Adam Green / Mbed 2 deprecated BBTrackball_Sample

Use a Sparkfun Blackberry Trackball Breakout Board as a mouse.

Dependencies:   mbed BBTrackball

acceleration.cpp@0:26bb60735515, 2011-12-11 (annotated)

Committer:
AdamGreen
Date:
Sun Dec 11 05:38:54 2011 +0000
Revision:
0:26bb60735515
Initial version.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AdamGreen 0:26bb60735515 1 /* Copyright 2011 Adam Green (http://mbed.org/users/AdamGreen/)
AdamGreen 0:26bb60735515 2
AdamGreen 0:26bb60735515 3 Licensed under the Apache License, Version 2.0 (the "License");
AdamGreen 0:26bb60735515 4 you may not use this file except in compliance with the License.
AdamGreen 0:26bb60735515 5 You may obtain a copy of the License at
AdamGreen 0:26bb60735515 6
AdamGreen 0:26bb60735515 7 http://www.apache.org/licenses/LICENSE-2.0
AdamGreen 0:26bb60735515 8
AdamGreen 0:26bb60735515 9 Unless required by applicable law or agreed to in writing, software
AdamGreen 0:26bb60735515 10 distributed under the License is distributed on an "AS IS" BASIS,
AdamGreen 0:26bb60735515 11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
AdamGreen 0:26bb60735515 12 See the License for the specific language governing permissions and
AdamGreen 0:26bb60735515 13 limitations under the License.
AdamGreen 0:26bb60735515 14 */
AdamGreen 0:26bb60735515 15 /* Implementation of classes to apply acceleration to input from
AdamGreen 0:26bb60735515 16 Sparkfun's Blackberry Trackball Breakout board.
AdamGreen 0:26bb60735515 17 */
AdamGreen 0:26bb60735515 18 #include <mbed.h>
AdamGreen 0:26bb60735515 19 #include "acceleration.h"
AdamGreen 0:26bb60735515 20
AdamGreen 0:26bb60735515 21 #define ARRAYSIZE(X) (sizeof(X)/sizeof(X[0]))
AdamGreen 0:26bb60735515 22
AdamGreen 0:26bb60735515 23
AdamGreen 0:26bb60735515 24 template<size_t SampleCount,
AdamGreen 0:26bb60735515 25 int DecelerateThreshold,
AdamGreen 0:26bb60735515 26 int AccelerateThreshold,
AdamGreen 0:26bb60735515 27 int MaxAcceleration>
AdamGreen 0:26bb60735515 28 unsigned char CAcceleratedRoller<SampleCount,
AdamGreen 0:26bb60735515 29 DecelerateThreshold,
AdamGreen 0:26bb60735515 30 AccelerateThreshold,
AdamGreen 0:26bb60735515 31 MaxAcceleration>::ClampToUChar(short Value)
AdamGreen 0:26bb60735515 32 {
AdamGreen 0:26bb60735515 33 if (Value < 0)
AdamGreen 0:26bb60735515 34 {
AdamGreen 0:26bb60735515 35 Value = 0;
AdamGreen 0:26bb60735515 36 }
AdamGreen 0:26bb60735515 37 else if (Value > 0xFF)
AdamGreen 0:26bb60735515 38 {
AdamGreen 0:26bb60735515 39 Value = 0xFF;
AdamGreen 0:26bb60735515 40 }
AdamGreen 0:26bb60735515 41
AdamGreen 0:26bb60735515 42 return Value;
AdamGreen 0:26bb60735515 43 }
AdamGreen 0:26bb60735515 44
AdamGreen 0:26bb60735515 45
AdamGreen 0:26bb60735515 46 template<size_t SampleCount,
AdamGreen 0:26bb60735515 47 int DecelerateThreshold,
AdamGreen 0:26bb60735515 48 int AccelerateThreshold,
AdamGreen 0:26bb60735515 49 int MaxAcceleration>
AdamGreen 0:26bb60735515 50 void CAcceleratedRoller<SampleCount,
AdamGreen 0:26bb60735515 51 DecelerateThreshold,
AdamGreen 0:26bb60735515 52 AccelerateThreshold,
AdamGreen 0:26bb60735515 53 MaxAcceleration>::AccumulateSample(short CurrVelocity)
AdamGreen 0:26bb60735515 54 {
AdamGreen 0:26bb60735515 55 unsigned char ClampedVelocity = ClampToUChar(CurrVelocity);
AdamGreen 0:26bb60735515 56
AdamGreen 0:26bb60735515 57 // Calculate a running sum over the last SampleCount velocity samples.
AdamGreen 0:26bb60735515 58 m_VelocitySum -= m_Samples[m_SampleIndex];
AdamGreen 0:26bb60735515 59 m_VelocitySum += ClampedVelocity;
AdamGreen 0:26bb60735515 60 m_Samples[m_SampleIndex] = ClampedVelocity;
AdamGreen 0:26bb60735515 61
AdamGreen 0:26bb60735515 62 m_SampleIndex++;
AdamGreen 0:26bb60735515 63 if (m_SampleIndex >= SampleCount)
AdamGreen 0:26bb60735515 64 {
AdamGreen 0:26bb60735515 65 m_SampleIndex = 0;
AdamGreen 0:26bb60735515 66 }
AdamGreen 0:26bb60735515 67
AdamGreen 0:26bb60735515 68 // As we see a sustained high velocity, increase acceleration and decrease
