added rcamera functions into core::camera (#185)

* added rcamera functions into core::camera

* minor formatting

* formatting and docs

Author: Ben Young

raylib/src/core/camera.rs

@@ -1,9 +1,34 @@
 //! Utility code for using Raylib [`Camera3D`] and [`Camera2D`]
-use raylib_sys::CameraMode;
+use raylib_sys::{CameraMode, KeyboardKey, MouseButton, GamepadAxis};
+use raylib_sys::{RL_CULL_DISTANCE_NEAR, RL_CULL_DISTANCE_FAR, DEG2RAD};
 
-use crate::core::math::{Vector2, Vector3};
+use crate::core::math::{Vector2, Vector3, Quaternion, Matrix};
 use crate::core::RaylibHandle;
 use crate::ffi;
+pub use ffi::CameraProjection;
+
+const CAMERA_CULL_DISTANCE_NEAR: f64 = RL_CULL_DISTANCE_NEAR;
+const CAMERA_CULL_DISTANCE_FAR : f64 = RL_CULL_DISTANCE_FAR;
+
+const CAMERA_MOVE_SPEED     : f32 = 0.09;
+const CAMERA_ROTATION_SPEED : f32 = 0.03;
+const CAMERA_PAN_SPEED      : f32 = 0.2;
+
+// Camera mouse movement sensitivity
+const CAMERA_MOUSE_MOVE_SENSITIVITY  : f32 = 0.003;
+const CAMERA_MOUSE_SCROLL_SENSITIVITY: f32 = 1.5;
+
+// Radians per second
+const CAMERA_ORBITAL_SPEED: f32 = 0.5;       
+
+
+const CAMERA_FIRST_PERSON_STEP_TRIGONOMETRIC_DIVIDER: f32 =   8.0;
+const CAMERA_FIRST_PERSON_STEP_DIVIDER              : f32 =  30.0;
+const CAMERA_FIRST_PERSON_WAVING_DIVIDER            : f32 = 200.0;
+
+// PLAYER (used by camera)
+const PLAYER_MOVEMENT_SENSITIVITY: f32 = 20.0;
+
 
