Radial Gauges for the Vehicle page.

include/app/pages/vehicle.hpp

@@ -81,11 +81,13 @@ class DataTab : public QWidget {
 
    private:
     Arbiter &arbiter;
-    QWidget *speedo_tach_widget();
+    QWidget *speed_widget();
+    QWidget *rpm_widget();
     // QWidget *mileage_data_widget();
-    QWidget *engine_data_widget();
     QWidget *coolant_temp_widget();
     QWidget *engine_load_widget();
+    QWidget *intake_temp_widget();
+    QWidget *maf_widget();
 
     std::vector<Gauge *> gauges;
 };

include/obd/decoders.hpp

@@ -1,7 +1,75 @@
 #pragma once
-
+#include <limits>
 #include <obd/message.hpp>
 
+namespace {
+
+	inline bool has_obd_data(const Response &resp, int required_bytes)
+	{
+		return resp.success && resp.data.size() >= required_bytes;
+	}
+
+	inline int obd_byte(const Response &resp, int index)
+	{
+		return static_cast<unsigned char>(resp.data.at(index));
+	}
+
+	inline double invalid_obd_value()
+	{
+		return std::numeric_limits<double>::quiet_NaN();
+	}
+
+} // namespace
+
+inline double percentage(const Response &resp)
+{
+	if (!has_obd_data(resp, 1))
+		return invalid_obd_value();
+
+	const int a = obd_byte(resp, 0);
+	return (100.0 / 255.0) * a;
+}
+
+inline double temp(const Response &resp)
+{
+	if (!has_obd_data(resp, 1))
+		return invalid_obd_value();
+
+	const int a = obd_byte(resp, 0);
+	return a - 40.0;
+}
+
+inline double rpm(const Response &resp)
+{
+	if (!has_obd_data(resp, 2))
+		return invalid_obd_value();
+
+	const int a = obd_byte(resp, 0);
+	const int b = obd_byte(resp, 1);
+
+	return ((256.0 * a) + b) / 4.0;
+}
+
+inline double speed(const Response &resp)
+{
+	if (!has_obd_data(resp, 1))
+		return invalid_obd_value();
+
+	return obd_byte(resp, 0);
+}
+
+inline double flow(const Response &resp)
+{
+	if (!has_obd_data(resp, 2))
+		return invalid_obd_value();
+
+	const int a = obd_byte(resp, 0);
+	const int b = obd_byte(resp, 1);
+
+	return ((256.0 * a) + b) / 100.0;
+}
+
+/*
 double percentage(Response resp) { return (100.0 / 255.0) * (int)resp.data.at(0); }
 
 double temp(Response resp) { return (int)resp.data.at(0) - 40; }
@@ -11,4 +79,4 @@ double rpm(Response resp) { return ((256.0 * (int)resp.data.at(0)) + (int)resp.d
 double speed(Response resp) { return (int)resp.data.at(0); }
 
 double flow(Response resp) { return ((256.0 * (int)resp.data.at(0)) + (int)resp.data.at(1)) / 100.0; }
-
+*/

include/obd/message.hpp

@@ -4,6 +4,7 @@
 #include <sstream>
 #include <string>
 #include <QByteArray>
+#include <algorithm>
 
 struct Message {
     unsigned char length;
@@ -27,6 +28,45 @@ struct Request : Message {
     }
 };
 
+struct Response : Message {
+    bool success = false;
+    QByteArray data;
+
+    explicit Response(const QByteArray &payload)
+    : Message{0, 0, 0}
+    {
+        if (payload.size() < 3)
+            return;
+
+        this->length =
+        static_cast<unsigned char>(payload.at(0));
+
+        if (this->length < 2)
+            return;
+
+        this->mode =
+        static_cast<unsigned char>(payload.at(1)) - 0x40;
+
+        this->PID =
+        static_cast<unsigned char>(payload.at(2));
+
+        const int data_length =
+        std::min<int>(this->length - 2, payload.size() - 3);
+
+        if (data_length > 0)
+            this->data = payload.mid(3, data_length);
+
+        this->success = true;
+    }
+
+    Response()
+    : Message{0, 0, 0}
+    , success(false)
+    {
+    }
+};
+
+/*
 struct Response : Message {
     bool success = true;
     QByteArray data;
@@ -42,3 +82,4 @@ struct Response : Message {
 
     Response() { this->success = false; }
 };
+*/