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Diffstat (limited to 'src/input/mod.rs')
| -rw-r--r-- | src/input/mod.rs | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/src/input/mod.rs b/src/input/mod.rs new file mode 100644 index 0000000..e8b1821 --- /dev/null +++ b/src/input/mod.rs @@ -0,0 +1,200 @@ +//! Input with binding abstraction +//! +//! Binding keys or combinations to specific actions with just raylib alone is difficult to handle in +//! input-heavy applications, as opposed to games. This is an optimisation effort. To understand how +//! it works, the first thing to know is that there are two main modes for bindings, which are local +//! and global. A local binding is specific to a certain area of the window and is used to block the +//! mouse from being sent to many different targets (think of a pop-up window over the editor, which +//! must capture the mouse). Global bindings will be processed as long as no local binding has +//! prevalence, but they do not have an area that needs to be managed by a handler. +//! +//! In summary, the local <-> global distinction is used to capture the mouse. +//! +//! Some elements want to capture the keyboard, for instance, when activating a text box, the text +//! input should only go to this box, but should a tool be bound to a character, it should not +//! activate when typing. For this purpose, any element may seize control as long as no other element +//! still has the focus. A channel is opened and no bindings will be processed. Instead the text +//! together with a few control characters is relayed directly to the channel, until the receiver +//! hangs up. +//! +//! In summary, a channel is used to seize control of the keyboard when typing into an element. + +pub mod binding; +pub mod button; + +pub use binding::*; +pub use button::*; + +use crate::math::{ExactSurface, Rect, Vec2}; +use crate::stable_vec::StableVec; +use raylib::ffi::KeyboardKey; +use raylib::RaylibHandle; +use std::collections::HashMap; +use std::sync::mpsc::{self, Receiver, Sender}; + +/// Input and binding handler this should only be created once per instance. +pub struct Input { + global_bindings: HashMap<Binding, bool>, + local_bindings: StableVec<(Rect<u16>, HashMap<Binding, bool>)>, + last_text: String, + text_pipe: Option<Sender<char>>, + mouse_pos: Vec2<u16>, +} + +impl Input { + /// Create a new Input and binding handler. + pub fn new(rl: &RaylibHandle) -> Self { + Self { + global_bindings: HashMap::new(), + local_bindings: StableVec::new(), + last_text: String::new(), + text_pipe: None, + mouse_pos: Vec2::new(rl.get_mouse_x() as u16, rl.get_mouse_y() as u16), + } + } + + /// Must be called on every frame of the program, since keypresses will be processed here. This + /// will not activate the binding function directly, since raylib is heavily polling focused. + pub fn update(&mut self, rl: &mut RaylibHandle) { + self.mouse_pos = Vec2::new(rl.get_mouse_x() as u16, rl.get_mouse_y() as u16); + /* Read the next character to be sent with some extra characters + * raylib doesn't recognize to be valid. + */ + let c = if rl.is_key_pressed(KeyboardKey::KEY_ENTER) { + Some('\n') + } else if rl.is_key_pressed(KeyboardKey::KEY_ESCAPE) { + Some('\x1B') + } else if rl.is_key_pressed(KeyboardKey::KEY_BACKSPACE) { + Some('\x7f') + } else { + rl.get_key_pressed_number().map(|c| c as u8 as char) + }; + + /* Send the character to the listening entity or push it to the text that + * is currently being read for the keybindings. + */ + if let Some(text_pipe) = self.text_pipe.as_mut() { + if let Some(c) = c { + if text_pipe.send(c).is_err() { + self.last_text.push(c); + self.text_pipe = None; + } + } + } else if let Some(c) = c { + self.last_text.push(c); + } + + /* Update the local parts. The local stack has priority over the global + * bindings, so it is processed first, with the priority going from the + * top of the stack to the bottom in that order (reversed vec order) + */ + let mut mouse_blocked = false; + for (_, (rect, bindings)) in self.local_bindings.id_iter_mut().rev() { + if rect.contains_point(&self.mouse_pos) { + for (binding, state) in &mut bindings.iter_mut() { + *state = binding.is_pressed( + !mouse_blocked, + self.text_pipe.is_none(), + &self.last_text, + rl, + ); + + if *state { + self.last_text.clear(); + } + } + + mouse_blocked = true; + break; + } + } + + /* Process the global bindings, as long as nothing prevents the bindings + * from being processed like a local binding or the text being captured. + */ + for (binding, state) in self.global_bindings.iter_mut() { + *state = binding.is_pressed( + !mouse_blocked, + self.text_pipe.is_none(), + &self.last_text, + rl, + ); + + if *state { + self.last_text.clear(); + } + } + } + + /// Add a global binding. This is necessary so the input knows which key presses to monitor. + pub fn add_global(&mut self, binding: Binding) -> bool { + self.global_bindings.insert(binding, false).is_none() + } + + /// Add a local binding handler for the given area. Returns a unique and unchanging handler id. + /// Handlers with higher ids (that have been added later) are preferred over old handlers. + pub fn add_local_handler(&mut self, area: Rect<u16>) -> usize { + self.local_bindings.push((area, HashMap::new())) + } + + /// Add a local binding for the given handler. + pub fn add_local(&mut self, handler_id: usize, binding: Binding) -> bool { + self.local_bindings + .get_mut(handler_id) + .expect("Handler does not exist") + .1 + .insert(binding, false) + .is_none() + } + + /// Update the binding rectangle of a handler. + pub fn set_binding_rect(&mut self, handler_id: usize, rect: Rect<u16>) { + self.local_bindings + .get_mut(handler_id) + .expect("Handler does not exist") + .0 = rect; + } + + /// Check if a global binding has been activated this frame. If so, it returns true. + /// This will only activate once, so there is no need to worry about multiple function calls + /// when the user keeps the button down. + pub fn poll_global(&mut self, binding: &Binding) -> bool { + let state = self.global_bindings.get_mut(&binding); + if state.is_none() { + error!("Tried to poll binding that isn't registered."); + return false; + } + + *state.unwrap() + } + + /// Like `poll_global` bun instead checks the bindings of the local handler with the given id. + pub fn poll_local(&mut self, handler_id: usize, binding: &Binding) -> bool { + let (_, bindings) = self + .local_bindings + .get_mut(handler_id) + .expect("Invalid binding handler id"); + + let state = bindings.get_mut(&binding); + if state.is_none() { + error!("Tried to poll binding that isn't registered."); + return false; + } + + *state.unwrap() + } + + /// Attempts to capture all keyboard input from here on. If no other component is currently + /// capturing, it returns a receiver that can be used. When the entity no longer wants to + /// capture the keyboard, control must be returned by dropping the receiver. + pub fn try_capture_keyboard(&mut self) -> Option<Receiver<char>> { + if self.text_pipe.is_some() { + return None; + } + + let (tx, rx) = mpsc::channel(); + self.text_pipe = Some(tx); + + Some(rx) + } +} |