 /// Camera, defines position/orientation in 3d space
 #[repr(C)]
@@ -18,7 +43,7 @@ pub struct Camera3D {
     /// Camera field-of-view aperture in Y (degrees) in perspective, used as near plane width in orthographic
     pub fovy: f32,
     /// Camera projection: CAMERA_PERSPECTIVE or CAMERA_ORTHOGRAPHIC
-    projection_: ffi::CameraProjection,
+    pub projection: CameraProjection,
 }
 /// Camera type fallback, defaults to Camera3D
 pub type Camera = Camera3D;
@@ -42,7 +67,7 @@ impl Into<ffi::Camera3D> for &Camera3D {
             target: self.target.into(),
             up: self.up.into(),
             fovy: self.fovy,
-            projection: (self.projection_ as u32) as i32,
+            projection: (self.projection as u32) as i32,
         }
     }
 }
@@ -87,7 +112,7 @@ impl Into<ffi::Camera2D> for &Camera2D {
 impl Camera3D {
     /// Camera projection: CAMERA_PERSPECTIVE or CAMERA_ORTHOGRAPHIC
     pub const fn camera_type(&self) -> crate::consts::CameraProjection {
-        unsafe { std::mem::transmute_copy(&self.projection_) }
+        unsafe { std::mem::transmute_copy(&self.projection) }
     }
     /// Create a perspective camera.
     /// fovy is in degrees
@@ -97,16 +122,322 @@ impl Camera3D {
             target,
             up,
             fovy,
-            projection_: ffi::CameraProjection::CAMERA_PERSPECTIVE,
+            projection: CameraProjection::CAMERA_PERSPECTIVE,
         }
     }
     /// Create a orthographic camera.
     /// fovy is in degrees
     pub fn orthographic(position: Vector3, target: Vector3, up: Vector3, fovy: f32) -> Camera3D {
         let mut c = Self::perspective(position, target, up, fovy);
-        c.projection_ = ffi::CameraProjection::CAMERA_ORTHOGRAPHIC;
+        c.projection = CameraProjection::CAMERA_ORTHOGRAPHIC;
         c
     }
+    /// Returns the cameras forward vector (normalized)
+    pub fn get_forward(&self) -> Vector3 {
+        (self.target - self.position).normalized()
+    }
+
+    /// Returns the cameras up vector (normalized)
+    /// Note: The up vector might not be perpendicular to the forward vector
+    pub fn get_up(&self) -> Vector3 {
+        self.up.normalized()
+    }
+
+    /// Returns the cameras right vector (normalized)
+    pub fn get_right(&self) -> Vector3 {
+        let forward = self.get_forward();
+        let up = self.get_up();
+
+        forward.cross(up)
+    }
+
+    /// Moves the camera in its forward direction
+    pub fn move_forward(&mut self, distance: f32, move_in_world_plane: bool) {
+        let mut forward = self.get_forward();
+
+        if move_in_world_plane
+        {
+            // Project vector onto world plane
+            forward.y = 0.;
+            forward.normalize();
+        }
+
+        // Scale by distance
+        forward.scale(distance);
+
+        // Move position and target
+        self.position = self.position + forward;
+        self.target = self.target + forward;
+    }
+
+    /// Moves the camera in its up direction
+    pub fn move_up(&mut self, distance: f32) {
+        let mut up = self.get_up();
+
+        // Scale by distance
+        up.scale(distance);
+
+        // Move position and target
+        self.position = self.position + up;
+        self.target = self.target + up;
+    }
+
+    /// Moves the camera target in its current right direction
+    pub fn move_right(&mut self, distance: f32, move_in_world_plane: bool) {
+        let mut right = self.get_right();
+
+        if move_in_world_plane
+        {
+            // Project vector onto world plane
+            right.y = 0.;
+            right.normalize();
+        }
+
+        // Scale by distance
+        right.scale(distance);
+
+        // Move position and target
+        self.position = self.position + right;
+        self.target = self.target + right;
+    }
+
+    /// Moves the camera position closer/farther to/from the camera target
+    pub fn move_to_target(&mut self, delta: f32){
+        let mut distance = self.position.distance_to(self.target);
+
+        // Apply delta
+        distance += delta;
+
+        // Distance must be greater than 0
+        if distance <= 0. { distance = 0.001; }
+
+        // Set new distance by moving the position along the forward vector
+        let forward = self.get_forward();
+        self.position = self.target + forward.scale_by(distance);
+    }
+
+    /// Rotates the camera around its up vector
+    /// Yaw is "looking left and right"
+    /// If rotateAroundTarget is false, the camera rotates around its position
+    /// Note: angle must be provided in radians
+    pub fn set_yaw(&mut self, angle: f32, rotate_around_target: bool) {
+        // Rotation axis
+        let up = self.get_up();
+
+        // View vector
+        let target_position = self.target - self.position;
+
+        // Rotate view vector around up axis
+        let target_position = target_position.rotate_by(Quaternion::from_axis_angle(up, angle));
+
+        if rotate_around_target
+        {
