Merge pull request #587 from Vort/atv_demod_shader_wip

ATV Demod: introducing of new analog TV shader

plugins/channelrx/demodatv/atvdemod.h

@@ -87,7 +87,7 @@ public:
     }
 
 	void setScopeSink(BasebandSampleSink* scopeSink) { m_basebandSink->setScopeSink(scopeSink); }
-    void setTVScreen(TVScreen *tvScreen) { m_basebandSink->setTVScreen(tvScreen); }; //!< set by the GUI
+    void setTVScreen(TVScreenAnalog *tvScreen) { m_basebandSink->setTVScreen(tvScreen); }; //!< set by the GUI
     double getMagSq() const { return m_basebandSink->getMagSq(); } //!< Beware this is scaled to 2^30
     bool getBFOLocked() { return m_basebandSink->getBFOLocked(); }
     void setVideoTabIndex(int videoTabIndex) { m_basebandSink->setVideoTabIndex(videoTabIndex); }

plugins/channelrx/demodatv/atvdemodbaseband.h

@@ -64,7 +64,7 @@ public:
     int getChannelSampleRate() const;
     double getMagSq() const { return m_sink.getMagSq(); }
     void setScopeSink(BasebandSampleSink* scopeSink) { m_sink.setScopeSink(scopeSink); }
-    void setTVScreen(TVScreen *tvScreen) { m_sink.setTVScreen(tvScreen); }
+    void setTVScreen(TVScreenAnalog *tvScreen) { m_sink.setTVScreen(tvScreen); }
     bool getBFOLocked() { return m_sink.getBFOLocked(); }
     void setVideoTabIndex(int videoTabIndex) { m_sink.setVideoTabIndex(videoTabIndex); }
     void setBasebandSampleRate(int sampleRate); //!< To be used when supporting thread is stopped

plugins/channelrx/demodatv/atvdemodgui.cpp

@@ -242,8 +242,6 @@ ATVDemodGUI::ATVDemodGUI(PluginAPI* objPluginAPI, DeviceUISet *deviceUISet, Base
         m_tvSampleRate(48000)
 {
     ui->setupUi(this);
-    ui->screenTV->setColor(false);
-    ui->screenTV->setExtraColumns(true);
     setAttribute(Qt::WA_DeleteOnClose, true);
     connect(this, SIGNAL(widgetRolled(QWidget*,bool)), this, SLOT(onWidgetRolled(QWidget*,bool)));
 

plugins/channelrx/demodatv/atvdemodgui.ui

@@ -1138,7 +1138,7 @@
        <enum>QLayout::SetMinimumSize</enum>
       </property>
       <item>
-       <widget class="TVScreen" name="screenTV" native="true">
+       <widget class="TVScreenAnalog" name="screenTV" native="true">
         <property name="sizePolicy">
          <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
           <horstretch>0</horstretch>
@@ -1242,9 +1242,9 @@
    <container>1</container>
   </customwidget>
   <customwidget>
-   <class>TVScreen</class>
+   <class>TVScreenAnalog</class>
    <extends>QWidget</extends>
-   <header>gui/tvscreen.h</header>
+   <header>gui/tvscreenanalog.h</header>
    <container>1</container>
   </customwidget>
  </customwidgets>

plugins/channelrx/demodatv/atvdemodsink.cpp

@@ -43,14 +43,12 @@ ATVDemodSink::ATVDemodSink() :
     m_ampMin(-1.0f),
     m_ampMax(1.0f),
     m_ampDelta(2.0f),
-    m_colIndex(0),
+    m_sampleOffset(0),
-    m_sampleIndex(0),
+	m_sampleOffsetFrac(0.0f),
-    m_sampleIndexDetected(0),
+    m_sampleOffsetDetected(0),
-    m_hSyncShiftSum(0.0f),
+	m_hSyncShift(0.0f),
-    m_hSyncShiftCount(0),
     m_hSyncErrorCount(0),
     m_amSampleIndex(0),
-    m_rowIndex(0),
     m_lineIndex(0),
     m_ampAverage(4800),
     m_bfoPLL(200/1000000, 100/1000000, 0.01),
@@ -359,7 +357,7 @@ void ATVDemodSink::applyStandard(int sampleRate, const ATVDemodSettings& setting
         // what is left in a line for the image
         m_interleaved        = true;
         m_numberOfVSyncLines = 4;
-        m_numberOfBlackLines = 58;
+        m_numberOfBlackLines = 59;
         m_firstVisibleLine   = 27;
         m_numberSamplesHSyncCrop = (int) (0.085f * lineDuration * sampleRate); // 8.5% of full line empirically
         break;
@@ -486,11 +484,10 @@ void ATVDemodSink::applyChannelSettings(int channelSampleRate, int channelFreque
             m_samplesPerLine - m_numberSamplesPerLineSignals,
             m_settings.m_nbLines - m_numberOfBlackLines
         );
+		m_tvScreenData = m_registeredTVScreen->getData();
     }
 
