Allow for multi screen in screen capture

components/codecs/include/ftl/codecs/codecs.hpp

@@ -65,8 +65,16 @@ enum struct definition_t : uint8_t {
 	Invalid
 };
 
+/**
+ * Find exact match definition.
+ */
 definition_t findDefinition(int width, int height);
 
+/**
+ * Find a definition that matches the requested height.
+ */
+definition_t findDefinition(int height);
+
 /**
  * Get width in pixels of definition.
  */

components/codecs/src/bitrates.cpp

@@ -47,3 +47,16 @@ definition_t ftl::codecs::findDefinition(int width, int height) {
 	return definition_t::Invalid;
 }
 
+definition_t ftl::codecs::findDefinition(int height) {
+	int best = 0;
+
+	for(const Resolution res : resolutions) {
+		if (res.height == height) {
+			return static_cast<definition_t>(best);
+		}
+		best++;
+	}
+
+	return definition_t::Invalid;
+}
+

components/rgbd-sources/src/sources/screencapture/screencapture.cpp

@@ -61,8 +61,16 @@ ScreenCapture::ScreenCapture(ftl::rgbd::Source *host)
 	}
 
     s.screen = s.window_attributes.screen;
-	params_.width = s.window_attributes.width;
-	params_.height = s.window_attributes.height;
+	full_width_ = s.window_attributes.width;
+	full_height_ = s.window_attributes.height;
+	offset_x_ = host_->value("offset_x",0);
+	offset_y_ = host_->value("offset_y",0);
+
+	// Choose a correct aspect ratio
+	int awidth = ftl::codecs::getWidth(ftl::codecs::findDefinition(full_height_));
+	params_.width = awidth;
+	params_.height = full_height_;
+
 
     s.ximg = XShmCreateImage(s.display, DefaultVisualOfScreen(s.screen),
 			DefaultDepthOfScreen(s.screen), ZPixmap, NULL, &s.shminfo,
@@ -110,6 +118,13 @@ ScreenCapture::ScreenCapture(ftl::rgbd::Source *host)
 		state_.getLeft() = params_;
 	});
 
+	host_->on("offset_x", [this](const ftl::config::Event &e) {
+		offset_x_ = host_->value("offset_x", 0);
+	});
+
+	host_->on("offset_y", [this](const ftl::config::Event &e) {
+		offset_y_ = host_->value("offset_y", 0);
+	});
 }
 
 ScreenCapture::~ScreenCapture() {
@@ -130,7 +145,7 @@ bool ScreenCapture::compute(int n, int b) {
 	cv::Mat img;
 
 	#ifdef HAVE_X11
-	XShmGetImage(impl_state_->display, impl_state_->root, impl_state_->ximg, 0, 0, 0x00ffffff);
+	XShmGetImage(impl_state_->display, impl_state_->root, impl_state_->ximg, getOffsetX(), getOffsetY(), 0x00ffffff);
     img = cv::Mat(params_.height, params_.width, CV_8UC4, impl_state_->ximg->data);
 	#endif
 

components/rgbd-sources/src/sources/screencapture/screencapture.hpp

@@ -28,12 +28,20 @@ class ScreenCapture : public ftl::rgbd::detail::Source {
 	bool compute(int n=-1, int b=-1);
 	bool isReady();
 
+	int getOffsetX() const { return (offset_x_ > full_width_-params_.width) ? full_width_-params_.width : offset_x_; }
+	int getOffsetY() const { return (offset_y_ > full_height_-params_.height) ? full_height_-params_.height : offset_y_; }
+
 	private:
 	bool ready_;
 	int64_t cap_ts_;
 	int64_t cur_ts_;
 	ftl::rgbd::Frame sframe_;
 
+	int full_width_;
+	int full_height_;
+	int offset_x_;
+	int offset_y_;
+
 	ImplState *impl_state_;
 };