Use camera settings from pbrt file

ray-tracing-core/src/affine_transform.rs

@@ -40,6 +40,10 @@ impl AffineTransform {
         Some(Self { mat, inv })
     }
 
+    pub fn get(&self, i: usize, j: usize) -> Float {
+        self.mat[j][i]
+    }
+
     pub fn identity() -> Self {
         Self {
             mat: [
@@ -127,7 +131,7 @@ impl AffineTransform {
     pub fn look_at(pos: Pos3, look: Pos3, up: Dir3) -> Option<Self> {
         let dir = (look - pos).normalize();
         let right = Dir3::cross(up.normalize(), dir).normalize();
-        let new_up = Dir3::cross(dir, right);
+        let new_up = Dir3::cross(right, dir);
 
         let mat = [
             [right.x(), new_up.x(), dir.x(), pos.x()],

ray-tracing-core/src/camera.rs

@@ -1,4 +1,4 @@
-use crate::prelude::*;
+use crate::{affine_transform::AffineTransform, prelude::*};
 
 pub trait Camera<R: Rng> {
     fn forward(&self, x: u32, y: u32, rng: &mut R) -> Ray;
@@ -41,6 +41,25 @@ impl BasicCamera {
         }
     }
 
+    pub fn from_affine_transform(
+        width: u32,
+        height: u32,
+        tm: AffineTransform,
+        horizontal_fov: Float,
+    ) -> Self {
+        assert!(horizontal_fov < FloatConsts::PI);
+
+        let l = Float::sin(0.5 * horizontal_fov);
+
+        Self {
+            width,
+            height,
+            pos: Pos3::new(tm.get(3, 0), tm.get(3, 1), tm.get(3, 2)),
+            dir: Dir3::new(tm.get(2, 0), tm.get(2, 1), tm.get(2, 2)),
+            h: l * Dir3::new(tm.get(0, 0), tm.get(0, 1), tm.get(0, 2)),
+            v: l * Dir3::new(tm.get(1, 0), tm.get(1, 1), tm.get(1, 2)),
+        }
+    }
     pub fn from_look_at(
         width: u32,
         height: u32,

ray-tracing-pbrt-scene/src/lib.rs

@@ -46,7 +46,7 @@ impl Lexer {
 
 #[derive(Debug)]
 #[allow(dead_code)]
-enum CameraType {
+pub enum CameraType {
     Orthographic {
         frame_aspect_ratio: Option<Float>,
         screen_window: Option<Float>,
@@ -64,8 +64,8 @@ enum CameraType {
 
 #[derive(Debug)]
 #[allow(dead_code)]
-struct PbrtCamera {
-    camera_type: CameraType,
+pub struct PbrtCamera {
+    pub camera_type: CameraType,
     shutter_open: Float,
     shutter_close: Float,
 }
@@ -640,10 +640,9 @@ impl<R: Rng> Pbrt<R> {
 }
 
 #[derive(Debug)]
-#[allow(dead_code)]
 pub struct PbrtWorldSettings {
-    camera: PbrtCamera,
-    camera_ctm: AffineTransform,
+    pub camera: PbrtCamera,
+    pub camera_ctm: AffineTransform,
 }
 
 #[derive(Debug)]
@@ -790,7 +789,7 @@ fn inner_parse_pbrt<R: Rng + std::fmt::Debug>(
                 *context.ctm.last_mut().unwrap() = affine_transform
             }
             Statement::Shape(shape_type, shape_alpha) => {
-                dbg!(&context);
+                // dbg!(&context);
                 if context.area_light.is_empty() {
                     pbrt.scene.shapes.push(Shape {
                         ctm: context.get_ctm(),

ray-tracing-tev/src/main.rs

@@ -7,7 +7,7 @@ use ray_tracing_core::{
     renderer::ClassicalRenderer,
     scene::Scene,
 };
-use ray_tracing_pbrt_scene::parse_pbrt_v4;
+use ray_tracing_pbrt_scene::{parse_pbrt_v4, CameraType};
 use ray_tracing_renderer::{
     depth_renderer::DepthRenderer, mis::MIS, next_event_estimation::NextEventEstimation,
     path_tracer::PathTracer, path_tracer_importance::PathTracerImportance,
@@ -230,15 +230,29 @@ fn main() {
             }
         };
 
-        let c = BasicCamera::from_look_at(
+        let fov = match pbrt.settings.camera.camera_type {
+            CameraType::Perspective { fov, .. } => 2.0 * fov,
+            _ => todo!(),
+        };
+
+        let c = BasicCamera::from_affine_transform(
             args.width,
             args.height,
-            Pos3::new(3.0, 4.0, 1.5),
-            Pos3::new(0.5, 0.5, 0.0),
-            Dir3::new(0.0, 0.0, 1.0),
-            Float::to_radians(90.0),
+            pbrt.settings.camera_ctm,
+            Float::to_radians(fov),
         );
 
+        // let c = BasicCamera::from_look_at(
+        //     args.width,
+        //     args.height,
+        //     Pos3::new(-0.3, 0.5, -0.5),
+        //     Pos3::new(0.0, 0.75, 0.0),
+        //     Dir3::new(0.0, 1.0, 0.0),
+        //     Float::to_radians(2.0 * 37.0),
+        // );
+
+        // dbg!(c);
+
         let s = &pbrt.scene;
 
         choose_renderer(