     m_fieldIndex = 0;
-    m_colIndex = 0;
-    m_rowIndex = 0;
 
     m_channelSampleRate = channelSampleRate;
     m_channelFrequencyOffset = channelFrequencyOffset;
@@ -579,11 +576,10 @@ void ATVDemodSink::applySettings(const ATVDemodSettings& settings, bool force)
                 m_samplesPerLine - m_numberSamplesPerLineSignals,
                 m_settings.m_nbLines - m_numberOfBlackLines
             );
+			m_tvScreenData = m_registeredTVScreen->getData();
         }
 
         m_fieldIndex = 0;
-        m_colIndex = 0;
-        m_rowIndex = 0;
     }
 
     if ((settings.m_topTimeFactor != m_settings.m_topTimeFactor) || force) {

plugins/channelrx/demodatv/atvdemodsink.h

@@ -20,6 +20,7 @@
 
 #include <QElapsedTimer>
 #include <vector>
+#include <memory>
 
 #include "dsp/channelsamplesink.h"
 #include "dsp/basebandsamplesink.h"
@@ -32,7 +33,7 @@
 #include "dsp/phasediscri.h"
 #include "audio/audiofifo.h"
 #include "util/movingaverage.h"
-#include "gui/tvscreen.h"
+#include "gui/tvscreenanalog.h"
 
 #include "atvdemodsettings.h"
 
@@ -44,7 +45,7 @@ public:
     virtual void feed(const SampleVector::const_iterator& begin, const SampleVector::const_iterator& end);
 
   	void setScopeSink(BasebandSampleSink* scopeSink) { m_scopeSink = scopeSink; }
-    void setTVScreen(TVScreen *tvScreen) { m_registeredTVScreen = tvScreen; } //!< set by the GUI
+    void setTVScreen(TVScreenAnalog *tvScreen) { m_registeredTVScreen = tvScreen; } //!< set by the GUI
     double getMagSq() const { return m_magSqAverage; } //!< Beware this is scaled to 2^30
     bool getBFOLocked();
     void setVideoTabIndex(int videoTabIndex) { m_videoTabIndex = videoTabIndex; }
@@ -107,7 +108,8 @@ private:
     SampleVector m_scopeSampleBuffer;
 
     //*************** ATV PARAMETERS  ***************
-    TVScreen *m_registeredTVScreen;
+    TVScreenAnalog *m_registeredTVScreen;
+	std::shared_ptr<TVScreenAnalogData> m_tvScreenData;
 
     //int m_intNumberSamplePerLine;
     int m_numberSamplesPerHTopNom;     //!< number of samples per horizontal synchronization pulse (pulse in ultra-black) - nominal value
@@ -148,15 +150,14 @@ private:
     float m_fltBufferI[6];
     float m_fltBufferQ[6];
 
-    int m_colIndex;
-    int m_sampleIndex;         // assumed (averaged) sample offset from the start of horizontal sync pulse
-    int m_sampleIndexDetected; // detected sample offset from the start of horizontal sync pulse
 	int m_amSampleIndex;
-    int m_rowIndex;
+
+    int m_sampleOffset;         // assumed (averaged) sample offset from the start of horizontal sync pulse
+	float m_sampleOffsetFrac;   // sample offset, fractional part
+    int m_sampleOffsetDetected; // detected sample offset from the start of horizontal sync pulse
     int m_lineIndex;
 
-    float m_hSyncShiftSum;
+	float m_hSyncShift;
-    int m_hSyncShiftCount;
     int m_hSyncErrorCount;
 
     float prevSample;
@@ -198,18 +199,18 @@ private:
     inline void processSample(float& sample, int& sampleVideo)
     {
         // Filling pixel on the current line - reference index 0 at start of sync pulse
-        m_registeredTVScreen->setDataColor(m_sampleIndex - m_numberSamplesPerHSync, sampleVideo, sampleVideo, sampleVideo);
+		m_tvScreenData->setSampleValue(m_sampleOffset - m_numberSamplesPerHSync, sampleVideo);
 
