Update to 2018_v4 image and new build system. (#598)

* Revert "Force OpenCV to 3.1.0 (#602)"

This reverts commit 50ed55e8e2.

* Removes Simulation

* Removes old build system

* Removes old gtest

* Adds new gmock and gtest

* Updates to new ni-libraries

* removes MyRobot (to be replaced)

* moves files to new location

* Adds new sim backend and new test executables

* updates .styleguide and .gitignore

* Changes cpp WPILibVersion to a function

MSVC throws an AV with the old version.

* Disables USBCamera on all systems except for linux

* 2018 NI Libraries

* New build system

wpilibc/src/main/native/include/AnalogTriggerOutput.h

@@ -0,0 +1,73 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2008-2017. All Rights Reserved.                        */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#pragma once
+
+#include "DigitalSource.h"
+#include "HAL/AnalogTrigger.h"
+
+namespace frc {
+
+class AnalogTrigger;
+
+/**
+ * Class to represent a specific output from an analog trigger.
+ *
+ * This class is used to get the current output value and also as a
+ * DigitalSource to provide routing of an output to digital subsystems on the
+ * FPGA such as Counter, Encoder, and Interrupt.
+ *
+ * The TriggerState output indicates the primary output value of the trigger.
+ * If the analog signal is less than the lower limit, the output is false. If
+ * the analog value is greater than the upper limit, then the output is true.
+ * If the analog value is in between, then the trigger output state maintains
+ * its most recent value.
+ *
+ * The InWindow output indicates whether or not the analog signal is inside the
+ * range defined by the limits.
+ *
+ * The RisingPulse and FallingPulse outputs detect an instantaneous transition
+ * from above the upper limit to below the lower limit, and vise versa. These
+ * pulses represent a rollover condition of a sensor and can be routed to an up
+ * / down counter or to interrupts. Because the outputs generate a pulse, they
+ * cannot be read directly. To help ensure that a rollover condition is not
+ * missed, there is an average rejection filter available that operates on the
+ * upper 8 bits of a 12 bit number and selects the nearest outlyer of 3 samples.
+ * This will reject a sample that is (due to averaging or sampling) errantly
+ * between the two limits. This filter will fail if more than one sample in a
+ * row is errantly in between the two limits. You may see this problem if
+ * attempting to use this feature with a mechanical rollover sensor, such as a
+ * 360 degree no-stop potentiometer without signal conditioning, because the
+ * rollover transition is not sharp / clean enough. Using the averaging engine
+ * may help with this, but rotational speeds of the sensor will then be limited.
+ */
+class AnalogTriggerOutput : public DigitalSource {
+  friend class AnalogTrigger;
+
+ public:
+  virtual ~AnalogTriggerOutput();
+  bool Get() const;
+
+  // DigitalSource interface
+  HAL_Handle GetPortHandleForRouting() const override;
+  AnalogTriggerType GetAnalogTriggerTypeForRouting() const override;
+  bool IsAnalogTrigger() const override;
+  int GetChannel() const override;
+
+ protected:
+  AnalogTriggerOutput(const AnalogTrigger& trigger,
+                      AnalogTriggerType outputType);
+
+ private:
+  // Uses reference rather than smart pointer because a user can not construct
+  // an AnalogTriggerOutput themselves and because the AnalogTriggerOutput
+  // should always be in scope at the same time as an AnalogTrigger.
+  const AnalogTrigger& m_trigger;
+  AnalogTriggerType m_outputType;
+};
+
+}  // namespace frc