More work on chapter 7.

Cargo.lock

@@ -90,7 +90,7 @@ dependencies = [
 
 [[package]]
 name = "cc"
-version = "1.0.38"
+version = "1.0.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -104,7 +104,7 @@ version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "gleam 0.6.19 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -196,7 +196,7 @@ dependencies = [
  "core-foundation 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "core-graphics 0.17.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "foreign-types 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "objc 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -211,7 +211,7 @@ version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "core-foundation-sys 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -227,7 +227,7 @@ dependencies = [
  "bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "core-foundation 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "foreign-types 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -238,7 +238,7 @@ dependencies = [
  "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "core-foundation-sys 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "core-graphics 0.17.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "objc 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -305,7 +305,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.43 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -337,7 +337,7 @@ version = "1.0.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "crc32fast 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "miniz-sys 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "miniz_oxide_c_api 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -380,7 +380,7 @@ version = "0.1.8"
 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 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -531,7 +531,7 @@ name = "iovec"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -570,7 +570,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "libc"
-version = "0.2.60"
+version = "0.2.61"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -578,7 +578,7 @@ name = "libloading"
 version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "cc 1.0.38 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cc 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -616,7 +616,7 @@ name = "malloc_buf"
 version = "0.0.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -624,7 +624,7 @@ name = "memmap"
 version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -641,13 +641,13 @@ name = "miniz-sys"
 version = "0.1.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "cc 1.0.38 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cc 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "miniz_oxide"
-version = "0.3.1"
+version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "adler32 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -658,10 +658,10 @@ name = "miniz_oxide_c_api"
 version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "cc 1.0.38 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cc 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)",
  "crc32fast 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
- "miniz_oxide 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
+ "miniz_oxide 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -673,7 +673,7 @@ dependencies = [
  "fuchsia-zircon-sys 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "iovec 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "miow 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "net2 0.2.33 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -714,7 +714,7 @@ version = "0.2.33"
 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 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -724,9 +724,9 @@ version = "0.14.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "cc 1.0.38 (registry+https://github.com/rust-lang/crates.io-index)",
+ "cc 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)",