         if (m_settings.m_hSync)
         {
             // Horizontal Synchro detection
             if ((prevSample >= m_settings.m_levelSynchroTop &&
                 sample < m_settings.m_levelSynchroTop) // horizontal synchro detected
-                && (m_sampleIndexDetected > m_samplesPerLine - m_numberSamplesPerHTopNom))
+                && (m_sampleOffsetDetected > m_samplesPerLine - m_numberSamplesPerHTopNom))
             {
-                double sampleIndexDetectedFrac =
+                float sampleOffsetDetectedFrac =
                     (sample - m_settings.m_levelSynchroTop) / (prevSample - sample);
-                double hSyncShift = -m_sampleIndex - sampleIndexDetectedFrac;
+                float hSyncShift = -m_sampleOffset - m_sampleOffsetFrac - sampleOffsetDetectedFrac;
                 if (hSyncShift > m_samplesPerLine / 2)
 					hSyncShift -= m_samplesPerLine;
                 else if (hSyncShift < -m_samplesPerLine / 2)
@@ -218,46 +219,50 @@ private:
                 if (fabs(hSyncShift) > m_numberSamplesPerHTopNom)
                 {
                     m_hSyncErrorCount++;
-                    if (m_hSyncErrorCount >= 8)
+                    if (m_hSyncErrorCount >= 4)
                     {
                         // Fast sync: shift is too large, needs to be fixed ASAP
-                        m_sampleIndex = 0;
+						m_hSyncShift = hSyncShift;
-                        m_hSyncShiftSum = 0.0;
-                        m_hSyncShiftCount = 0;
                         m_hSyncErrorCount = 0;
                     }
                 }
                 else
                 {
-                    m_hSyncShiftSum += hSyncShift;
+					// Slow sync: slight adjustment is needed
-                    m_hSyncShiftCount++;
+					m_hSyncShift = hSyncShift * 0.2f;
                     m_hSyncErrorCount = 0;
                 }
-                m_sampleIndexDetected = 0;
+				m_sampleOffsetDetected = 0;
             }
             else
-                m_sampleIndexDetected++;
+				m_sampleOffsetDetected++;
         }
-        else
+		m_sampleOffset++;
-        {
-            m_hSyncShiftSum = 0.0f;
-            m_hSyncShiftCount = 0;
-        }
-        m_sampleIndex++;
 
         if (m_settings.m_vSync)
         {
-            if (m_sampleIndex > m_fieldDetectStartPos && m_sampleIndex < m_fieldDetectEndPos)
+            if (m_sampleOffset > m_fieldDetectStartPos && m_sampleOffset < m_fieldDetectEndPos)
                 m_fieldDetectSampleCount += sample < m_settings.m_levelSynchroTop;
-            if (m_sampleIndex > m_vSyncDetectStartPos && m_sampleIndex < m_vSyncDetectEndPos)
+            if (m_sampleOffset > m_vSyncDetectStartPos && m_sampleOffset < m_vSyncDetectEndPos)
                 m_vSyncDetectSampleCount += sample < m_settings.m_levelSynchroTop;
         }
 
         // end of line
-        if (m_sampleIndex >= m_samplesPerLine)
+        if (m_sampleOffset >= m_samplesPerLine)
         {
-            m_sampleIndex = 0;
+			if (m_settings.m_hSync)
+			{
+				float sampleOffsetFloat = m_hSyncShift + m_sampleOffsetFrac;
+				m_sampleOffset = sampleOffsetFloat;
+				m_sampleOffsetFrac = sampleOffsetFloat - m_sampleOffset;
+			}
+			else
+			{
+				m_sampleOffset = 0;
+			}
+			m_hSyncShift = 0.0f;
 
+			m_lineIndex++;
 			if (m_settings.m_atvStd == ATVDemodSettings::ATVStdHSkip) {
                 processEOLHSkip();
             } else {
@@ -271,23 +276,9 @@ private:
     // Standard vertical sync
     inline void processEOLClassic()
     {
-        m_lineIndex++;
-
         if (m_lineIndex == m_numberOfVSyncLines + 3 && m_fieldIndex == 0)
         {
-            float shiftSamples = 0.0f;
+			m_registeredTVScreen->renderImage();
-
-            // Slow sync: slight adjustment is needed
-            if (m_hSyncShiftCount != 0 && m_settings.m_hSync)
-            {
-                shiftSamples = m_hSyncShiftSum / m_hSyncShiftCount;
-                m_sampleIndex = shiftSamples;
-                m_hSyncShiftSum = 0.0f;
-                m_hSyncShiftCount = 0;
-                m_hSyncErrorCount = 0;
-            }
-            m_registeredTVScreen->renderImage(0,
-                shiftSamples < -1.0f ? -1.0f : (shiftSamples > 1.0f ? 1.0f : shiftSamples));
         }
 
         if (m_vSyncDetectSampleCount > m_vSyncDetectThreshold &&
@@ -319,38 +310,22 @@ private:
         int rowIndex = m_lineIndex - m_firstVisibleLine;
         if (m_interleaved)
             rowIndex = rowIndex * 2 - m_fieldIndex;
-        m_registeredTVScreen->selectRow(rowIndex);
+
+		m_tvScreenData->selectRow(rowIndex, m_sampleOffsetFrac);
 	}
 
