New "looking Glass" app

Capable of showing a cascade with full bandwidth scan. You can select Min and Max Mhz for the cascade.

You can move a marker so to (aproximately) know  a particular frequency on the cascade. If you press the select button, the app will jump into the RX -> AUDIO app, already tuned into the just "marked" frequency.

This first version SURELY has space for lots of optimizations and improvement in general.

firmware/application/apps/ui_looking_glass_app.hpp

@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
+ * Copyright (C) 2020 euquiq
+ *
+ * This file is part of PortaPack.
+ *
+ * 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 2, 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; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include "ui.hpp"
+#include "portapack.hpp"
+#include "baseband_api.hpp"
+#include "receiver_model.hpp"
+#include "ui_widget.hpp"
+#include "ui_navigation.hpp"
+#include "ui_receiver.hpp"
+#include "string_format.hpp"
+#include "analog_audio_app.hpp"
+#include "spectrum_color_lut.hpp"
+
+namespace ui
+{
+    #define SEARCH_SLICE_WIDTH	20000000 // Each slice bandwidth 20 MHz
+    #define MHZ_DIV	            1000000
+    #define X2_MHZ_DIV	        2000000
+
+    class GlassView : public View
+    {
+    public:
+        GlassView(NavigationView &nav);
+        ~GlassView();
+        std::string title() const override { return "Looking Glass"; };
+
+	    void on_show() override;
+	    void on_hide() override;
+        void focus() override;
+
+    private:
+    	NavigationView& nav_;
+
+        void on_channel_spectrum(const ChannelSpectrum& spectrum);
+        void do_timers();
+        void on_range_changed();
+        void on_lna_changed(int32_t v_db);
+	    void on_vga_changed(int32_t v_db);
+        void add_spectrum_pixel(Color color);
+        void PlotMarker(double pos);
+
+        rf::Frequency f_min { 0 }, f_max { 0 };
+        rf::Frequency search_span { 0 };
+        rf::Frequency f_center { 0 };
+        rf::Frequency f_center_ini { 0 };
+        double marker_pixel_step { 0 };
+        rf::Frequency each_bin_size { SEARCH_SLICE_WIDTH  / 256 };
+        rf::Frequency bins_Hz_size { 0 };
+        uint8_t timing_div { 0 };
+        uint8_t min_color_power { 0 };
+        uint32_t pixel_index { 0 };
+        std::array<Color, 240> spectrum_row = { 0 };
+        ChannelSpectrumFIFO* fifo { nullptr }; 
+
+        Labels labels {
+            { { 0, 0 }, "MIN:     MAX:     LNA   VGA  ", Color::light_grey() },
+            { { 0, 1 * 16 }, "RANGE:     FILTER:       AMP:", Color::light_grey() },
+            { { 0, 2 * 16 }, "MARKER:     MHz +/-    MHz", Color::light_grey() }
+        };
+
+        NumberField field_frequency_min {
+            { 4 * 8, 0 * 16 },
+            4,
+            { 0, 6960 },
+            240,
+            ' '
+        };
+
+        NumberField field_frequency_max {
+            { 13 * 8, 0 * 16 },
+            4,
+            { 240, 7200 },
+            240,
+            ' '
+        };
+
+        LNAGainField field_lna {
+            { 21 * 8, 0 * 16 }
+        };
+        
+        VGAGainField field_vga {
+            { 27 * 8, 0 * 16 }
+        };
+
+        Text text_range {
+  		    { 6 * 8, 1 * 16, 4 * 8, 16 },
+		    ""
+        };
+
+	    OptionsField filter_config {
+            { 18 * 8, 1 * 16 },
+            4,
+            {
+                { "OFF ", 0 },
+                { "MID ", 118 }, //85 +25 (110) + a bit more to kill all blue
+                { "HIGH", 202 }, //168 + 25 (193)
+            }
+	    };
+
+        RFAmpField field_rf_amp {
+            { 29 * 8, 1 * 16 }
+        };
+
+        Text text_marker {
+                { 8 * 8, 2 * 16, 4 * 8, 16 },
+            ""
+        };
+
+        NumberField field_marker {
+            { 7 * 8, 2 * 16 },
+            4,
+            { 0, 6000 },
+            25,
+            ' '
+        };
+
+        Text text_marker_pm {
+                { 20 * 8, 2 * 16, 2 * 8, 16 },
+            ""
+        };
+
+    MessageHandlerRegistration message_handler_spectrum_config {
+		Message::ID::ChannelSpectrumConfig,
+		[this](const Message* const p) {
+			const auto message = *reinterpret_cast<const ChannelSpectrumConfigMessage*>(p);
+			this->fifo = message.fifo;
+		}
+	};
+	MessageHandlerRegistration message_handler_frame_sync {
+		Message::ID::DisplayFrameSync,
+		[this](const Message* const) {
+			if( this->fifo ) {
+				ChannelSpectrum channel_spectrum;
+				while( fifo->out(channel_spectrum) ) {
+					this->on_channel_spectrum(channel_spectrum);
+				}
+			}
+		}
+	};
+
+    };
+}