From 2ab8d0a68aa667c8fc8fec1f750928b3fdf6f679 Mon Sep 17 00:00:00 2001
From: mintey <sam@minty.moe>
Date: Tue, 2 Mar 2021 22:47:32 +0200
Subject: [PATCH] some simple mouse acceleration

---
 smol_gkos.ino | 26 ++++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

diff --git a/smol_gkos.ino b/smol_gkos.ino
index e13fa69..f3c8dd8 100644
--- a/smol_gkos.ino
+++ b/smol_gkos.ino
@@ -145,7 +145,13 @@ byte mouse_left = 0;
 byte mouse_right = 0;
 bool mouse_button = false;
 
-const int mouse_scroll_sensitivity = 10;
+const int num_mouse_samples = 10;
+int current_mouse_sample = 0;
+int mouse_movement_sample = 0;
+float mouse_acceleration = 0.0f;
+const float mouse_accel_factor = 0.7f;
+
+const int mouse_scroll_sensitivity = 6;
 int mouse_scroll_dist = 0;
 bool mouse_middle_pressed = false;
 bool mouse_scrolled = false;
@@ -167,10 +173,9 @@ void setup() {
     pinMode(PIN_LED2, OUTPUT);
     pinMode(PIN_LED3, OUTPUT);
 
-    // poll trackball at 100Hz
-    trackball_timer.begin(trackball_isr, 1000);
+    // poll trackball at 10kHz
+    trackball_timer.begin(trackball_isr, 100);
 
-    Serial.begin(115200);
     Wire.begin();
 }
 
@@ -238,6 +243,7 @@ void loop() {
                             if (!mouse_scrolled)
                                 Mouse.click(MOUSE_MIDDLE);
                             mouse_middle_pressed = mouse_scrolled = false;
+                            mouse_scroll_dist = 0;
                             break;
                     }
                 }
@@ -264,6 +270,15 @@ void loop() {
 
         int mouse_x = mouse_right - mouse_left;
         int mouse_y = mouse_down - mouse_up;
+
+        mouse_movement_sample += abs(mouse_x) + abs(mouse_y);
+        current_mouse_sample++;
+        if (current_mouse_sample > num_mouse_samples) {
+            current_mouse_sample = 0;
+            mouse_acceleration = 1.0f + mouse_movement_sample * mouse_accel_factor;
+            mouse_movement_sample = 0;
+        }
+
         if (mouse_middle_pressed) {
             mouse_scroll_dist += mouse_y;
             if (abs(mouse_scroll_dist) > mouse_scroll_sensitivity) {
@@ -272,8 +287,7 @@ void loop() {
                 mouse_scrolled = true;
             }
         } else {
-            Mouse.move(sign(mouse_x) * mouse_x * mouse_x,
-                sign(mouse_y) * mouse_y * mouse_y);
+            Mouse.move(mouse_x * mouse_acceleration, mouse_y * mouse_acceleration);
         }
 
         trackball_update = false;