     // Vertical sync is obtained by skipping horizontal sync on the line that triggers vertical sync (new frame)
     inline void processEOLHSkip()
     {
-        m_lineIndex++;
+		if ((m_sampleOffsetDetected > (3 * m_samplesPerLine) / 2) // Vertical sync is first horizontal sync after skip (count at least 1.5 line length)
-        m_rowIndex++;
-
-        if ((m_sampleIndexDetected > (3*m_samplesPerLine) / 2) // Vertical sync is first horizontal sync after skip (count at least 1.5 line length)
             || (!m_settings.m_vSync && (m_lineIndex >= m_settings.m_nbLines))) // Vsync ignored and reached nominal number of lines per frame
         {
-            float shiftSamples = 0.0f;
+			m_registeredTVScreen->renderImage();
-
-            // Slow sync: slight adjustment is needed
-            if (m_hSyncShiftCount != 0 && m_settings.m_hSync)
-            {
-                shiftSamples = m_hSyncShiftSum / m_hSyncShiftCount;
-                m_sampleIndex = shiftSamples;
-                m_hSyncShiftSum = 0.0f;
-                m_hSyncShiftCount = 0;
-                m_hSyncErrorCount = 0;
-            }
-            m_registeredTVScreen->renderImage(0,
-                shiftSamples < -1.0f ? -1.0f : (shiftSamples > 1.0f ? 1.0f : shiftSamples));
 			m_lineIndex = 0;
-            m_rowIndex = 0;
         }
 
-        m_registeredTVScreen->selectRow(m_rowIndex);
+		m_tvScreenData->selectRow(m_lineIndex, m_sampleOffsetFrac);
     }
 };
 
-
 #endif // INCLUDE_ATVDEMODSINK_H

sdrgui/CMakeLists.txt

@@ -51,6 +51,7 @@ set(sdrgui_SOURCES
     gui/transverterbutton.cpp
     gui/transverterdialog.cpp
     gui/tvscreen.cpp
+    gui/tvscreenanalog.cpp
     gui/valuedial.cpp
     gui/valuedialz.cpp
 
@@ -123,6 +124,7 @@ set(sdrgui_HEADERS
     gui/transverterbutton.h
     gui/transverterdialog.h
     gui/tvscreen.h
+    gui/tvscreenanalog.h
     gui/valuedial.h
     gui/valuedialz.h
 

sdrgui/gui/glshadertvarray.cpp

@@ -39,13 +39,11 @@ GLShaderTVArray::GLShaderTVArray(bool blnColor) : m_blnColor(blnColor)
 {
 	m_blnAlphaBlend = false;
     m_blnAlphaReset = false;
-    m_blnExtraColumns = false;
     m_objProgram = 0;
     m_objImage = 0;
     m_objTexture = 0;
     m_intCols = 0;
     m_intRows = 0;
-    m_subsampleShift = 0.0f;
     m_blnInitialized = false;
     m_objCurrentRow = 0;
 
@@ -112,8 +110,7 @@ void GLShaderTVArray::InitializeGL(int intCols, int intRows)
     }
 
     //Image container
-    int cols = intCols + (m_blnExtraColumns ? 2 : 0);
+    m_objImage = new QImage(intCols, intRows, QImage::Format_RGBA8888);
-    m_objImage = new QImage(cols, intRows, QImage::Format_RGBA8888);
     m_objImage->fill(QColor(0, 0, 0));
 
     m_objTexture = new QOpenGLTexture(*m_objImage);
@@ -158,23 +155,11 @@ void GLShaderTVArray::RenderPixels(unsigned char *chrData)
 
     QMatrix4x4 objQMatrix;
 
-    float rectHalfWidth = 1.0f;
-    float sampleSize = 2.0f / m_intCols;
-    if (m_blnExtraColumns)
-        rectHalfWidth += sampleSize;
-    float xShift = sampleSize * m_subsampleShift;
-
     GLfloat arrVertices[] =
     // 2 3
     // 1 4
-    {
+    //1             2            3           3           4            1
-        -rectHalfWidth + xShift, -1.0f, // 1
+    { -1.0f, -1.0f, -1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, -1.0f, -1.0f, -1.0f };
-        -rectHalfWidth + xShift,  1.0f, // 2
-         rectHalfWidth + xShift,  1.0f, // 3
-         rectHalfWidth + xShift,  1.0f, // 3
-         rectHalfWidth + xShift, -1.0f, // 4
-        -rectHalfWidth + xShift, -1.0f  // 1
-    };
 
     GLfloat arrTextureCoords[] =
     // 1 4
@@ -242,8 +227,7 @@ void GLShaderTVArray::RenderPixels(unsigned char *chrData)
 
     m_objTexture->bind();
 