  "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -747,7 +747,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.43 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -792,7 +792,7 @@ name = "num_cpus"
 version = "1.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -836,7 +836,7 @@ 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)",
  "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -892,7 +892,7 @@ version = "0.6.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "autocfg 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -910,7 +910,7 @@ version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "getrandom 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_chacha 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_hc 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -984,7 +984,7 @@ name = "rand_jitter"
 version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -996,7 +996,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "fuchsia-cprng 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_core 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1065,7 +1065,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "rltk"
 version = "0.2.5"
-source = "git+https://github.com/thebracket/rltk_rs#998006df6ace9fb951312641cd8f32d815714be4"
+source = "git+https://github.com/thebracket/rltk_rs#882e3d3f45cd7b63b860b18fb3958d6d17f43304"
 dependencies = [
  "bresenham 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1145,7 +1145,7 @@ version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1215,7 +1215,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 0.6.13 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 0.15.43 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1228,7 +1228,7 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "0.15.43"
+version = "0.15.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1280,7 +1280,7 @@ dependencies = [
  "bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "calloop 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "downcast-rs 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "mio 0.6.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "nix 0.14.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "wayland-commons 0.23.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1379,7 +1379,7 @@ dependencies = [
  "derivative 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "dispatch 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "objc 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1405,7 +1405,7 @@ version = "2.18.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
  "pkg-config 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1433,7 +1433,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a7c3dd8985a7111efc5c80b44e23ecdd8c007de8ade3b96595387e812b957cf5"
 "checksum c2-chacha 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7d64d04786e0f528460fc884753cf8dddcc466be308f6026f8e355c41a0e4101"
 "checksum calloop 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)" = "7aa2097be53a00de9e8fc349fea6d76221f398f5c4fa550d420669906962d160"
-"checksum cc 1.0.38 (registry+https://github.com/rust-lang/crates.io-index)" = "ce400c638d48ee0e9ab75aef7997609ec57367ccfe1463f21bf53c3eca67bf46"
+"checksum cc 1.0.40 (registry+https://github.com/rust-lang/crates.io-index)" = "b548a4ee81fccb95919d4e22cfea83c7693ebfd78f0495493178db20b3139da7"
 "checksum cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)" = "b486ce3ccf7ffd79fdeb678eac06a9e6c09fc88d33836340becb8fffe87c5e33"
 "checksum cgl 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "55e7ec0b74fe5897894cbc207092c577e87c52f8a59e8ca8d97ef37551f60a49"
 "checksum cgmath 0.17.0 (registry+https://github.com/rust-lang/crates.io-index)" = "283944cdecc44bf0b8dd010ec9af888d3b4f142844fdbe026c20ef68148d6fe7"
@@ -1482,7 +1482,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum khronos_api 3.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2db585e1d738fc771bf08a151420d3ed193d9d895a36df7f6f8a9456b911ddc"
 "checksum lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bc5729f27f159ddd61f4df6228e827e86643d4d3e7c32183cb30a1c08f604a14"
