add an option to specify the location of the camera; fixes #17

Author: Jakub Hlusička

scenes/4d_room.json

@@ -1,7 +1,16 @@
 {
   "Universe4": {
     "camera": {
-      "FreeCamera4": []
+      "FreeCamera4::new_with_location": [
+        {
+          "Point4": [
+            -10,
+            0,
+            0,
+            0
+          ]
+        }
+      ]
     },
     "entities": [
       {

src/scene.rs

@@ -1329,22 +1329,34 @@ impl Parser {
                 }
             }
 
-            // TODO: Add optional parameters via `Option<$($item_type:tt)+>`
             add_deserializer! {
                 "PitchYawCamera3", "PitchYawCamera3::new";
                 -> Box<Camera3<F>> {
                     Box::new(PitchYawCamera3::new())
                 }
             }
 
-            // TODO: Add optional parameters via `Option<$($item_type:tt)+>`
+            add_deserializer! {
+                "PitchYawCamera3::new_with_location";
+                [location: Point3<F>] -> Box<Camera3<F>> {
+                    Box::new(PitchYawCamera3::new_with_location(location))
+                }
+            }
+
             add_deserializer! {
                 "FreeCamera3", "FreeCamera3::new";
                 -> Box<Camera3<F>> {
                     Box::new(FreeCamera3::new())
                 }
             }
 
+            add_deserializer! {
+                "FreeCamera3::new_with_location";
+                [location: Point3<F>] -> Box<Camera3<F>> {
+                    Box::new(FreeCamera3::new_with_location(location))
+                }
+            }
+
             add_deserializer! {
                 "Universe4", "Universe4::new";
                 [camera: Box<Camera4<F>>]
@@ -1360,13 +1372,19 @@ impl Parser {
                 }
             }
 
-            // TODO: Add optional parameters via `Option<$($item_type:tt)+>`
             add_deserializer! {
                 "FreeCamera4", "FreeCamera4::new";
                 -> Box<Camera4<F>> {
                     Box::new(FreeCamera4::new())
                 }
             }
+
+            add_deserializer! {
+                "FreeCamera4::new_with_location";
+                [location: Point4<F>] -> Box<Camera4<F>> {
+                    Box::new(FreeCamera4::new_with_location(location))
+                }
+            }
         }
 
         parser

src/universe/d3/entity/camera.rs

@@ -42,6 +42,13 @@ impl<F: CustomFloat> Camera3Data<F> {
         }
     }
 
+    pub fn new_with_location(location: Point3<F>) -> Self {
+        Camera3Data {
+            location: location,
+            .. Self::new()
+        }
+    }
+
     fn get_left(&self) -> Vector3<F> {
         na::cross(&self.up, &self.forward).normalize()
     }
@@ -65,6 +72,12 @@ impl<F: CustomFloat> PitchYawCamera3<F> {
         }
     }
 
+    pub fn new_with_location(location: Point3<F>) -> Self {
+        PitchYawCamera3 {
+            data: Camera3Data::new_with_location(location)
+        }
+    }
+
     fn update_rotation(&mut self, context: &SimulationContext) {
         let delta_mouse_float: Vector2<F> =
             Vector2::new(<F as NumCast>::from(context.delta_mouse.x).unwrap(),
@@ -266,6 +279,12 @@ impl<F: CustomFloat> FreeCamera3<F> {
         }
     }
 
+    pub fn new_with_location(location: Point3<F>) -> Self {
+        FreeCamera3 {
+            data: Camera3Data::new_with_location(location)
+        }
+    }
+
     fn update_rotation(&mut self, delta_millis: F, context: &SimulationContext) {
         let delta_mouse_float: Vector2<F> =
             Vector2::new(<F as NumCast>::from(context.delta_mouse.x).unwrap(),

src/universe/d4/entity/camera.rs

@@ -48,6 +48,13 @@ impl<F: CustomFloat> FreeCamera4<F> {
         }
     }
 
+    pub fn new_with_location(location: Point4<F>) -> Self {
+        FreeCamera4 {
+            location: location,
+            .. Self::new()
+        }
+    }
+
     fn update_rotation(&mut self, delta_millis: F, context: &SimulationContext) {
         let pressed_keys: &HashSet<VirtualKeyCode> = context.pressed_keys();
         let mut angle: F = <F as Zero>::zero();