-    ptrF->glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0,
+    ptrF->glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, m_intCols, m_intRows, GL_RGBA,
-        m_intCols + (m_blnExtraColumns ? 2 : 0), m_intRows, GL_RGBA,
             GL_UNSIGNED_BYTE, m_objImage->bits());
 
     ptrF->glEnableVertexAttribArray(0); // vertex
@@ -334,11 +318,9 @@ bool GLShaderTVArray::SetDataColor(int intCol, QRgb objColor)
 
     if (m_blnInitialized)
     {
-        if ((intCol < m_intCols + m_blnExtraColumns) &&
+        if ((intCol < m_intCols) && (intCol >= 0) && (m_objCurrentRow != 0))
-            (intCol >= -m_blnExtraColumns) &&
-            (m_objCurrentRow != 0))
         {
-            m_objCurrentRow[intCol + m_blnExtraColumns] = objColor;
+            m_objCurrentRow[intCol] = objColor;
             blnRslt = true;
         }
     }

sdrgui/gui/glshadertvarray.h

@@ -43,8 +43,6 @@ public:
     GLShaderTVArray(bool blnColor);
     ~GLShaderTVArray();
 
-    void setExtraColumns(bool blnExtraColumns) { m_blnExtraColumns = blnExtraColumns; }
-    void setSubsampleShift(float subsampleShift) { m_subsampleShift = subsampleShift; }
     void setColor(bool blnColor) { m_blnColor = blnColor; }
     void setAlphaBlend(bool blnAlphaBlend) { m_blnAlphaBlend = blnAlphaBlend; }
     void setAlphaReset() { m_blnAlphaReset = true; }
@@ -73,7 +71,6 @@ protected:
 
     int m_intCols;
     int m_intRows;
-    float m_subsampleShift;
 
     QRgb * m_objCurrentRow;
 
@@ -81,7 +78,6 @@ protected:
     bool m_blnColor;
     bool m_blnAlphaBlend;
     bool m_blnAlphaReset;
-    bool m_blnExtraColumns;
 };
 
 #endif /* INCLUDE_GUI_GLTVSHADERARRAY_H_ */

sdrgui/gui/tvscreen.cpp

@@ -37,7 +37,6 @@ TVScreen::TVScreen(bool blnColor, QWidget* parent) :
     m_objTimer.start(40); // capped at 25 FPS
 
     m_chrLastData = NULL;
-    m_subsampleShift = 0.0;
     m_blnConfigChanged = false;
     m_blnDataChanged = false;
     m_blnGLContextInitialized = false;
@@ -59,11 +58,6 @@ void TVScreen::setColor(bool blnColor)
 	m_objGLShaderArray.setColor(blnColor);
 }
 
-void TVScreen::setExtraColumns(bool blnExtraColumns)
-{
-    m_objGLShaderArray.setExtraColumns(blnExtraColumns);
-}
-
 QRgb* TVScreen::getRowBuffer(int intRow)
 {
     if (!m_blnGLContextInitialized)
@@ -74,10 +68,9 @@ QRgb* TVScreen::getRowBuffer(int intRow)
     return m_objGLShaderArray.GetRowBuffer(intRow);
 }
 
-void TVScreen::renderImage(unsigned char * objData, float subsampleShift)
+void TVScreen::renderImage(unsigned char * objData)
 {
     m_chrLastData = objData;
-    m_subsampleShift = subsampleShift;
     m_blnDataChanged = true;
 }
 
@@ -184,7 +177,6 @@ void TVScreen::paintGL()
         m_intAskedRows = 0;
     }
 
-    m_objGLShaderArray.setSubsampleShift(m_subsampleShift);
     m_objGLShaderArray.RenderPixels(m_chrLastData);
 
     m_objMutex.unlock();

sdrgui/gui/tvscreen.h

@@ -46,10 +46,9 @@ public:
     virtual ~TVScreen();
 
     void setColor(bool blnColor);
-    void setExtraColumns(bool blnExtraColumns);
     void resizeTVScreen(int intCols, int intRows);
     void getSize(int& intCols, int& intRows) const;
-    void renderImage(unsigned char * objData, float subsampleShift = 0.0);
+    void renderImage(unsigned char * objData);
     QRgb* getRowBuffer(int intRow);
     void resetImage();
     void resetImage(int alpha);
@@ -74,7 +73,6 @@ private:
     bool m_blnGLContextInitialized;
     int m_intAskedCols;
     int m_intAskedRows;
-    float m_subsampleShift;
 