 "checksum lazycell 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b294d6fa9ee409a054354afc4352b0b9ef7ca222c69b8812cbea9e7d2bf3783f"
-"checksum libc 0.2.60 (registry+https://github.com/rust-lang/crates.io-index)" = "d44e80633f007889c7eff624b709ab43c92d708caad982295768a7b13ca3b5eb"
+"checksum libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)" = "c665266eb592905e8503ba3403020f4b8794d26263f412ca33171600eca9a6fa"
 "checksum libloading 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f2b111a074963af1d37a139918ac6d49ad1d0d5e47f72fd55388619691a7d753"
 "checksum line_drawing 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5cc7ad3d82c845bdb5dde34ffdcc7a5fb4d2996e1e1ee0f19c33bc80e15196b9"
 "checksum lock_api 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ed946d4529956a20f2d63ebe1b69996d5a2137c91913fe3ebbeff957f5bca7ff"
@@ -1492,7 +1492,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum memmap 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "6585fd95e7bb50d6cc31e20d4cf9afb4e2ba16c5846fc76793f11218da9c475b"
 "checksum memoffset 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ce6075db033bbbb7ee5a0bbd3a3186bbae616f57fb001c485c7ff77955f8177f"
 "checksum miniz-sys 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)" = "1e9e3ae51cea1576ceba0dde3d484d30e6e5b86dee0b2d412fe3a16a15c98202"
-"checksum miniz_oxide 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "fe2959c5a0747a8d7a56b4444c252ffd2dda5d452cfd147cdfdda73b1c3ece5b"
+"checksum miniz_oxide 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7108aff85b876d06f22503dcce091e29f76733b2bfdd91eebce81f5e68203a10"
 "checksum miniz_oxide_c_api 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "6c675792957b0d19933816c4e1d56663c341dd9bfa31cb2140ff2267c1d8ecf4"
 "checksum mio 0.6.19 (registry+https://github.com/rust-lang/crates.io-index)" = "83f51996a3ed004ef184e16818edc51fadffe8e7ca68be67f9dee67d84d0ff23"
 "checksum mio-extras 2.0.5 (registry+https://github.com/rust-lang/crates.io-index)" = "46e73a04c2fa6250b8d802134d56d554a9ec2922bf977777c805ea5def61ce40"
@@ -1555,7 +1555,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum specs 0.15.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b98b8b33ab3f3e3f352df6cf6830e6d8fc790cbd6a7ff349c14fc25cbd6b1d48"
 "checksum specs-derive 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a63549fa0d4a6f76e99e6634c328f25d0c9fa8ad6f8498aef74f6c35c0b269e5"
 "checksum stb_truetype 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "69b7df505db8e81d54ff8be4693421e5b543e08214bd8d99eb761fcb4d5668ba"
-"checksum syn 0.15.43 (registry+https://github.com/rust-lang/crates.io-index)" = "ee06ea4b620ab59a2267c6b48be16244a3389f8bfa0986bdd15c35b890b00af3"
+"checksum syn 0.15.44 (registry+https://github.com/rust-lang/crates.io-index)" = "9ca4b3b69a77cbe1ffc9e198781b7acb0c7365a883670e8f1c1bc66fba79a5c5"
 "checksum tiff 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d7b7c2cfc4742bd8a32f2e614339dd8ce30dbcf676bb262bd63a2327bc5df57d"
 "checksum tuple_utils 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "44834418e2c5b16f47bedf35c28e148db099187dd5feee6367fb2525863af4f1"
 "checksum unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fc72304796d0818e357ead4e000d19c9c174ab23dc11093ac919054d20a6a7fc"

book/src/chapter_5.md

@@ -233,7 +233,7 @@ impl BaseMap for Map {
     fn get_pathing_distance(&self, idx1:i32, idx2:i32) -> f32 {
         let p1 = Point::new(idx1 % self.width, idx1 / self.width);
         let p2 = Point::new(idx2 % self.width, idx2 / self.width);
-        rltk::distance2d(rltk::DistanceAlg::Pythagoras, p1, p2)
+        rltk::DistanceAlg::Pythagoras.distance2d(p1, p2)
     }
 }
 ```

book/src/chapter_7.md

@@ -93,6 +93,215 @@ If you `cargo run` the project, monsters will now chase the player - and stop if
 
 # Blocking access
 
+We don't want monsters to walk on top of each other, nor do we want them to get stuck in a traffic jam hoping to find the player; we'd rather they are willing to try and flank the player! We'll accompany this by keeping track of what parts of the map are blocked.