+            // Move position relative to target
+            self.position = self.target - target_position;
+        }
+        else // rotate around camera.position
+        {
+            // Move target relative to position
+            self.target = self.position + target_position;
+        }
+    }
+
+    /// Rotates the camera around its right vector, pitch is "looking up and down"
+    ///  - lockView prevents camera overrotation (aka "somersaults")
+    ///  - rotateAroundTarget defines if rotation is around target or around its position
+    ///  - rotateUp rotates the up direction as well (typically only usefull in CAMERA_FREE)
+    /// NOTE: angle must be provided in radians
+    pub fn set_pitch(&mut self, mut angle: f32, lock_view: bool, rotate_around_target: bool, rotate_up: bool) {
+        // Up direction
+        let up = self.get_up();
+
+        // View vector
+        let mut target_position = self.target - self.position;
+
+        if lock_view {
+            // In these camera modes we clamp the Pitch angle
+            // to allow only viewing straight up or down.
+
+            // Clamp view up
+            let mut max_angle_up = up.angle_to(target_position);
+            max_angle_up -= 0.001; // avoid numerical errors
+            if angle > max_angle_up { angle = max_angle_up };
+
+            // Clamp view down
+            let mut max_angle_down = (-up).angle_to(target_position);
+            max_angle_down *= -1.; // downwards angle is negative
+            max_angle_down += 0.001; // avoid numerical errors
+            if angle < max_angle_down { angle = max_angle_down };
+        }
+
+        // Rotation axis
+        let right = self.get_right();
+
+        // Rotate view vector around right axis
+        target_position = target_position.rotate_by(Quaternion::from_axis_angle( right, angle));
+
+        if rotate_around_target
+        {
+            // Move position relative to target
+            self.position = self.target - target_position;
+        }
+        else // rotate around camera.position
+        {
+            // Move target relative to position
+            self.target = self.position + target_position;
+        }
+
+        if rotate_up
+        {
+            // Rotate up direction around right axis
+            self.up = self.up.rotate_by(Quaternion::from_axis_angle(right, angle));
+        }
+    }
+
+    /// Rotates the camera around its forward vector
+    /// Roll is "turning your head sideways to the left or right"
+    /// Note: angle must be provided in radians
+    pub fn set_roll(&mut self, angle: f32) {
+        // Rotation axis
+        let forward = self.get_forward();
+
+        // Rotate up direction around forward axis
+        self.up = self.up.rotate_by(Quaternion::from_axis_angle(forward, angle));
+    }
+
+    /// Returns the camera view matrix
+    pub fn get_view_matrix(&self) -> Matrix {
+        Matrix::look_at(self.position, self.target, self.up)
+    }
+
+    /// Returns the camera projection matrix
+    pub fn get_projection_matrix(&self, aspect: f32) -> Matrix {
+        if self.projection == CameraProjection::CAMERA_PERSPECTIVE
+        {
+            return Matrix::perspective(self.fovy * DEG2RAD as f32, aspect, CAMERA_CULL_DISTANCE_NEAR as f32, CAMERA_CULL_DISTANCE_FAR as f32);
+        }
+        else if self.projection == CameraProjection::CAMERA_ORTHOGRAPHIC
+        {
+            let top = self.fovy/2.0;
+            let right = top*aspect;
+
+            return Matrix::ortho(-right, right, -top, top, CAMERA_CULL_DISTANCE_NEAR as f32, CAMERA_CULL_DISTANCE_FAR as f32);
+        }
+
+        return Matrix::identity();
+    }
+
+    /// Update camera position for selected mode
+    /// Camera mode: CAMERA_FREE, CAMERA_FIRST_PERSON, CAMERA_THIRD_PERSON, CAMERA_ORBITAL or CUSTOM
+    pub fn update_camera(&mut self, rl: &mut RaylibHandle, mode: CameraMode) {
+        let mouse_position_delta = rl.get_mouse_delta();
+        
+        let move_in_world_plane = (mode == CameraMode::CAMERA_FIRST_PERSON) || (mode == CameraMode::CAMERA_THIRD_PERSON);
+        let rotate_around_target = (mode == CameraMode::CAMERA_THIRD_PERSON) || (mode == CameraMode::CAMERA_ORBITAL);
+        let lock_view = (mode == CameraMode::CAMERA_FIRST_PERSON) || (mode == CameraMode::CAMERA_THIRD_PERSON) || (mode == CameraMode::CAMERA_ORBITAL);
+        let rotate_up = false;
+
+        if mode == CameraMode::CAMERA_ORBITAL
+        {
+            // Orbital can just orbit
+            let rotation = Matrix::rotate(self.get_up(), CAMERA_ORBITAL_SPEED*rl.get_frame_time());
+            let mut view = self.position - self.target;
+            view.transform(rotation);
+            self.position = self.target + view;
+        }
+        else
+        {
+            // Camera rotation
+            if rl.is_key_down(KeyboardKey::KEY_DOWN) {self.set_pitch(-CAMERA_ROTATION_SPEED, lock_view, rotate_around_target, rotate_up); }
+            if rl.is_key_down(KeyboardKey::KEY_UP) {self.set_pitch(CAMERA_ROTATION_SPEED, lock_view, rotate_around_target, rotate_up);}
