AP_Camera: add scripting backend

libraries/AP_Camera/AP_Camera.cpp

@@ -17,6 +17,7 @@
 #include "AP_Camera_Mount.h"
 #include "AP_Camera_MAVLink.h"
 #include "AP_Camera_MAVLinkCamV2.h"
+#include "AP_Camera_Scripting.h"
 
 const AP_Param::GroupInfo AP_Camera::var_info[] = {
 
@@ -170,6 +171,12 @@ void AP_Camera::init()
         case CameraType::MAVLINK_CAMV2:
             _backends[instance] = new AP_Camera_MAVLinkCamV2(*this, _params[instance], instance);
             break;
+#endif
+#if AP_CAMERA_SCRIPTING_ENABLED
+        // check for Scripting driver
+        case CameraType::SCRIPTING:
+            _backends[instance] = new AP_Camera_Scripting(*this, _params[instance], instance);
+            break;
 #endif
         case CameraType::NONE:
             break;
@@ -430,6 +437,19 @@ bool AP_Camera::set_auto_focus(uint8_t instance)
     return backend->set_auto_focus();
 }
 
+#if AP_CAMERA_SCRIPTING_ENABLED
+// accessor to allow scripting backend to retrieve state
+// returns true on success and cam_state is filled in
+bool AP_Camera::get_state(uint8_t instance, camera_state_t& cam_state) const
+{
+    auto *backend = get_instance(instance);
+    if (backend == nullptr) {
+        return false;
+    }
+    return backend->get_state(cam_state);
+}
+#endif // #if AP_CAMERA_SCRIPTING_ENABLED
+
 // return backend for instance number
 AP_Camera_Backend *AP_Camera::get_instance(uint8_t instance) const
 {

libraries/AP_Camera/AP_Camera.h

@@ -13,6 +13,17 @@
 #include "AP_Camera_Params.h"
 #include "AP_Mount/AP_Mount_config.h"
 
+#if AP_CAMERA_SCRIPTING_ENABLED
+    // structure and accessors for use by scripting backends
+    typedef struct {
+        uint16_t take_pic_incr; // incremented each time camera is requested to take a picture
+        bool recording_video;   // true when recording video
+        int8_t zoom_step;       // zoom out = -1, hold = 0, zoom in = 1
+        int8_t focus_step;      // focus in = -1, focus hold = 0, focus out = 1
+        bool auto_focus;        // true when auto focusing
+    } camera_state_t;
+#endif
+
 #define AP_CAMERA_MAX_INSTANCES             2       // maximum number of camera backends
 
 // declare backend classes
@@ -23,6 +34,7 @@ class AP_Camera_SoloGimbal;
 class AP_Camera_Mount;
 class AP_Camera_MAVLink;
 class AP_Camera_MAVLinkCamV2;
+class AP_Camera_Scripting;
 
 /// @class	Camera
 /// @brief	Object managing a Photo or video camera
@@ -36,6 +48,7 @@ class AP_Camera {
     friend class AP_Camera_Mount;
     friend class AP_Camera_MAVLink;
     friend class AP_Camera_MAVLinkCamV2;
+    friend class AP_Camera_Scripting;
 
 public:
 
@@ -68,6 +81,9 @@ public:
 #endif
 #if AP_CAMERA_MAVLINKCAMV2_ENABLED
         MAVLINK_CAMV2 = 6,  // MAVLink camera v2
+#endif
+#if AP_CAMERA_SCRIPTING_ENABLED
+        SCRIPTING = 7,  // Scripting backend
 #endif
     };
 
@@ -124,6 +140,12 @@ public:
     // set if vehicle is in AUTO mode
     void set_is_auto_mode(bool enable) { _is_in_auto_mode = enable; }
 
+#if AP_CAMERA_SCRIPTING_ENABLED
+    // accessor to allow scripting backend to retrieve state
+    // returns true on success and cam_state is filled in
+    bool get_state(uint8_t instance, camera_state_t& cam_state) const;
+#endif
+
     // parameter var table
     static const struct AP_Param::GroupInfo var_info[];
 

libraries/AP_Camera/AP_Camera_Backend.h

@@ -82,6 +82,12 @@ public:
     // send camera feedback message to GCS
     void send_camera_feedback(mavlink_channel_t chan) const;
 
+#if AP_CAMERA_SCRIPTING_ENABLED
+    // accessor to allow scripting backend to retrieve state
+    // returns true on success and cam_state is filled in
+    virtual bool get_state(camera_state_t& cam_state) const { return false; }
+#endif
+
 protected:
 