AdamGreen 0:26bb60735515 69 // as the user slows down the velocity.
AdamGreen 0:26bb60735515 70 if (m_VelocitySum > AccelerateThreshold && m_Acceleration < MaxAcceleration)
AdamGreen 0:26bb60735515 71 {
AdamGreen 0:26bb60735515 72 m_Acceleration++;
AdamGreen 0:26bb60735515 73 }
AdamGreen 0:26bb60735515 74 if (m_VelocitySum < DecelerateThreshold && m_Acceleration > 1)
AdamGreen 0:26bb60735515 75 {
AdamGreen 0:26bb60735515 76 m_Acceleration--;
AdamGreen 0:26bb60735515 77 }
AdamGreen 0:26bb60735515 78 }
AdamGreen 0:26bb60735515 79
AdamGreen 0:26bb60735515 80
AdamGreen 0:26bb60735515 81
AdamGreen 0:26bb60735515 82 void CAcceleratedTrackball::UpdateLEDColourBasedOnMotion(int VelocityX,
AdamGreen 0:26bb60735515 83 int VelocityY,
AdamGreen 0:26bb60735515 84 int ButtonPressed)
AdamGreen 0:26bb60735515 85 {
AdamGreen 0:26bb60735515 86 static const CBBTrackball::SColour RedColour = {255, 0, 0, 0};
AdamGreen 0:26bb60735515 87 static const CBBTrackball::SColour GreenColour = { 0, 255, 0, 0};
AdamGreen 0:26bb60735515 88 static const CBBTrackball::SColour BlueColour = { 0, 0, 255, 0};
AdamGreen 0:26bb60735515 89
AdamGreen 0:26bb60735515 90 // If the trackball is being moved then make it green, otherwise leave it
AdamGreen 0:26bb60735515 91 // red.
AdamGreen 0:26bb60735515 92 if (VelocityX || VelocityY)
AdamGreen 0:26bb60735515 93 {
AdamGreen 0:26bb60735515 94 m_IterationsSinceLastMotion = 0;
AdamGreen 0:26bb60735515 95 SetColour(&GreenColour);
AdamGreen 0:26bb60735515 96 }
AdamGreen 0:26bb60735515 97 else
AdamGreen 0:26bb60735515 98 {
AdamGreen 0:26bb60735515 99 if (m_IterationsSinceLastMotion > 250)
AdamGreen 0:26bb60735515 100 {
AdamGreen 0:26bb60735515 101 SetColour(&RedColour);
AdamGreen 0:26bb60735515 102 }
AdamGreen 0:26bb60735515 103 else
AdamGreen 0:26bb60735515 104 {
AdamGreen 0:26bb60735515 105 m_IterationsSinceLastMotion++;
AdamGreen 0:26bb60735515 106 }
AdamGreen 0:26bb60735515 107 }
AdamGreen 0:26bb60735515 108
AdamGreen 0:26bb60735515 109 // Switch the button to blue when the button is pressed.
AdamGreen 0:26bb60735515 110 if (ButtonPressed)
AdamGreen 0:26bb60735515 111 {
AdamGreen 0:26bb60735515 112 SetColour(&BlueColour);
AdamGreen 0:26bb60735515 113 }
AdamGreen 0:26bb60735515 114 }
AdamGreen 0:26bb60735515 115
AdamGreen 0:26bb60735515 116
AdamGreen 0:26bb60735515 117 void CAcceleratedTrackball::GetState(int& DeltaX, int& DeltaY, int& ButtonPressed)
AdamGreen 0:26bb60735515 118 {
AdamGreen 0:26bb60735515 119 CBBTrackball::SState TrackballState;
AdamGreen 0:26bb60735515 120 short VelocityX;
AdamGreen 0:26bb60735515 121 short VelocityY;
AdamGreen 0:26bb60735515 122
AdamGreen 0:26bb60735515 123 CBBTrackball::GetState(&TrackballState);
AdamGreen 0:26bb60735515 124
AdamGreen 0:26bb60735515 125 m_UpAcceleration.AccumulateSample(TrackballState.Up);
AdamGreen 0:26bb60735515 126 m_DownAcceleration.AccumulateSample(TrackballState.Down);
AdamGreen 0:26bb60735515 127 m_LeftAcceleration.AccumulateSample(TrackballState.Left);
AdamGreen 0:26bb60735515 128 m_RightAcceleration.AccumulateSample(TrackballState.Right);
AdamGreen 0:26bb60735515 129
AdamGreen 0:26bb60735515 130 // NOTE: The breakout board is rotated 90 degrees on my breadboard.
AdamGreen 0:26bb60735515 131 VelocityX = TrackballState.Up * m_UpAcceleration.Acceleration() -
AdamGreen 0:26bb60735515 132 TrackballState.Down * m_DownAcceleration.Acceleration();
AdamGreen 0:26bb60735515 133 VelocityY = TrackballState.Right * m_RightAcceleration.Acceleration() -
AdamGreen 0:26bb60735515 134 TrackballState.Left * m_LeftAcceleration.Acceleration();
AdamGreen 0:26bb60735515 135
AdamGreen 0:26bb60735515 136 UpdateLEDColourBasedOnMotion(VelocityX, VelocityY, TrackballState.ButtonPressed);
AdamGreen 0:26bb60735515 137
AdamGreen 0:26bb60735515 138 DeltaX = VelocityX;
AdamGreen 0:26bb60735515 139 DeltaY = VelocityY;
AdamGreen 0:26bb60735515 140 ButtonPressed = TrackballState.ButtonPressed;
AdamGreen 0:26bb60735515 141 }