rewrite progress

src/chart_manager.rs

@@ -104,8 +104,8 @@ impl ChartManager {
                     false => x - step,
                 };
 
-                let tmp1: f64 = self.function.run(x);
-                let tmp2: f64 = self.function.run(x2);
+                let tmp1: f64 = self.function.run_func(x);
+                let tmp2: f64 = self.function.run_func(x2);
 
                 // Chooses the y value who's absolute value is the smallest
                 let mut output = match tmp2.abs() > tmp1.abs() {

src/egui_app.rs

@@ -34,6 +34,7 @@ pub struct MathApp {
 }
 
 impl Default for MathApp {
+    #[inline]
     fn default() -> Self {
         let def_func = "x^2".to_string();
         let def_min_x = -10.0;
@@ -102,15 +103,19 @@ impl MathApp {
 }
 
 impl epi::App for MathApp {
+    
+    // The name of the program (displayed when running natively as the window title)
     fn name(&self) -> &str { "Integral Demonstration" }
 
-    /// Called once before the first frame.
+    // Called once before the first frame.
+    #[inline]
     fn setup(
         &mut self, _ctx: &egui::Context, _frame: &epi::Frame, _storage: Option<&dyn epi::Storage>,
     ) {
     }
 
-    /// Called each time the UI needs repainting, which may be many times per second.
+    // Called each time the UI needs repainting, which may be many times per second.
+    #[inline]
     fn update(&mut self, ctx: &egui::Context, _frame: &epi::Frame) {
         let Self {
             func_str,

src/function.rs

@@ -0,0 +1,182 @@
+use meval::Expr;
+use egui::plot::Value;
+use egui::widgets::plot::Bar;
+
+const RESOLUTION: f64 = 1000.0;
+
+
+// Struct that stores and manages the output of a function
+pub struct FunctionOutput {
+    // The actual line graph
+    back: Vec<Value>,
+
+    // Integral information
+    front: Option<(Vec<Bar>, f64)>,
+}
+
+impl FunctionOutput {
+    #[inline]
+    pub fn new(back: Vec<Value>, front: Option<(Vec<Bar>, f64)>) -> Self {
+        Self {
+            back,
+            front,
+        }
+    }
+
+    #[inline]
+    fn has_integral(&self) -> bool {
+        match self.front {
+            Some(x) => true,
+            None => false,
+        }
+    }
+}
+
+pub struct Function {
+    function: Box<dyn Fn(f64) -> f64>,
+    func_str: String,
+    min_x: f64,
+    max_x: f64,
+    back_cache: Cache<Vec<Value>>,
+    front_cache: Cache<(Vec<Bar>, f64)>,
+
+    integral: bool,
+    integral_min_x: f64,
+    integral_max_x: f64,
+    integral_num: usize,
+}
+
+impl Function {
+    pub fn new(func_str: String, min_x: f64, max_x: f64, integral: bool, integral_min_x: Option<f64>, integral_max_x: Option<f64>, integral_num: Option<usize>) -> Self {
+
+        // Makes sure proper arguments are passed when integral is enabled
+        if integral {
+            if integral_min_x.is_none() {
+                panic!("Invalid arguments: integral_min_x is None, but integral is enabled.")
+            } else if integral_max_x.is_none() {
+                panic!("Invalid arguments: integral_max_x is None, but integral is enabled.")
+            } else if integral_num.is_none() {
+                panic!("Invalid arguments: integral_num is None, but integral is enabled.")
+            }
+        }
+
+        let expr: Expr = func_str.parse().unwrap();
+        let func = expr.bind("x").unwrap();
+        Self {
+            function: Box::new(func),
+            func_str,
+            min_x,
+            max_x,
+            back_cache: Cache::new_empty(),
+            front_cache: Cache::new_empty(),
+            integral,
+            integral_min_x: match integral_min_x {
+                Some(x) => x,
+                None => f64::NAN,
+            },
+            integral_max_x: match integral_max_x {
+                Some(x) => x,
+                None => f64::NAN,
+            },
+            integral_num: match integral_num {
+                Some(x) => x,
+                None => f64::NAN,
+            },
+        }
+    }
+
+    // Runs the internal function to get values
+    #[inline]
+    fn run_func(&self, x: f64) -> f64 { (self.function)(x) }
+
+    #[inline]
+    pub fn update(&mut self, func_str: String, min_x: f64, max_x: f64, integral: bool, integral_min_x: Option<f64>, integral_max_x: Option<f64>, integral_num: Option<usize>) {
+
+        // If the function string changes, just wipe and restart from scratch
+        if func_str != self.func_str {
+            *self = Self::new(func_str, min_x, max_x, integral, integral_min_x, integral_max_x, integral_num);
+            return;
+        }
+
+
+        if (min_x != self.min_x) | (max_x != self.max_x) {
+            self.back_cache.invalidate();
+            self.min_x = min_x;
+            self.max_x = max_x;
+        }
+
+        // Makes sure proper arguments are passed when integral is enabled
+        if integral {
+            if integral_min_x.is_none() {
+                panic!("Invalid arguments: integral_min_x is None, but integral is enabled.")
+            } else if integral_max_x.is_none() {
+                panic!("Invalid arguments: integral_max_x is None, but integral is enabled.")
+            } else if integral_num.is_none() {
+                panic!("Invalid arguments: integral_num is None, but integral is enabled.")
+            }
+
+            if (integral_min_x != Some(self.integral_min_x)) | (integral_max_x != Some(self.integral_max_x)) | (integral_num != Some(self.integral_num)) {
+                self.front_cache.invalidate();
+                self.integral_min_x = integral_min_x.expect("");
+                self.integral_max_x = integral_max_x.expect("");
+                self.integral_num = integral_num.expect("");
+            }
+        }
+
+    }
+
+
+    #[inline]
+    pub fn run(&mut self) -> FunctionOutput {
+        let absrange = (self.max_x - self.min_x).abs();
+        let output: Vec<(f64, f64)> = (1..=self.resolution)
+            .map(|x| ((x as f64 / RESOLUTION) * absrange) + self.min_x_back)
+            .map(|x| (x, self.function.run(x)))
+            .collect();
+        output
+    }
+
+    #[inline]
+    pub fn str_compare(&self, other_string: String) -> bool { self.func_str == other_string }
+
+    #[inline]
+    pub fn get_step(&self) -> f64 { (self.integral_min_x - self.integral_max_x).abs() / (self.num_interval as f64) }
+
+    // Creates and does the math for creating all the rectangles under the graph
+    #[inline]
+    fn integral_rectangles(&self, step: f64) -> (Vec<(f64, f64)>, f64) {
+        let half_step = step / 2.0;
+        let data2: Vec<(f64, f64)> = (0..self.num_interval)
+            .map(|e| {
+                let x: f64 = ((e as f64) * step) + self.integral_min_x;
+
+                // Makes sure rectangles are properly handled on x values below 0
+                let x2: f64 = match x > 0.0 {
+                    true => x + step,
+                    false => x - step,
+                };
+
+                let tmp1: f64 = self.run_func(x);
+                let tmp2: f64 = self.run_func(x2);
+
+                // Chooses the y value who's absolute value is the smallest
+                let mut output = match tmp2.abs() > tmp1.abs() {
+                    true => (x, tmp1),
+                    false => (x2, tmp2),
+                };
+
+                // Applies `half_step` in order to make the bar graph display properly
+                if output.0 > 0.0 {
+                    output.0 += half_step;
+                } else {
+                    output.0 -= half_step;
+                }
+
+                output
+            })
+            .filter(|(_, y)| !y.is_nan())
+            .collect();
+        let area: f64 = data2.iter().map(|(_, y)| y * step).sum(); // sum of all rectangles' areas
+        (data2, area)
+    }
+}