+
+First, we'll add another vector of bools to our `Map`:
+
+```rust
+#[derive(Default)]
+pub struct Map {
+    pub tiles : Vec<TileType>,
+    pub rooms : Vec<Rect>,
+    pub width : i32,
+    pub height : i32,
+    pub revealed_tiles : Vec<bool>,
+    pub visible_tiles : Vec<bool>,
+    pub blocked : Vec<bool>
+}
+```
+
+We'll also initialize it, just like the other vectors:
+
+```rust
+let mut map = Map{
+    tiles : vec![TileType::Wall; 80*50],
+    rooms : Vec::new(),
+    width : 80,
+    height: 50,
+    revealed_tiles : vec![false; 80*50],
+    visible_tiles : vec![false; 80*50],
+    blocked : vec![false; 80*50]
+};
+```
+
+Lets introduce a new function to populate whether or not a tile is blocked. In the `Map` implementation:
+
+```rust
+pub fn populate_blocked(&mut self) {
+    for (i,tile) in self.tiles.iter_mut().enumerate() {
+        self.blocked[i] = *tile == TileType::Wall;
+    }
+}
+```
+
+This function is very simple: it sets `blocked` for a tile to true if its a wall, false otherwise (we'll expand it when we add more tile types). While we're working with `Map`, lets adjust `is_exit_valid` to use this data:
+
+```rust
+fn is_exit_valid(&self, x:i32, y:i32) -> bool {
+    if x < 1 || x > self.width-1 || y < 1 || y > self.height-1 { return false; }
+    let idx = (y * self.width) + x;
+    !self.blocked[idx as usize]
+}
+```
+
+Now we'll make a new component, `BlocksTile`. You should know the drill by now; in `Components.rs`:
+
+```rust
+#[derive(Component, Debug)]
+pub struct BlocksTile {}
+```rust
+
+Then register it in `main.rs`: `gs.ecs.register::<BlocksTile>();`
+
+We should apply `BlocksTile` to NPCs - so our NPC creation code becomes:
+
+```rust
+gs.ecs.create_entity()
+    .with(Position{ x, y })
+    .with(Renderable{
+        glyph,
+        fg: RGB::named(rltk::RED),
+        bg: RGB::named(rltk::BLACK),
+    })
+    .with(Viewshed{ visible_tiles : Vec::new(), range: 8, dirty: true })
+    .with(Monster{})
+    .with(Name{ name: format!("{} #{}", &name, i) })
+    .with(BlocksTile{})
+    .build();
+```
+
+Lastly, we need to populate the blocked list. We'll probably extend this system later, so we'll go with a nice generic name `map_indexing_system.rs`:
+
+```rust
+extern crate specs;
+use specs::prelude::*;
+use super::{Map, Position, BlocksTile};
+
+pub struct MapIndexingSystem {}
+
+impl<'a> System<'a> for MapIndexingSystem {
+    type SystemData = ( WriteExpect<'a, Map>,
+                        ReadStorage<'a, Position>,
+                        ReadStorage<'a, BlocksTile>);
+
+    fn run(&mut self, data : Self::SystemData) {
+        let (mut map, position, blockers) = data;
+
+        map.populate_blocked();
+        for (position, _blocks) in (&position, &blockers).join() {
+            let idx = map.xy_idx(position.x, position.y);
+            map.blocked[idx] = true;
+        }
+    }
+}
+```
+
+This tells the map to setup blocking from the terrain, and then iterates all entities with a `BlocksTile` component, and applies them to the blocked list. We need to register it with the dispatcher; in `main.rs`:
+
+```rust
+let mut gs = State {
+    ecs: World::new(),
+    systems : DispatcherBuilder::new()
+        .with(MapIndexingSystem{}, "map_indexing_system", &[])
+        .with(VisibilitySystem{}, "visibility_system", &[])
+        .with(MonsterAI{}, "monster_ai", &["visibility_system", "map_indexing_system"])
+        .build(),
+    runstate : RunState::Running
+};
+```
+
+We didn't specify any dependencies, we're relying upon Specs to figure out if it can run concurrently with anything. We do however add it to the dependency list for `MonsterAI` - the AI relies on its results, so it has to be done.
+
+If you `cargo run` now, monsters no longer end up on top of each other - but they do end up on top of the player. We should fix that. We can make the monster only yell when it is adjacent to the player. In `monster_ai_system.rs`, add this above the visibility test:
