6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2024-11-26 08:49:37 +00:00
Code Issues Projects Releases Wiki Activity

Adds status notes.

Browse Source
This commit is contained in:
Thomas Harte 2019-07-08 21:11:12 -04:00
parent 3d8e4f96c8
commit 4bc44666e5
1 changed files with 14 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
Inputs/QuadratureMouse/QuadratureMouse.hpp
View File

@ -17,6 +17,14 @@ namespace Inputs {
/*!
Provides a simple implementation of a Mouse, designed for simple
thread-safe feeding to a machine that accepts quadrature-encoded input.
TEMPORARY SIMPLIFICATION: it is assumed that the caller will be interested
in observing a signal that dictates velocity, sampling the other to
obtain direction only on transitions in the velocity signal.
Or, more concretely, of the two channels per axis, one is accurate only when
the other transitions. Hence the discussion of 'primary' and 'secondary'
channels below. This is intended to be fixed.
*/
class QuadratureMouse: public Mouse {
public:
@ -57,14 +65,19 @@ class QuadratureMouse: public Mouse {
*/
void prepare_step() {
for(int axis = 0; axis < 2; ++axis) {
// Do nothing if there's no motion to communicate.
const int axis_value = axes_[axis];
if(!axis_value) continue;
// Toggle the primary channel and set the secondary for
// negative motion. At present the y axis signals the
// secondary channel the opposite way around from the
// primary.
primaries_[axis] ^= 1;
secondaries_[axis] = primaries_[axis] ^ axis;
if(axis_value > 0) {
-- axes_[axis];
secondaries_[axis] ^= 1;
secondaries_[axis] ^= 1; // Switch to positive motion.
} else {
++ axes_[axis];
}