src/lib.rs

@@ -4,6 +4,7 @@
 mod chart_manager;
 mod egui_app;
 mod misc;
+mod function;
 
 #[cfg(target_arch = "wasm32")]
 use wasm_bindgen::prelude::*;

src/main.rs

@@ -3,6 +3,7 @@ mod egui_app;
 // These 2 are needed for rust-analyzer to work in vscode.
 mod chart_manager;
 mod misc;
+mod function;
 
 // For running the program natively! (Because why not?)
 #[cfg(not(target_arch = "wasm32"))]

src/misc.rs

@@ -5,6 +5,7 @@ EXTREMELY Janky function that tries to put asterisks in the proper places to be
 One limitation though, variables with multiple characters like `pi` cannot be multiplied (like `pipipipi` won't result in `pi*pi*pi*pi`). But that's such a niche use case (and that same thing could be done by using exponents) that it doesn't really matter.
 In the future I may want to completely rewrite this or implement this natively into mevel-rs (which would probably be good to do)
 */
+#[inline]
 pub fn add_asterisks(function_in: String) -> String {
     let function = function_in.replace("log10(", "log(").replace("pi", "π"); // pi -> π and log10 -> log
     let valid_variables: Vec<char> = "xeπ".chars().collect();
@@ -78,6 +79,7 @@ pub fn add_asterisks(function_in: String) -> String {
 }
 
 // Tests function to make sure it's able to be parsed. Returns the string of the Error produced, or an empty string if it runs successfully.
+#[inline]
 pub fn test_func(function_string: String) -> String {
     // Factorials do not work, and it would be really difficult to make them work
     if function_string.contains('!') {
@@ -108,35 +110,12 @@ pub fn test_func(function_string: String) -> String {
 }
 
 // Rounds f64 to specific number of digits
+#[inline]
 pub fn digits_precision(x: f64, digits: usize) -> f64 {
     let large_number: f64 = 10.0_f64.powf(digits as f64);
     (x * large_number).round() / large_number
 }
 
-pub struct Function {
-    function: Box<dyn Fn(f64) -> f64>,
-    func_str: String,
-}
-
-impl Function {
-    pub fn from_string(func_str: String) -> Self {
-        let expr: Expr = func_str.parse().unwrap();
-        let func = expr.bind("x").unwrap();
-        Self {
-            function: Box::new(func),
-            func_str,
-        }
-    }
-
-    #[inline]
-    pub fn run(&self, x: f64) -> f64 { (self.function)(x) }
-
-    pub fn str_compare(&self, other_string: String) -> bool { self.func_str == other_string }
-
-    #[allow(dead_code)]
-    pub fn get_string(&self) -> String { self.func_str.clone() }
-}
-
 pub struct Cache<T> {
     backing_data: Option<T>,
 }