+
+```rust
+let distance = rltk::DistanceAlg::Pythagoras.distance2d(Point::new(pos.x, pos.y), *player_pos);
+if distance < 1.5 {
+    // Attack goes here
+    println!("{} shouts insults", name.name);
+    return;
+}
+```
+
+Lastly, we want to stop the player from walking over monsters. In `player.rs`, we replace the `if` statement that looks for walls with:
+
+```rust
+if !map.blocked[destination_idx] {
+```
+
+Since we already put walls into the blocked list, this should take care of the issue for now. `cargo run` shows that monsters now block the player. They block them *perfectly* - so a monster that wants to be in your way is an unpassable obstacle!
+
+# Allowing Diagonal Movement
+
+It would be nice to be able to bypass the monsters - and diagonal movement is a mainstay of roguelikes. So lets go ahead and support it. In `map.rs`'s `get_available_exits` function, we add them:
+
+```rust
+fn get_available_exits(&self, idx:i32) -> Vec<(i32, f32)> {
+    let mut exits : Vec<(i32, f32)> = Vec::new();
+    let x = idx % self.width;
+    let y = idx / self.width;
+
+    // Cardinal directions
+    if self.is_exit_valid(x-1, y) { exits.push((idx-1, 1.0)) };
+    if self.is_exit_valid(x+1, y) { exits.push((idx+1, 1.0)) };
+    if self.is_exit_valid(x, y-1) { exits.push((idx-self.width, 1.0)) };
+    if self.is_exit_valid(x, y+1) { exits.push((idx+self.width, 1.0)) };
+
+    // Diagonals
+    if self.is_exit_valid(x-1, y-1) { exits.push(((idx-self.width)-1, 1.45)); }
+    if self.is_exit_valid(x+1, y-1) { exits.push(((idx-self.width)+1, 1.45)); }
+    if self.is_exit_valid(x-1, y+1) { exits.push(((idx+self.width)-1, 1.45)); }
+    if self.is_exit_valid(x+1, y+1) { exits.push(((idx+self.width)+1, 1.45)); }
+
+    exits
+}
+```
+
+We also modify the `player.rs` input code:
+
+```rust
+pub fn player_input(gs: &mut State, ctx: &mut Rltk) -> RunState {
+    // Player movement
+    match ctx.key {
+        None => { return RunState::Paused } // Nothing happened
+        Some(key) => match key {
+            VirtualKeyCode::Left => try_move_player(-1, 0, &mut gs.ecs),
+            VirtualKeyCode::Numpad4 => try_move_player(-1, 0, &mut gs.ecs),
+            VirtualKeyCode::H => try_move_player(-1, 0, &mut gs.ecs),
+
+            VirtualKeyCode::Right => try_move_player(1, 0, &mut gs.ecs),
+            VirtualKeyCode::Numpad6 => try_move_player(1, 0, &mut gs.ecs),            
+            VirtualKeyCode::L => try_move_player(1, 0, &mut gs.ecs),
+
+            VirtualKeyCode::Up => try_move_player(0, -1, &mut gs.ecs),
+            VirtualKeyCode::Numpad8 => try_move_player(0, -1, &mut gs.ecs),
+            VirtualKeyCode::K => try_move_player(0, -1, &mut gs.ecs),
+
+            VirtualKeyCode::Down => try_move_player(0, 1, &mut gs.ecs),
+            VirtualKeyCode::Numpad2 => try_move_player(0, 1, &mut gs.ecs),
+            VirtualKeyCode::J => try_move_player(0, 1, &mut gs.ecs),
+
+            // Diagonals
+            VirtualKeyCode::Numpad9 => try_move_player(1, -1, &mut gs.ecs),
+            VirtualKeyCode::Y => try_move_player(1, -1, &mut gs.ecs),
+
+            VirtualKeyCode::Numpad7 => try_move_player(-1, -1, &mut gs.ecs),
+            VirtualKeyCode::U => try_move_player(-1, -1, &mut gs.ecs),
+
+            VirtualKeyCode::Numpad3 => try_move_player(1, 1, &mut gs.ecs),
+            VirtualKeyCode::N => try_move_player(1, 1, &mut gs.ecs),
+
+            VirtualKeyCode::Numpad1 => try_move_player(-1, 1, &mut gs.ecs),
+            VirtualKeyCode::B => try_move_player(-1, 1, &mut gs.ecs),
+
+            _ => { return RunState::Paused }
+        },
+    }
+    RunState::Running
+}
+```
+
+You can now diagonally dodge around monsters - and they can move/attack diagonally.
 
 ---
 

chapter-07-damage/src/components.rs

@@ -34,3 +34,6 @@ pub struct Monster {}
 pub struct Name {
     pub name : String
 }
+
+#[derive(Component, Debug)]
+pub struct BlocksTile {}

chapter-07-damage/src/main.rs

@@ -16,6 +16,8 @@ mod visibility_system;
 use visibility_system::VisibilitySystem;
