Include statements

[wahn]

The general structure of PBRT scene files allow Include statements (like this):

> rg Include
straight-hair.pbrt
20:	Include "models/straight-hair.pbrt" 

curly-hair.pbrt
15:	Include "models/curly-hair.pbrt" 

sphere-hairblock.pbrt
19:  Include "models/block.pbrt"

Currently we do not support those. Let's change that ...

[wahn]

After commit 5789abb a re-write of the parser works with Include statements:

> ./target/release/examples/parse_pbrt_file -i ../../../Graphics/Rendering/PBRT/pbrt-v3-scenes/bunny-fur/f3-15_no_exrs.pbrt
pbrt version 0.5.1 [Detected 8 cores]
Copyright (c) 2016-2019 Jan Douglas Bert Walter.
Rust code based on C++ code by Matt Pharr, Greg Humphreys, and Wenzel Jakob.
Film "image"
  "string filename" ["f3-15.exr"]
  "integer xresolution" [1200]
  "integer yresolution" [1200]
Sampler "sobol"
  "integer pixelsamples" [2048]
Sampler "sobol"
  "integer pixelsamples" [512]
Integrator "path"
  "integer maxdepth" [3]
Number of comment line(s):   0
Number of parameter line(s): 0
Number of empty line(s):     0
BVHAccel::recursive_build(..., 12138773, ...)
PT77.351456162S seconds for building BVH ...
BVHAccel::flatten_bvh_tree(...)
PT0.476367198S seconds for flattening BVH ...
Rendering with 8 thread(s) ...
5625 / 5625 [========================================================================] 100.00 % 0.64/s  
Writing image "pbrt.png" with bounds Bounds2 { p_min: Point2 { x: 0, y: 0 }, p_max: Point2 { x: 1200, y: 1200 } }
Number of comment line(s):   1
Number of parameter line(s): 5
Number of empty line(s):     9

The test scene contains a single Include statement:

> pwd
/mill3d/users/jan/Graphics/Rendering/PBRT/pbrt-v3-scenes/bunny-fur
> grep Include f3-15_no_exrs.pbrt
Include "geometry/bunnyfur.pbrt"

The test scene itself contains only 36 lines, but the included file contains 1.5 million lines:

> wc -l f3-15_no_exrs.pbrt
36 f3-15_no_exrs.pbrt
> wc -l geometry/bunnyfur.pbrt
1508665 geometry/bunnyfur.pbrt