 
 	// state

sdrgui/gui/tvscreenanalog.cpp

@@ -0,0 +1,249 @@
+///////////////////////////////////////////////////////////////////////////////////
+// Copyright (C) 2020 Vort                                                       //
+// Copyright (C) 2018 F4HKW                                                      //
+// for F4EXB / SDRAngel                                                          //
+//                                                                               //
+// OpenGL interface modernization.                                               //
+//                                                                               //
+// 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 as 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 V3 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/>.          //
+///////////////////////////////////////////////////////////////////////////////////
+
+#include "tvscreenanalog.h"
+
+static const char* vertexShaderSource =
+"attribute highp vec4 vertex;\n"
+"attribute highp vec2 texCoord;\n"
+"varying highp vec2 texCoordVar;\n"
+"void main() {\n"
+"    gl_Position = vertex;\n"
+"    texCoordVar = texCoord;\n"
+"}\n";
+
+static const char* fragmentShaderSource =
+"uniform highp sampler2D tex1;\n"
+"uniform highp sampler2D tex2;\n"
+"uniform highp float imw;\n"
+"uniform highp float imh;\n"
+"uniform highp float tlw;\n"
+"uniform highp float tlh;\n"
+"varying highp vec2 texCoordVar;\n"
+"void main() {\n"
+"    float tlhw = 0.5 * tlw;"
+"    float tlhh = 0.5 * tlh;"
+"    float tys = (texCoordVar.y + tlhh) * imh;\n"
+"    float p1y = floor(tys) * tlh - tlhh;\n"
+"    float p3y = p1y + tlh;\n"
+"    float tshift1 = texture2D(tex2, vec2(0.0, p1y)).r;\n"
+"    float tshift3 = texture2D(tex2, vec2(0.0, p3y)).r;\n"
+"    float shift1 = (1.0 - tshift1 * 2.0) * tlw;\n"
+"    float shift3 = (1.0 - tshift3 * 2.0) * tlw;\n"
+"    float txs1 = (texCoordVar.x + shift1 + tlhw) * imw;\n"
+"    float txs3 = (texCoordVar.x + shift3 + tlhw) * imw;\n"
+"    float p1x = floor(txs1) * tlw - tlhw;\n"
+"    float p3x = floor(txs3) * tlw - tlhw;\n"
+"    float p2x = p1x + tlw;\n"
+"    float p4x = p3x + tlw;\n"
+"    float p1 = texture2D(tex1, vec2(p1x, p1y)).r;\n"
+"    float p2 = texture2D(tex1, vec2(p2x, p1y)).r;\n"
+"    float p3 = texture2D(tex1, vec2(p3x, p3y)).r;\n"
+"    float p4 = texture2D(tex1, vec2(p4x, p3y)).r;\n"
+"    float p12 = mix(p1, p2, fract(txs1));\n"
+"    float p34 = mix(p3, p4, fract(txs3));\n"
+"    float p = mix(p12, p34, fract(tys));\n"
+"    gl_FragColor = vec4(p);\n"
+"}\n";
+
+TVScreenAnalog::TVScreenAnalog(QWidget *parent)
+	: QGLWidget(parent)
+{
+	m_isDataChanged = false;
+	m_data = std::make_shared<TVScreenAnalogData>(5, 1);
+
+	connect(&m_objTimer, SIGNAL(timeout()), this, SLOT(tick()));
+	m_objTimer.start(40); // capped at 25 FPS
+}
+
+void TVScreenAnalog::cleanup()
+{
+	m_shader = nullptr;
+	m_imageTexture = nullptr;
+	m_lineShiftsTexture = nullptr;
+}
+
+std::shared_ptr<TVScreenAnalogData> TVScreenAnalog::getData()
+{
+	return m_data;
+}
+
+void TVScreenAnalog::resizeTVScreen(int intCols, int intRows)
+{
+	qDebug("TVScreen::resizeTVScreen: cols: %d, rows: %d", intCols, intRows);
+
+	int colsAdj = intCols + 4;
+	if (m_data->getWidth() != colsAdj || m_data->getHeight() != intRows)
+		m_data = std::make_shared<TVScreenAnalogData>(colsAdj, intRows);
+}
+
+void TVScreenAnalog::resizeGL(int intWidth, int intHeight)
+{
+	glViewport(0, 0, intWidth, intHeight);
+}
+
+void TVScreenAnalog::initializeGL()
+{
+	initializeOpenGLFunctions();
+
+	connect(QOpenGLContext::currentContext(), &QOpenGLContext::aboutToBeDestroyed,
+		this, &TVScreenAnalog::cleanup); // TODO: when migrating to QOpenGLWidget
+
+	m_shader = std::make_shared<QOpenGLShaderProgram>(this);
+	if (!m_shader->addShaderFromSourceCode(QOpenGLShader::Vertex, vertexShaderSource))
+	{
+		qWarning()
+			<< "TVScreenAnalog::initializeGL: error in vertex shader:"
+			<< m_shader->log();
+		m_shader = nullptr;
+		return;
+	}
+	if (!m_shader->addShaderFromSourceCode(QOpenGLShader::Fragment, fragmentShaderSource))
+	{
+		qWarning()
+			<< "TVScreenAnalog::initializeGL: error in fragment shader:"
+			<< m_shader->log();
+		m_shader = nullptr;