 mod monster_ai_system;
 use monster_ai_system::MonsterAI;
+mod map_indexing_system;
+use map_indexing_system::MapIndexingSystem;
 
 #[derive(PartialEq, Copy, Clone)]
 pub enum RunState { Paused, Running }
@@ -55,8 +57,9 @@ fn main() {
     let mut gs = State {
         ecs: World::new(),
         systems : DispatcherBuilder::new()
+            .with(MapIndexingSystem{}, "map_indexing_system", &[])
             .with(VisibilitySystem{}, "visibility_system", &[])
-            .with(MonsterAI{}, "monster_ai", &["visibility_system"])
+            .with(MonsterAI{}, "monster_ai", &["visibility_system", "map_indexing_system"])
             .build(),
         runstate : RunState::Running
     };
@@ -66,6 +69,7 @@ fn main() {
     gs.ecs.register::<Viewshed>();
     gs.ecs.register::<Monster>();
     gs.ecs.register::<Name>();
+    gs.ecs.register::<BlocksTile>();
 
     let map : Map = Map::new_map_rooms_and_corridors();
     let (player_x, player_y) = map.rooms[0].center();
@@ -105,6 +109,7 @@ fn main() {
             .with(Viewshed{ visible_tiles : Vec::new(), range: 8, dirty: true })
             .with(Monster{})
             .with(Name{ name: format!("{} #{}", &name, i) })
+            .with(BlocksTile{})
             .build();
     }
 

chapter-07-damage/src/map.rs

@@ -17,7 +17,8 @@ pub struct Map {
     pub width : i32,
     pub height : i32,
     pub revealed_tiles : Vec<bool>,
-    pub visible_tiles : Vec<bool>
+    pub visible_tiles : Vec<bool>,
+    pub blocked : Vec<bool>
 }
 
 impl Map {
@@ -55,7 +56,13 @@ impl Map {
     fn is_exit_valid(&self, x:i32, y:i32) -> bool {
         if x < 1 || x > self.width-1 || y < 1 || y > self.height-1 { return false; }
         let idx = (y * self.width) + x;
-        self.tiles[idx as usize] != TileType::Wall
+        !self.blocked[idx as usize]
+    }
+
+    pub fn populate_blocked(&mut self) {        
+        for (i,tile) in self.tiles.iter_mut().enumerate() {
+            self.blocked[i] = *tile == TileType::Wall;
+        }
     }
 
     /// Makes a new map using the algorithm from http://rogueliketutorials.com/tutorials/tcod/part-3/
@@ -67,7 +74,8 @@ impl Map {
             width : 80,
             height: 50,
             revealed_tiles : vec![false; 80*50],
-            visible_tiles : vec![false; 80*50]
+            visible_tiles : vec![false; 80*50],
+            blocked : vec![false; 80*50]
         };
 
         const MAX_ROOMS : i32 = 30;
@@ -125,13 +133,19 @@ impl BaseMap for Map {
         if self.is_exit_valid(x, y-1) { exits.push((idx-self.width, 1.0)) };
         if self.is_exit_valid(x, y+1) { exits.push((idx+self.width, 1.0)) };
 
+        // Diagonals
+        if self.is_exit_valid(x-1, y-1) { exits.push(((idx-self.width)-1, 1.45)); }
+        if self.is_exit_valid(x+1, y-1) { exits.push(((idx-self.width)+1, 1.45)); }
+        if self.is_exit_valid(x-1, y+1) { exits.push(((idx+self.width)-1, 1.45)); }
+        if self.is_exit_valid(x+1, y+1) { exits.push(((idx+self.width)+1, 1.45)); }
+
         exits
     }
 
     fn get_pathing_distance(&self, idx1:i32, idx2:i32) -> f32 {
         let p1 = Point::new(idx1 % self.width, idx1 / self.width);
         let p2 = Point::new(idx2 % self.width, idx2 / self.width);
-        rltk::distance2d(rltk::DistanceAlg::Pythagoras, p1, p2)
+        rltk::DistanceAlg::Pythagoras.distance2d(p1, p2)
     }
 }
 

chapter-07-damage/src/map_indexing_system.rs

@@ -0,0 +1,21 @@
+extern crate specs;
+use specs::prelude::*;
+use super::{Map, Position, BlocksTile};
+
+pub struct MapIndexingSystem {}
+
+impl<'a> System<'a> for MapIndexingSystem {
+    type SystemData = ( WriteExpect<'a, Map>,
+                        ReadStorage<'a, Position>,
+                        ReadStorage<'a, BlocksTile>);
+
+    fn run(&mut self, data : Self::SystemData) {
+        let (mut map, position, blockers) = data;
+
+        map.populate_blocked();
+        for (position, _blocks) in (&position, &blockers).join() {
+            let idx = map.xy_idx(position.x, position.y);
+            map.blocked[idx] = true;
