From 7b2cc10d4a9f7464589e614d449a804dcfd1ec76 Mon Sep 17 00:00:00 2001
From: Jesse Vincent <jesse@keyboard.io>
Date: Wed, 11 Jan 2017 20:22:46 -0800
Subject: [PATCH] Switch mouse keys to use integer math. This removes the last
 use of floating point math in the Model 01 core, saving us a good few K of
 program space

---
 .../src/Keyboardio-MouseKeys.cpp              | 16 +++--
 .../Keyboardio-MouseKeys/src/MouseWrapper.cpp | 58 +++++++++----------
 .../Keyboardio-MouseKeys/src/MouseWrapper.h   | 21 ++-----
 3 files changed, 46 insertions(+), 49 deletions(-)

diff --git a/libraries/Keyboardio-MouseKeys/src/Keyboardio-MouseKeys.cpp b/libraries/Keyboardio-MouseKeys/src/Keyboardio-MouseKeys.cpp
index 7c3b713a..aba457a0 100644
--- a/libraries/Keyboardio-MouseKeys/src/Keyboardio-MouseKeys.cpp
+++ b/libraries/Keyboardio-MouseKeys/src/Keyboardio-MouseKeys.cpp
@@ -5,19 +5,27 @@
 #include "KeyboardioFirmware.h"
 
 static void handle_mouse_key_event(Key mappedKey, uint8_t keyState) {
+    if (key_toggled_off(keyState)) {
+	    if (mappedKey.keyCode & KEY_MOUSE_UP || mappedKey.keyCode & KEY_MOUSE_DOWN) {
+		MouseWrapper.mouseActiveForCyclesY=0;
+	    }
+	    if (mappedKey.keyCode & KEY_MOUSE_LEFT || mappedKey.keyCode & KEY_MOUSE_RIGHT) {
+		MouseWrapper.mouseActiveForCyclesX=0;
+	    } 
+    }
+
     if (!key_is_pressed(keyState))
         return;
 
     if (mappedKey.keyCode & KEY_MOUSE_UP) {
         MouseWrapper.move(0,-1);
-    }
-    if (mappedKey.keyCode & KEY_MOUSE_DOWN) {
+    } else if (mappedKey.keyCode & KEY_MOUSE_DOWN) {
         MouseWrapper.move(0,1);
     }
+
     if (mappedKey.keyCode & KEY_MOUSE_LEFT) {
         MouseWrapper.move(-1,0);
-    }
-    if (mappedKey.keyCode & KEY_MOUSE_RIGHT) {
+    } else if (mappedKey.keyCode & KEY_MOUSE_RIGHT) {
         MouseWrapper.move(1,0);
     }
 }
diff --git a/libraries/Keyboardio-MouseKeys/src/MouseWrapper.cpp b/libraries/Keyboardio-MouseKeys/src/MouseWrapper.cpp
index dfe55eb5..ccf4fb6a 100644
--- a/libraries/Keyboardio-MouseKeys/src/MouseWrapper.cpp
+++ b/libraries/Keyboardio-MouseKeys/src/MouseWrapper.cpp
@@ -77,43 +77,43 @@ void MouseWrapper_::warp(uint8_t warp_cmd) {
 }
 
 
+// cubic wave function based on code from FastLED
+uint8_t MouseWrapper_::acceleration(uint8_t cycles) {
+    uint8_t i = cycles;
 
-double MouseWrapper_::acceleration (double cycles) {
-    double accel = (atan((cycles * ACCELERATION_CLIMB_SPEED)-ACCELERATION_RUNWAY) + ATAN_LIMIT) * ACCELERATION_MULTIPLIER;
-    if (accel < ACCELERATION_FLOOR) {
-        accel = ACCELERATION_FLOOR;
+    if( i & 0x80) {
+        i = 255 - i;
     }
-    return accel;
+
+    i = i << 1;
+
+    uint8_t ii = (i*i) >> 8;
+    uint8_t iii = (ii*i) >> 8;
+
+    i =  (( (3 * (uint16_t)(ii)) - ( 2 * (uint16_t)(iii))) / 2) + ACCELERATION_FLOOR;
+
+    if ( i > ACCELERATION_CEIL) {
+	i = ACCELERATION_CEIL;
+    }
+    return i;
 }
 
+
 void MouseWrapper_::move( int8_t x, int8_t y) {
+    int16_t moveX =0;
+    int16_t moveY = 0;
+    if (x != 0 ) {
+    	if (mouseActiveForCyclesX < 255) { mouseActiveForCyclesX++;}
+        moveX = (x * acceleration(mouseActiveForCyclesX));
+    }
+    if (y != 0) {
+    	if (mouseActiveForCyclesY < 255) { mouseActiveForCyclesY++;}
+        moveY = (y * acceleration(mouseActiveForCyclesY));
 
-    if (x != 0 || y != 0) {
-        mouseActiveForCycles++;
-        double accel = (double) acceleration(mouseActiveForCycles);
-        float moveX = 0;
-        float moveY = 0;
-        if (x > 0) {
-            moveX = (x * accel) + carriedOverX;
-            carriedOverX = moveX - floor(moveX);
-        } else if (x < 0) {
-            moveX = (x * accel) - carriedOverX;
-            carriedOverX = ceil(moveX) - moveX;
-        }
-
-        if (y > 0) {
-            moveY = (y * accel) + carriedOverY;
-            carriedOverY = moveY - floor(moveY);
-        } else if (y < 0) {
-            moveY = (y * accel) - carriedOverY;
-            carriedOverY = ceil(moveY) - moveY;
-        }
+    }
+	
         end_warping();
-
         Mouse.move(moveX, moveY, 0);
-    } else {
-        mouseActiveForCycles = 0;
-    }
 
 }
 
diff --git a/libraries/Keyboardio-MouseKeys/src/MouseWrapper.h b/libraries/Keyboardio-MouseKeys/src/MouseWrapper.h
index afffbbcd..f5413a17 100644
--- a/libraries/Keyboardio-MouseKeys/src/MouseWrapper.h
+++ b/libraries/Keyboardio-MouseKeys/src/MouseWrapper.h
@@ -26,16 +26,8 @@
 
 // we want the whole s curve, not just the bit
 // that's usually above the x and y axes;
-#define ATAN_LIMIT 1.57079633
-#define ACCELERATION_FLOOR 0.25
-#define ACCELERATION_MULTIPLIER 5
-#define  ACCELERATION_RUNWAY 5
-// Climb speed is how fast we get to max speed
-// 1 is "instant"
-// 0.05 is just right
-// 0.001 is insanely slow
-
-#define ACCELERATION_CLIMB_SPEED  0.05
+#define ACCELERATION_FLOOR 2
+#define ACCELERATION_CEIL 50
 
 
 class MouseWrapper_ {
@@ -45,20 +37,17 @@ class MouseWrapper_ {
     void warp(uint8_t warp_cmd);
     void press_button(uint8_t button);
     void release_button(uint8_t button);
+    uint8_t mouseActiveForCyclesX = 0;
+    uint8_t mouseActiveForCyclesY = 0;
 
   private:
-    double mouseActiveForCycles = 0;
-    float carriedOverX = 0;
-    float carriedOverY = 0;
-
-
     uint16_t next_width = 0;
     uint16_t next_height = 0;
     uint16_t section_top = 0;
     uint16_t section_left = 0;
     boolean is_warping = false;
 
-    double acceleration (double cycles);
+    uint8_t acceleration (uint8_t cycles);
     void begin_warping();
     void end_warping();
     void warp_jump(long left, long top, long height, long width);