+		return;
+	}
+	if (!m_shader->link())
+	{
+		qWarning()
+			<< "TVScreenAnalog::initializeGL: error linking shader:"
+			<< m_shader->log();
+		m_shader = nullptr;
+		return;
+	}
+
+	m_vertexAttribIndex = m_shader->attributeLocation("vertex");
+	m_texCoordAttribIndex = m_shader->attributeLocation("texCoord");
+	m_textureLoc1 = m_shader->uniformLocation("tex1");
+	m_textureLoc2 = m_shader->uniformLocation("tex2");
+	m_imageWidthLoc = m_shader->uniformLocation("imw");
+	m_imageHeightLoc = m_shader->uniformLocation("imh");
+	m_texelWidthLoc = m_shader->uniformLocation("tlw");
+	m_texelHeightLoc = m_shader->uniformLocation("tlh");
+}
+
+void TVScreenAnalog::initializeTextures()
+{
+	m_imageTexture = std::make_shared<QOpenGLTexture>(QOpenGLTexture::Target2D);
+	m_lineShiftsTexture = std::make_shared<QOpenGLTexture>(QOpenGLTexture::Target2D);
+	m_imageTexture->setSize(m_data->getWidth(), m_data->getHeight());
+	m_lineShiftsTexture->setSize(1, m_data->getHeight());
+	m_imageTexture->setFormat(QOpenGLTexture::RGBA8_UNorm);
+	m_lineShiftsTexture->setFormat(QOpenGLTexture::RGBA8_UNorm);
+	m_imageTexture->setAutoMipMapGenerationEnabled(false);
+	m_lineShiftsTexture->setAutoMipMapGenerationEnabled(false);
+	m_imageTexture->allocateStorage(QOpenGLTexture::RGBA, QOpenGLTexture::UInt8);
+	m_lineShiftsTexture->allocateStorage(QOpenGLTexture::RGBA, QOpenGLTexture::UInt8);
+
+	m_imageTexture->setMinificationFilter(QOpenGLTexture::Nearest);
+	m_imageTexture->setMagnificationFilter(QOpenGLTexture::Nearest);
+	m_lineShiftsTexture->setMinificationFilter(QOpenGLTexture::Nearest);
+	m_lineShiftsTexture->setMagnificationFilter(QOpenGLTexture::Nearest);
+	m_imageTexture->setWrapMode(QOpenGLTexture::DirectionS, QOpenGLTexture::ClampToBorder);
+	m_imageTexture->setWrapMode(QOpenGLTexture::DirectionT, QOpenGLTexture::ClampToEdge);
+	m_lineShiftsTexture->setWrapMode(QOpenGLTexture::DirectionS, QOpenGLTexture::Repeat);
+	m_lineShiftsTexture->setWrapMode(QOpenGLTexture::DirectionT, QOpenGLTexture::ClampToEdge);
+}
+
+void TVScreenAnalog::renderImage()
+{
+	m_isDataChanged = true;
+}
+
+void TVScreenAnalog::tick()
+{
+	if (m_isDataChanged)
+	{
+		update();
+	}
+}
+
+void TVScreenAnalog::paintGL()
+{
+	m_isDataChanged = false;
+
+	if (!m_shader)
+	{
+		glClearColor(0.2f, 0.0f, 0.0f, 1.0f);
+		glClear(GL_COLOR_BUFFER_BIT);
+		return;
+	}
+
+	if (!m_imageTexture ||
+		m_imageTexture->width() != m_data->getWidth() ||
+		m_imageTexture->height() != m_data->getHeight())
+	{
+		initializeTextures();
+	}
+
+	float imageWidth = m_data->getWidth();
+	float imageHeight = m_data->getHeight();
+	float texelWidth = 1.0f / imageWidth;
+	float texelHeight = 1.0f / imageHeight;
+
+	m_shader->bind();
+	m_shader->setUniformValue(m_textureLoc1, 0);
+	m_shader->setUniformValue(m_textureLoc2, 1);
+	m_shader->setUniformValue(m_imageWidthLoc, imageWidth);
+	m_shader->setUniformValue(m_imageHeightLoc, imageHeight);
+	m_shader->setUniformValue(m_texelWidthLoc, texelWidth);
+	m_shader->setUniformValue(m_texelHeightLoc, texelHeight);
+
+	glActiveTexture(GL_TEXTURE0);
+	m_imageTexture->bind();
+	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0,
+		m_data->getWidth(), m_data->getHeight(), GL_RGBA, GL_UNSIGNED_BYTE, m_data->getImageData());
+
+	glActiveTexture(GL_TEXTURE1);
+	m_lineShiftsTexture->bind();
+	glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0,
+		1, m_data->getHeight(), GL_RGBA, GL_UNSIGNED_BYTE, m_data->getLineShiftData());
+
+	float rectHalfWidth = 1.0f + 4.0f / (imageWidth - 4.0f);
+	GLfloat vertices[] =
+	{
+		-rectHalfWidth, -1.0f,
+		-rectHalfWidth,  1.0f,
+		 rectHalfWidth,  1.0f,
+		 rectHalfWidth, -1.0f
+	};
+
+	static const GLfloat arrTextureCoords[] =
+	{
+		0.0f, 1.0f,
+		0.0f, 0.0f,
+		1.0f, 0.0f,
+		1.0f, 1.0f
+	};
+
+	glVertexAttribPointer(m_vertexAttribIndex, 2, GL_FLOAT, GL_FALSE, 0, vertices);
+	glEnableVertexAttribArray(m_vertexAttribIndex);
+	glVertexAttribPointer(m_texCoordAttribIndex, 2, GL_FLOAT, GL_FALSE, 0, arrTextureCoords);
+	glEnableVertexAttribArray(m_texCoordAttribIndex);
+	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+	glDisableVertexAttribArray(m_vertexAttribIndex);
+	glDisableVertexAttribArray(m_texCoordAttribIndex);
+
+	m_shader->release();
+}

