=b.0 {
+            // debug!("Clear LOS from {:?} to {:?}", center, (x, a.1));
             self.clear_los(center, &(x, a.1));
         }
         // From b to c
-        for y in b.1..c.1 {
+        for y in b.1..=c.1 {
+            // debug!("Clear LOS from {:?} to {:?}", center, (b.0, y));
             self.clear_los(center, &(b.0, y));
         }
         // From c to d
-        for x in d.0..c.0 {
+        for x in d.0..=c.0 {
+            // debug!("Clear LOS from {:?} to {:?}", center, (x, c.1));
             self.clear_los(center, &(x, c.1));
         }
         // From d to a
-        for y in a.1..d.1 {
+        for y in a.1..=d.1 {
+            // debug!("Clear LOS from {:?} to {:?}", center, (d.0, y));
             self.clear_los(center, &(d.0, y));
         }
     }