Skip to content

INTERACTIVE.md

Latest commit

 

History

History
132 lines (94 loc) · 3.49 KB

INTERACTIVE.md

File metadata and controls

132 lines (94 loc) · 3.49 KB

Interactive Controls

Overview

miniRT provides real-time interactive controls for manipulating the scene. When running, press keys or use the mouse to modify camera position, selected objects, or lights.

Keyboard Controls

Translation (Normal Mode)

Key Action
W Move forward
S Move backward
A Strafe left
D Strafe right
Q Move up
E Move down

Rotation (Extend Mode)

Hold Shift to enable rotation mode:

Key Action
W / S Pitch up/down (rotate around right axis)
A / D Roll left/right (rotate around up axis)
Q / E Yaw left/right (rotate around forward axis)

Property Mode

Press P to toggle property mode. In property mode, the following keys modify the selected object's properties:

Key Action
R Modify object-specific property
H Modify object-specific property
T Modify object-specific property

The R, H, T keys behave differently based on the selected object type:

Object R key H key T key
Sphere Modify radius - -
Cylinder Modify radius Modify height -
Cone - Modify height Modify theta

Other Controls

Key Action
P Toggle property mode
Shift+L Cycle through lights
U Toggle UI overlay
R Reset scene to initial state
ESC Exit application

Note: When not in property mode, R resets the scene.

Mouse Controls

Button Action
Left Click Select object at cursor
Right Click Deselect and select camera

Modes

Normal Mode (Default)

Translation controls move the selected object (or camera if no object selected) using WASD+QE keys.

Extend Mode (Shift Held)

When Shift is held, WASD+QE keys rotate the selected object or camera using Rodrigues' rotation formula around the camera's basis vectors.

Property Mode (P Toggled)

When property mode is enabled, R/H/T keys modify specific properties of the selected object based on its type. This mode does not affect translation or rotation.

Implementation

Event Handling

src/context/
├── hooks/handle/
│   ├── handle_keypress.c    # Key down events
│   ├── handle_keyrelease.c  # Key up events
│   └── handle_mousepress.c # Mouse button events
├── hooks/dispatch/
│   ├── dispatch_translate.c   # Movement dispatch
│   ├── dispatch_rotate.c  # Rotation dispatch
│   └── dispatch_property.c  # Property changes
└── hooks/tween/
    ├── tween_lerp_update.c  # Linear interpolation
    └── tween_slerp_update.c # Spherical interpolation

Tween System

Smooth animations using linear interpolation (LERP) and spherical LERP (SLERP):

typedef struct s_tween
{
    t_vec3 *curr;       // Current position
    t_vec3 target;     // Target position
    t_bool (*update)(t_tween *tw, float t);  // Interpolation function
} t_tween;

Rodrigues Rotation

Rotation uses the Rodrigues rotation formula:

v_rot = v*cos(θ) + (k × v)*sin(θ) + k*(k·v)*(1 - cos(θ))

where k is the rotation axis and θ is the rotation angle.

Configuration

Tweaking parameters in includes/config.h:

#define TWEEN_FACTOR  0.2f   // Interpolation factor
#define TRANS_SPEED  1.2f   // Translation speed
#define ROTATE_ANGLE 0.2f    // Rotation angle per key
#define PROP_INCREMENT 0.5f   // Property increment