Allow setting of background colour

components/renderers/cpp/include/ftl/render/splat_render.hpp

@@ -45,6 +45,7 @@ class Splatter : public ftl::render::Renderer {
 	bool clipping_;
 	float norm_filter_;
 	bool backcull_;
+	cv::Scalar background_;
 };
 
 }

components/renderers/cpp/src/splat_render.cpp

@@ -6,11 +6,14 @@
 
 #include <opencv2/core/cuda_stream_accessor.hpp>
 
+#include <string>
+
 using ftl::render::Splatter;
 using ftl::rgbd::Channel;
 using ftl::rgbd::Channels;
 using ftl::rgbd::Format;
 using cv::cuda::GpuMat;
+using std::stoul;
 
 static Eigen::Affine3d create_rotation_matrix(float ax, float ay, float az) {
   Eigen::Affine3d rx =
@@ -22,6 +25,22 @@ static Eigen::Affine3d create_rotation_matrix(float ax, float ay, float az) {
   return rz * rx * ry;
 }
 
+static cv::Scalar parseColour(const std::string &colour) {
+	std::string c = colour;
+	if (c[0] == '#') {
+		c.erase(0, 1);
+		unsigned long value = stoul(c.c_str(), nullptr, 16);
+		return cv::Scalar(
+			(value >> 0) & 0xff,
+			(value >> 8) & 0xff,
+			(value >> 16) & 0xff,
+			(value >> 24) & 0xff
+		);
+	}
+
+	return cv::Scalar(0,0,0,0);
+}
+
 Splatter::Splatter(nlohmann::json &config, ftl::rgbd::FrameSet *fs) : ftl::render::Renderer(config), scene_(fs) {
 	if (config["clipping"].is_object()) {
 		auto &c = config["clipping"];
@@ -59,6 +78,11 @@ Splatter::Splatter(nlohmann::json &config, ftl::rgbd::FrameSet *fs) : ftl::rende
 	on("back_cull", [this](const ftl::config::Event &e) {
 		backcull_ = value("back_cull", true);
 	});
+
+	background_ = parseColour(value("background", std::string("#e0e0e0")));
+	on("background", [this](const ftl::config::Event &e) {
+		background_ = parseColour(value("background", std::string("#e0e0e0")));
+	});
 }
 
 Splatter::~Splatter() {
@@ -236,7 +260,7 @@ bool Splatter::render(ftl::rgbd::VirtualSource *src, ftl::rgbd::Frame &out, cuda
 	// Clear all channels to 0 or max depth
 
 	out.get<GpuMat>(Channel::Depth).setTo(cv::Scalar(1000.0f), cvstream);
-	out.get<GpuMat>(Channel::Colour).setTo(cv::Scalar(76,76,76), cvstream);
+	out.get<GpuMat>(Channel::Colour).setTo(background_, cvstream);
 
 	//LOG(INFO) << "Render ready: " << camera.width << "," << camera.height;
 
@@ -310,7 +334,7 @@ bool Splatter::render(ftl::rgbd::VirtualSource *src, ftl::rgbd::Frame &out, cuda
 		params.m_viewMatrixInverse = MatrixConversion::toCUDA(matrix);
 		
 		out.create<GpuMat>(Channel::Right, Format<uchar4>(camera.width, camera.height));
-		out.get<GpuMat>(Channel::Right).setTo(cv::Scalar(76,76,76), cvstream);
+		out.get<GpuMat>(Channel::Right).setTo(background_, cvstream);
 		renderChannel(params, out, Channel::Right, stream);
 	} else if (chan != Channel::None) {
 		if (ftl::rgbd::isFloatChannel(chan)) {
@@ -318,7 +342,7 @@ bool Splatter::render(ftl::rgbd::VirtualSource *src, ftl::rgbd::Frame &out, cuda
 			out.get<GpuMat>(chan).setTo(cv::Scalar(0.0f), cvstream);
 		} else {
 			out.create<GpuMat>(chan, Format<uchar4>(camera.width, camera.height));
-			out.get<GpuMat>(chan).setTo(cv::Scalar(76,76,76,255), cvstream);
+			out.get<GpuMat>(chan).setTo(background_, cvstream);
 		}
 		renderChannel(params, out, chan, stream);
 	}