feat(rt_interp): enable file locations for include

lispers-core/src/lisp/environment.rs

@@ -1,5 +1,5 @@
 use super::{expression::Expression, prelude::mk_prelude};
-use std::{cell::RefCell, collections::HashMap, rc::Rc};
+use std::{cell::RefCell, collections::HashMap, env, path::Path, rc::Rc};
 
 #[derive(PartialEq, Clone, Debug)]
 /// A Environment is a stack of `EnvironmentLayer`s. Each `EnvironmentLayer` is a mapping from

lispers-core/src/lisp/eval.rs

@@ -19,6 +19,12 @@ pub enum EvalError {
     ParserError(ParserError),
 }
 
+impl From<ParserError> for EvalError {
+    fn from(value: ParserError) -> Self {
+        EvalError::ParserError(value)
+    }
+}
+
 impl Display for EvalError {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
         match self {

lispers-core/src/lisp/expression.rs

@@ -361,7 +361,7 @@ impl Display for Expression {
             Expression::Symbol(s) => write!(f, "{}", s),
             Expression::Integer(i) => write!(f, "{}", i),
             Expression::Float(fl) => write!(f, "{}", fl),
-            Expression::String(s) => write!(f, "{}", s),
+            Expression::String(s) => write!(f, "\"{}\"", s),
             Expression::True => write!(f, "true"),
             Expression::Nil => write!(f, "nil"),
         }

lispers-core/src/lisp/prelude.rs

@@ -1,3 +1,6 @@
+use crate::parser::ExpressionStream;
+use crate::parser::ParserError;
+
 use super::environment::Environment;
 use super::environment::EnvironmentLayer;
 use super::eval::eval;
@@ -5,6 +8,7 @@ use super::eval::CellIterator;
 use super::eval::EvalError;
 use super::expression::Expression;
 use std::collections::HashMap;
+use std::path::PathBuf;
 
 pub fn prelude_add(env: &Environment, expr: Expression) -> Result<Expression, EvalError> {
     let [a, b] = expr.try_into()?;
@@ -325,6 +329,54 @@ pub fn prelude_to_string(env: &Environment, expr: Expression) -> Result<Expressi
     Ok(Expression::String(format!("{}", eval(env, e)?)))
 }
 
+pub fn prelude_load(env: &Environment, expr: Expression) -> Result<Expression, EvalError> {
+    let [expr] = expr.try_into()?;
+    let lisp_string: String = eval(env, expr)?.try_into()?;
+
+    let mut last_result = Expression::Nil;
+
+    for expr in ExpressionStream::from_char_stream(lisp_string.chars())
+        .collect::<Result<Vec<Expression>, ParserError>>()?
+    {
+        last_result = eval(env, expr)?;
+    }
+
+    Ok(last_result)
+}
+
+pub fn prelude_include(env: &Environment, expr: Expression) -> Result<Expression, EvalError> {
+    let [expr] = expr.try_into()?;
+    let lisp_file: String = eval(env, expr)?.try_into()?;
+
+    // Try to resolve as relative to FILE
+    let resolved_lisp_file: PathBuf = PathBuf::from(
+        env.get("FILE")
+            .map(|x| x.try_into())
+            .unwrap_or(Ok(String::new()))?,
+    )
+    .parent()
+    .ok_or(EvalError::RuntimeError(
+        "Could not get parent of current file.".to_string(),
+    ))?
+    .join(&lisp_file);
+
+    let lisp_string = std::fs::read_to_string(&resolved_lisp_file)
+        .map_err(|e| EvalError::RuntimeError(e.to_string()))?;
+
+    // Use enviroment for resolved file or fallback to the lisp_file argument
+    let mut env = env.mk_inner();
+    env.set(
+        "FILE".to_string(),
+        resolved_lisp_file
+            .to_str()
+            .unwrap_or(&lisp_file)
+            .to_string()
+            .into(),
+    );
+
+    prelude_load(&env, [lisp_string.into()].into())
+}
+
 pub fn mk_prelude(layer: &mut EnvironmentLayer) {
     layer.set("+".to_string(), Expression::Function(prelude_add));
     layer.set("-".to_string(), Expression::Function(prelude_sub));
@@ -355,4 +407,6 @@ pub fn mk_prelude(layer: &mut EnvironmentLayer) {
         "to-string".to_string(),
         Expression::Function(prelude_to_string),
     );
+    layer.set("load".to_string(), Expression::Function(prelude_load));
+    layer.set("include".to_string(), Expression::Function(prelude_include));
 }

scenes/demo-2.lisp

@@ -1,33 +1,4 @@
-(set 'red
-     (material
-      (color 1 0 0)
-      (color 1 0 0)
-      (color 0.5 0 0)
-      50 0.25))
-(set 'blue
-     (material
-      (color 0 0 1)
-      (color 0 0 1)
-      (color 0 0 0.6)
-      50 0.25))
-(set 'green
-     (material
-      (color 0 1 0)
-      (color 0 1 0)
-      (color 0 0.6 0)
-      50 0.25))
-(set 'white
-     (material
-      (color 1 1 1)
-      (color 1 1 1)
-      (color 0.6 0.6 0.6)
-      100 0.5))
-(set 'black
-     (material
-      (color 0 0 0)
-      (color 0 0 0)
-      (color 0.6 0.6 0.6)
-      100 0.5))
+(include "./materials.lisp")
 