+            if rl.is_key_down(KeyboardKey::KEY_RIGHT) {self.set_yaw(-CAMERA_ROTATION_SPEED, rotate_around_target);}
+            if rl.is_key_down(KeyboardKey::KEY_LEFT) {self.set_yaw(CAMERA_ROTATION_SPEED, rotate_around_target);}
+            if rl.is_key_down(KeyboardKey::KEY_Q) {self.set_roll(-CAMERA_ROTATION_SPEED);}
+            if rl.is_key_down(KeyboardKey::KEY_E) {self.set_roll(CAMERA_ROTATION_SPEED);}
+
+            // Camera movement
+            if !rl.is_gamepad_available(0)
+            {
+                // Camera pan (for CAMERA_FREE)
+                if (mode == CameraMode::CAMERA_FREE) && (rl.is_mouse_button_down(MouseButton::MOUSE_BUTTON_MIDDLE))
+                {
+                    let mouse_delta = rl.get_mouse_delta();
+                    if mouse_delta.x > 0.0 { self.move_right(CAMERA_PAN_SPEED, move_in_world_plane);  }
+                    if mouse_delta.x < 0.0 { self.move_right(-CAMERA_PAN_SPEED, move_in_world_plane); }
+                    if mouse_delta.y > 0.0 { self.move_up(-CAMERA_PAN_SPEED);}
+                    if mouse_delta.y < 0.0 { self.move_up(CAMERA_PAN_SPEED);}
+                }
+                else
+                {
+                    // Mouse support
+                    self.set_yaw(-mouse_position_delta.x*CAMERA_MOUSE_MOVE_SENSITIVITY, rotate_around_target);
+                    self.set_pitch(-mouse_position_delta.y*CAMERA_MOUSE_MOVE_SENSITIVITY, lock_view, rotate_around_target, rotate_up);
+                }
+
+                // Keyboard support
+                if rl.is_key_down(KeyboardKey::KEY_W) { self.move_forward(CAMERA_MOVE_SPEED, move_in_world_plane);}
+                if rl.is_key_down(KeyboardKey::KEY_A) { self.move_right(-CAMERA_MOVE_SPEED, move_in_world_plane);}
+                if rl.is_key_down(KeyboardKey::KEY_S) { self.move_forward(-CAMERA_MOVE_SPEED, move_in_world_plane);}
+                if rl.is_key_down(KeyboardKey::KEY_D) { self.move_right(CAMERA_MOVE_SPEED, move_in_world_plane);    }
+            }
+            else
+            {
+                // Gamepad controller support
+                self.set_yaw(-(rl.get_gamepad_axis_movement(0, GamepadAxis::GAMEPAD_AXIS_RIGHT_X) * 2.)*CAMERA_MOUSE_MOVE_SENSITIVITY, rotate_around_target);
+                self.set_pitch(-(rl.get_gamepad_axis_movement(0, GamepadAxis::GAMEPAD_AXIS_RIGHT_Y) * 2.)*CAMERA_MOUSE_MOVE_SENSITIVITY, lock_view, rotate_around_target, rotate_up);
+
+                if rl.get_gamepad_axis_movement(0, GamepadAxis::GAMEPAD_AXIS_LEFT_Y) <= -0.25 { self.move_forward(CAMERA_MOVE_SPEED, move_in_world_plane);}
+                if rl.get_gamepad_axis_movement(0, GamepadAxis::GAMEPAD_AXIS_LEFT_X) <= -0.25 { self.move_right(-CAMERA_MOVE_SPEED, move_in_world_plane);}
+                if rl.get_gamepad_axis_movement(0, GamepadAxis::GAMEPAD_AXIS_LEFT_Y) >= 0.25  { self.move_forward(-CAMERA_MOVE_SPEED, move_in_world_plane);}
+                if rl.get_gamepad_axis_movement(0, GamepadAxis::GAMEPAD_AXIS_LEFT_X) >= 0.25  { self.move_right(CAMERA_MOVE_SPEED, move_in_world_plane);     }
+            }
+
+            if mode == CameraMode::CAMERA_FREE
+            {
+                if rl.is_key_down(KeyboardKey::KEY_SPACE) { self.move_up(CAMERA_MOVE_SPEED); }
+                if rl.is_key_down(KeyboardKey::KEY_LEFT_CONTROL) { self.move_up(-CAMERA_MOVE_SPEED); }
+            }
+        }
+
+        if (mode == CameraMode::CAMERA_THIRD_PERSON) || (mode == CameraMode::CAMERA_ORBITAL) || (mode == CameraMode::CAMERA_FREE)
+        {
+            // Zoom target distance
+            self.move_to_target(-rl.get_mouse_wheel_move());
+            if rl.is_key_pressed(KeyboardKey::KEY_KP_SUBTRACT) {self.move_to_target(2.0);}
+            if rl.is_key_pressed(KeyboardKey::KEY_KP_ADD) {self.move_to_target(-2.0); }
+        }
+    }
+
+    /// Update camera movement, movement/rotation values should be provided by user
+    pub fn update_camera_pro(&mut self, movement: Vector3, rotation: Vector3, zoom: f32) {
+        // Required values
+        // movement.x - Move forward/backward
+        // movement.y - Move right/left
+        // movement.z - Move up/down
+        // rotation.x - yaw
+        // rotation.y - pitch
+        // rotation.z - roll
+        // zoom - Move towards target
+
+        let lock_view = true;
+        let rotate_around_target = false;
+        let rotate_up = false;
+        let move_in_world_plane = true;
+
+        // Camera rotation
+        self.set_pitch(-rotation.y*DEG2RAD as f32, lock_view, rotate_around_target, rotate_up);
+        self.set_yaw(-rotation.x*DEG2RAD as f32, rotate_around_target);
+        self.set_roll(rotation.z*DEG2RAD as f32);
+
+        // Camera movement
+        self.move_forward(movement.x, move_in_world_plane);
+        self.move_right(movement.y, move_in_world_plane);
+        self.move_up(movement.z);
+
+        // Zoom target distance
+        self.move_to_target(zoom);
+    }
+
 }
 
 impl RaylibHandle {