add multiple functions to canvas

1 files changed, 47 insertions, 27 deletions

diff --git a/src/ui/graph.rs b/src/ui/graph.rs
index 63e1c43..83d90f8 100644
--- a/src/ui/graph.rs
+++ b/src/ui/graph.rs
@@ -16,17 +16,16 @@ use crate::{
 #[derive(Default)]
 pub struct GraphCanvas {
     graph: Cache,
-    pub func: Mutex<FunctionCache>,
-    pub ctx: Context,
+    funcs: Mutex<Vec<Option<FunctionCache>>>,
+    ctx: Context,
 }
 
 impl GraphCanvas {
-    pub fn new(fstr: &String) -> Self {
+    pub fn new() -> Self {
         let ctx = Context::commonsense();
-        let func = ExpressionFunction::from_string(fstr.clone(), ctx.operations());
         Self {
             graph: Cache::default(),
-            func: Mutex::new(FunctionCache::new(func)),
+            funcs: Mutex::new(Vec::new()),
             ctx,
         }
     }
@@ -34,6 +33,26 @@ impl GraphCanvas {
     pub fn clear(&self) {
         self.graph.clear();
     }
+
+    pub fn push(&mut self, f: &str) {
+        if let Ok(f) = ExpressionFunction::from_string(f.to_string(), self.ctx.operations()) {
+            self.funcs.lock().unwrap().push(Some(FunctionCache::new(f)));
+        } else {
+            self.funcs.lock().unwrap().push(None);
+        }
+    }
+
+    pub fn set(&mut self, i: usize, f: &str) {
+        if let Ok(f) = ExpressionFunction::from_string(f.to_string(), self.ctx.operations()) {
+            self.funcs.lock().unwrap()[i] = Some(FunctionCache::new(f));
+        } else {
+            self.funcs.lock().unwrap().push(None);
+        }
+    }
+
+    pub fn remove(&mut self, i: usize) {
+        self.funcs.lock().unwrap().remove(i);
+    }
 }
 
 #[derive(Copy, Clone)]
@@ -190,28 +209,29 @@ impl canvas::Program<Message, Renderer> for GraphCanvas {
             });
 
             let step = (step / 10).max(1);
-            let mut y1 = self
-                .func
+
+            for func in self
+                .funcs
                 .lock()
                 .unwrap()
-                .eval(Complex::new(rect.x as f64, 0.0), &self.ctx)
-                .real as f32;
-            for x in (rect.x as i64..(rect.x + rect.width) as i64).step_by(step) {
-                for d in 0..10 {
-                    let d = d as f32 / 10.0;
-                    let x1 = x as f32 + d * step as f32;
-                    let x2 = x as f32 + (d + 0.1) * step as f32;
-                    let y2 = self
-                        .func
-                        .lock()
-                        .unwrap()
-                        .eval(Complex::new(x2 as f64, 0.0), &self.ctx)
-                        .real as f32;
-                    if y1.is_finite() && !y1.is_nan() && y2.is_finite() && !y2.is_nan() {
-                        let line = Path::line(state.map_coords(x1, y1), state.map_coords(x2, y2));
-                        frame.stroke(&line, graphline.clone())
+                .iter_mut()
+                .filter(|f| f.is_some())
+                .map(|f| f.as_mut().unwrap())
+            {
+                let mut y1 = func.eval(Complex::new(rect.x as f64, 0.0), &self.ctx).real as f32;
+                for x in (rect.x as i64..(rect.x + rect.width) as i64).step_by(step) {
+                    for d in 0..10 {
+                        let d = d as f32 / 10.0;
+                        let x1 = x as f32 + d * step as f32;
+                        let x2 = x as f32 + (d + 0.1) * step as f32;
+                        let y2 = func.eval(Complex::new(x2 as f64, 0.0), &self.ctx).real as f32;
+                        if y1.is_finite() && !y1.is_nan() && y2.is_finite() && !y2.is_nan() {
+                            let line =
+                                Path::line(state.map_coords(x1, y1), state.map_coords(x2, y2));
+                            frame.stroke(&line, graphline.clone())
+                        }
+                        y1 = y2;
                     }
-                    y1 = y2;
                 }
             }
         });
@@ -232,7 +252,7 @@ impl canvas::Program<Message, Renderer> for GraphCanvas {
         if let canvas::Event::Mouse(mouse::Event::ButtonPressed(_)) = event {
             state.interaction = Interaction::Grabbing;
             state.last_position = cursor.position();
-            return (event::Status::Captured, Some(Message::UpdateScreen));
+            return (event::Status::Captured, Some(Message::RefreshGraphCanvas));
         }
 
         if let canvas::Event::Mouse(mouse::Event::CursorMoved { position }) = event {
@@ -242,7 +262,7 @@ impl canvas::Program<Message, Renderer> for GraphCanvas {
                     state.center.y += position.y - lp.y;
                 }
                 state.last_position = Some(position);
-                return (event::Status::Captured, Some(Message::UpdateScreen));
+                return (event::Status::Captured, Some(Message::RefreshGraphCanvas));
             }
         }
 
@@ -259,7 +279,7 @@ impl canvas::Program<Message, Renderer> for GraphCanvas {
                         state.scale *= 1.1;
                     }
                     state.scale = state.scale.max(0.000001);
-                    return (event::Status::Captured, Some(Message::UpdateScreen));
+                    return (event::Status::Captured, Some(Message::RefreshGraphCanvas));
                 }
                 _ => {}
             }