 (set 's1
      (sphere
@@ -36,22 +7,26 @@
      (sphere
       (point 2 0.5 2) 0.5 green))
 
-(defun spiral-sphere (i n)
+(set 'mirror-dome
+     (sphere
+      (point 0 -30 0)
+      100 dark-mirror))
+
+(defun spiral-sphere (i n t)
   (sphere
    (progn
-     (print "Spiral Sphere at: ")
-     (println (point
-               (* 2 (cos (/ (* i 6.2) n)))
-               0.5
-               (* 2 (sin (/ (* i 6.2) n)))))
+     (point
+      (* 2 (cos (/ (* i 6.2) n)))
+      (+ 0.5 (* 0.3 (cos (+ (/ (* i 6.2) n) (/ t 5.0)))))
+      (* 2 (sin (/ (* i 6.2) n))))
      )
-   0.5 red))
+   0.2 red))
 
-(defun spiral (scn i n)
+(defun spiral (scn i n t)
   (if (< i n)
       (scene-add
-       (spiral scn (+ i 1) n)
-       (spiral-sphere i n))
+       (spiral scn (+ i 1) n t)
+       (spiral-sphere i n t))
       scn))
 
 (set 'p1
@@ -67,22 +42,20 @@
 
 (set 'scn-base (scene
                 (color 0.1 0.1 0.1)
-                '(s1 s2 p1)
+                '(s1 s2 p1 mirror-dome)
                 '(l1 l2)))
 
-(set 'scn (spiral scn-base 0 10))
-
 (set 'cam (camera (point 0 3 6) (point 0 0 0) (vector 0 1 0) 40 1920 1080))
 
 (defun scene-fn (t)
-  scn)
+  (spiral scn-base 0 30 t))
 
 (defun cam-fn (t c)
-  (let '((pos . (point 0 4 8))
+  (let '((pos . (point -3 0.5 8))
          (cnt . (point 0 0 0))
-         (to . (point -2 3 -6))
+         (to . (point -3 0.5 -8))
          (up . (vector 0 1 0))
-         (fovy . 40)
+         (fovy . 80)
          (pct . (/ t 300.0)))
     (let '((tpos . (vadd pos (vmul (vsub to pos) pct)))
            (tfovy . (+ fovy (* 40 pct)))
@@ -91,4 +64,4 @@
       )
     ))
 
-(render-animation cam "demo-animation-2.mp4" scene-fn cam-fn 300 30 4 2)
+(render-animation cam "demo-animation.mp4" scene-fn cam-fn 400 30 4 2)

src/bin/lisp_demo.rs

@@ -15,6 +15,8 @@ fn main() {
         "(defun do-n-times (f n) (if (= n 0) '() (cons (f) (do-n-times f (- n 1)))))",
         "(do-n-times (lambda () (print 'hello)) 5)",
         "(progn (print 'hello) (print 'world))",
+        "(load \"(defun loaded-foo (x) (+ x 1))\")",
+        "(loaded-foo 1)",
     ];
 
     let environment = Environment::default();

src/bin/rt_interp.rs

@@ -17,20 +17,27 @@ fn main() {
     mk_prelude(&mut layer);
     mk_raytrace(&mut layer);
 
-    let environment = Environment::from_layer(layer);
+    let mut environment = Environment::from_layer(layer);
 
-    for (i, r) in
-        ExpressionStream::from_char_stream(programs.iter().map(|p| p.chars()).flatten()).enumerate()
-    {
-        match r {
-            Err(err) => {
-                println!("ParserError in Expression {}: {:?}", i + 1, err);
-                break;
+    for (program, path) in programs.iter().zip(program_paths) {
+        environment.set("FILE".to_string(), path.clone().into());
+
+        for (i, r) in ExpressionStream::from_char_stream(program.chars()).enumerate() {
+            match r {
+                Err(err) => {
+                    println!(
+                        "ParserError in File {} Expression {}: {:?}",
+                        path,
+                        i + 1,
+                        err
+                    );
+                    break;
+                }
+                Ok(expr) => match eval(&environment, expr) {
+                    Ok(_) => {}
+                    Err(e) => println!("Error evaluating Expression {}: {}", i + 1, e),
+                },
             }
-            Ok(expr) => match eval(&environment, expr) {
-                Ok(_) => {}
-                Err(e) => println!("Error evaluating Expression {}: {}", i + 1, e),
-            },
         }
     }
 

src/raytracer/sphere.rs

@@ -1,3 +1,5 @@
+use nalgebra::distance;
+
 use super::types::{Intersect, Material, Point3, Ray, Scalar, Vector3};
 
 extern crate nalgebra as na;
@@ -52,12 +54,21 @@ impl Intersect for Sphere {
             if t < Scalar::MAX {
                 let isect_pt: Point3 = ray.origin + ray.direction * t;
 
-                return Some((
-                    isect_pt,
-                    (isect_pt - self.center) / self.radius,
-                    t,
-                    self.material.clone(),
-                ));
+                if c >= 0.0 {
+                    return Some((
+                        isect_pt,
+                        (isect_pt - self.center) / self.radius,
+                        t,
+                        self.material.clone(),
+                    ));
+                } else {
+                    return Some((
+                        isect_pt,
+                        -(isect_pt - self.center) / self.radius,
+                        t,
+                        self.material.clone(),
+                    ));
+                }
             }
         }