+        }
+    }
+}

chapter-07-damage/src/monster_ai_system.rs

@@ -19,16 +19,27 @@ impl<'a> System<'a> for MonsterAI {
         let (mut map, player_pos, mut viewshed, monster, name, mut position) = data;
 
         for (mut viewshed,_monster,name,mut pos) in (&mut viewshed, &monster, &name, &mut position).join() {
-            if viewshed.visible_tiles.contains(&*player_pos) {
+            let distance = rltk::DistanceAlg::Pythagoras.distance2d(Point::new(pos.x, pos.y), *player_pos);
+            if distance < 1.5 {
+                // Attack goes here
                 println!("{} shouts insults", name.name);
+                return;
+            }
+
+            if viewshed.visible_tiles.contains(&*player_pos) {
+                // Path to the player
                 let path = rltk::a_star_search(
                     map.xy_idx(pos.x, pos.y) as i32, 
                     map.xy_idx(player_pos.x, player_pos.y) as i32, 
                     &mut *map
                 );
                 if path.success && path.steps.len()>1 {
+                    let mut idx = map.xy_idx(pos.x, pos.y);
+                    map.blocked[idx] = false;
                     pos.x = path.steps[1] % map.width;
                     pos.y = path.steps[1] / map.width;
+                    idx = map.xy_idx(pos.x, pos.y);
+                    map.blocked[idx] = true;
                     viewshed.dirty = true;
                 }
             }

chapter-07-damage/src/player.rs

@@ -2,7 +2,7 @@ extern crate rltk;
 use rltk::{VirtualKeyCode, Rltk, Point};
 extern crate specs;
 use specs::prelude::*;
-use super::{Position, Player, Viewshed, TileType, State, Map, RunState};
+use super::{Position, Player, Viewshed, State, Map, RunState};
 
 pub fn try_move_player(delta_x: i32, delta_y: i32, ecs: &mut World) {
     let mut positions = ecs.write_storage::<Position>();
@@ -12,7 +12,7 @@ pub fn try_move_player(delta_x: i32, delta_y: i32, ecs: &mut World) {
 
     for (_player, pos, viewshed) in (&mut players, &mut positions, &mut viewsheds).join() {
         let destination_idx = map.xy_idx(pos.x + delta_x, pos.y + delta_y);
-        if map.tiles[destination_idx] != TileType::Wall {
+        if !map.blocked[destination_idx] {
             pos.x += delta_x;
             pos.y += delta_y;
 
@@ -37,15 +37,32 @@ pub fn player_input(gs: &mut State, ctx: &mut Rltk) -> RunState {
             VirtualKeyCode::Left => try_move_player(-1, 0, &mut gs.ecs),
             VirtualKeyCode::Numpad4 => try_move_player(-1, 0, &mut gs.ecs),
             VirtualKeyCode::H => try_move_player(-1, 0, &mut gs.ecs),
+
             VirtualKeyCode::Right => try_move_player(1, 0, &mut gs.ecs),
-            VirtualKeyCode::Numpad6 => try_move_player(1, 0, &mut gs.ecs),
+            VirtualKeyCode::Numpad6 => try_move_player(1, 0, &mut gs.ecs),            
             VirtualKeyCode::L => try_move_player(1, 0, &mut gs.ecs),
+
             VirtualKeyCode::Up => try_move_player(0, -1, &mut gs.ecs),
             VirtualKeyCode::Numpad8 => try_move_player(0, -1, &mut gs.ecs),
             VirtualKeyCode::K => try_move_player(0, -1, &mut gs.ecs),
+
             VirtualKeyCode::Down => try_move_player(0, 1, &mut gs.ecs),
             VirtualKeyCode::Numpad2 => try_move_player(0, 1, &mut gs.ecs),
             VirtualKeyCode::J => try_move_player(0, 1, &mut gs.ecs),
+
+            // Diagonals
+            VirtualKeyCode::Numpad9 => try_move_player(1, -1, &mut gs.ecs),
+            VirtualKeyCode::Y => try_move_player(1, -1, &mut gs.ecs),
+
+            VirtualKeyCode::Numpad7 => try_move_player(-1, -1, &mut gs.ecs),
+            VirtualKeyCode::U => try_move_player(-1, -1, &mut gs.ecs),
+
+            VirtualKeyCode::Numpad3 => try_move_player(1, 1, &mut gs.ecs),
+            VirtualKeyCode::N => try_move_player(1, 1, &mut gs.ecs),
+
+            VirtualKeyCode::Numpad1 => try_move_player(-1, 1, &mut gs.ecs),
+            VirtualKeyCode::B => try_move_player(-1, 1, &mut gs.ecs),
+
             _ => { return RunState::Paused }
         },
     }