     // references

libraries/AP_Camera/AP_Camera_Params.cpp

@@ -8,7 +8,7 @@ const AP_Param::GroupInfo AP_Camera_Params::var_info[] = {
     // @Param: _TYPE
     // @DisplayName: Camera shutter (trigger) type
     // @Description: how to trigger the camera to take a picture
-    // @Values: 1:Servo,2:Relay, 3:GoPro in Solo Gimbal, 4:Mount (Siyi), 5:MAVLink, 6:MAVLinkCamV2
+    // @Values: 1:Servo,2:Relay, 3:GoPro in Solo Gimbal, 4:Mount (Siyi), 5:MAVLink, 6:MAVLinkCamV2, 7:Scripting
     // @User: Standard
     AP_GROUPINFO_FLAGS("_TYPE",  1, AP_Camera_Params, type, 0, AP_PARAM_FLAG_ENABLE),
 

libraries/AP_Camera/AP_Camera_Scripting.cpp

@@ -0,0 +1,56 @@
+#include "AP_Camera_Scripting.h"
+
+#if AP_CAMERA_SCRIPTING_ENABLED
+
+extern const AP_HAL::HAL& hal;
+
+// entry point to actually take a picture
+bool AP_Camera_Scripting::trigger_pic()
+{
+    // increment counter to allow backend to notice request
+    _cam_state.take_pic_incr++;
+    return true;
+}
+
+// start or stop video recording.  returns true on success
+// set start_recording = true to start record, false to stop recording
+bool AP_Camera_Scripting::record_video(bool start_recording)
+{
+    _cam_state.recording_video = start_recording;
+    return true;
+}
+
+// set camera zoom step.  returns true on success
+// zoom out = -1, hold = 0, zoom in = 1
+bool AP_Camera_Scripting::set_zoom_step(int8_t zoom_step)
+{
+    _cam_state.zoom_step = zoom_step;
+    return true;
+}
+
+// set focus in, out or hold.  returns true on success
+// focus in = -1, focus hold = 0, focus out = 1
+bool AP_Camera_Scripting::set_manual_focus_step(int8_t focus_step)
+{
+    _cam_state.focus_step = focus_step;
+    _cam_state.auto_focus = false;
+    return true;
+}
+
+// auto focus.  returns true on success
+bool AP_Camera_Scripting::set_auto_focus()
+{
+    _cam_state.auto_focus = true;
+    _cam_state.focus_step = 0;
+    return true;
+}
+
+// access for scripting backend to retrieve state
+// returns true on success and cam_state is filled in
+bool AP_Camera_Scripting::get_state(camera_state_t& cam_state) const
+{
+    cam_state = _cam_state;
+    return true;
+}
+
+#endif // AP_CAMERA_SCRIPTING_ENABLED

libraries/AP_Camera/AP_Camera_Scripting.h

@@ -0,0 +1,62 @@
+/*
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+  Camera driver for scripting backends
+ */
+#pragma once
+
+#include "AP_Camera_Backend.h"
+
+#if AP_CAMERA_SCRIPTING_ENABLED
+
+class AP_Camera_Scripting : public AP_Camera_Backend
+{
+public:
+
+    // Constructor
+    using AP_Camera_Backend::AP_Camera_Backend;
+
+    /* Do not allow copies */
+    CLASS_NO_COPY(AP_Camera_Scripting);
+
+    // entry point to actually take a picture
+    bool trigger_pic() override;
+
+    // start or stop video recording.  returns true on success
+    // set start_recording = true to start record, false to stop recording
+    bool record_video(bool start_recording) override;
+
+    // set camera zoom step.  returns true on success
+    // zoom out = -1, hold = 0, zoom in = 1
+    bool set_zoom_step(int8_t zoom_step) override;
+
+    // set focus in, out or hold.  returns true on success
+    // focus in = -1, focus hold = 0, focus out = 1
+    bool set_manual_focus_step(int8_t focus_step) override;
+
+    // auto focus.  returns true on success
+    bool set_auto_focus() override;
+
+    // returns true on success and cam_state is filled in
+    bool get_state(camera_state_t& cam_state) const override;
+
+private:
+
+    // current state
+    camera_state_t _cam_state;
+};
+
+#endif // AP_CAMERA_SCRIPTING_ENABLED

libraries/AP_Camera/AP_Camera_config.h

@@ -34,3 +34,7 @@
 #ifndef AP_CAMERA_SOLOGIMBAL_ENABLED
 #define AP_CAMERA_SOLOGIMBAL_ENABLED AP_CAMERA_BACKEND_DEFAULT_ENABLED && HAL_SOLO_GIMBAL_ENABLED
 #endif
+
+#ifndef AP_CAMERA_SCRIPTING_ENABLED
+#define AP_CAMERA_SCRIPTING_ENABLED AP_CAMERA_BACKEND_DEFAULT_ENABLED && AP_SCRIPTING_ENABLED
+#endif