sdrgui/gui/tvscreenanalog.h

@@ -0,0 +1,156 @@
+///////////////////////////////////////////////////////////////////////////////////
+// Copyright (C) 2020 Vort                                                       //
+// Copyright (C) 2018 F4HKW                                                      //
+// for F4EXB / SDRAngel                                                          //
+//                                                                               //
+// OpenGL interface modernization.                                               //
+// See: http://doc.qt.io/qt-5/qopenglshaderprogram.html                          //
+//                                                                               //
+// 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 as 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 V3 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/>.          //
+///////////////////////////////////////////////////////////////////////////////////
+
+#ifndef INCLUDE_TVSCREENANALOG_H
+#define INCLUDE_TVSCREENANALOG_H
+
+#include "export.h"
+
+#include <memory>
+#include <algorithm>
+
+#include <QImage>
+#include <QMutex>
+#include <QTimer>
+#include <QGLWidget>
+#include <QOpenGLTexture>
+#include <QOpenGLFunctions>
+#include <QOpenGLShaderProgram>
+
+class TVScreenAnalogData
+{
+public:
+	TVScreenAnalogData(int width, int height)
+	{
+		m_width = width;
+		m_height = height;
+
+		m_imageData = new int[width * height];
+		m_lineShiftData = new int[height];
+		m_outOfBoundsLine = new int[width];
+		m_currentLine = m_outOfBoundsLine;
+
+		std::fill(m_imageData, m_imageData + width * height, 0);
+		std::fill(m_lineShiftData, m_lineShiftData + height, 127);
+	}
+
+	~TVScreenAnalogData()
+	{
+		delete[] m_imageData;
+		delete[] m_lineShiftData;
+		delete[] m_outOfBoundsLine;
+	}
+
+	int getWidth()
+	{
+		return m_width;
+	}
+
+	int getHeight()
+	{
+		return m_height;
+	}
+
+	const int* getImageData()
+	{
+		return m_imageData;
+	}
+
+	const int* getLineShiftData()
+	{
+		return m_lineShiftData;
+	}
+
+	void selectRow(int line, float shift)
+	{
+		if ((line < m_height) && (line >= 0))
+		{
+			m_currentLine = m_imageData + line * m_width;
+			m_lineShiftData[line] = (1.0f + shift) * 127.5f;
+		}
+		else
+		{
+			m_currentLine = m_outOfBoundsLine;
+		}
+	}
+
+	void setSampleValue(int column, int value)
+	{
+		if ((column < m_width - 2) && (column >= -2))
+		{
+			m_currentLine[column + 2] = value;
+		}
+	}
+
+private:
+	int m_width;
+	int m_height;
+
+	int* m_imageData;
+	int* m_lineShiftData;
+
+	int* m_currentLine;
+	int* m_outOfBoundsLine;
+};
+
+class SDRGUI_API TVScreenAnalog : public QGLWidget, protected QOpenGLFunctions
+{
+	Q_OBJECT
+
+	QTimer m_objTimer;
+
+	bool m_isDataChanged;
+
+	int m_textureLoc1;
+	int m_textureLoc2;
+	int m_imageWidthLoc;
+	int m_imageHeightLoc;
+	int m_texelWidthLoc;
+	int m_texelHeightLoc;
+	int m_vertexAttribIndex;
+	int m_texCoordAttribIndex;
+
+	std::shared_ptr<TVScreenAnalogData> m_data;
+
+	std::shared_ptr<QOpenGLShaderProgram> m_shader;
+	std::shared_ptr<QOpenGLTexture> m_imageTexture;
+	std::shared_ptr<QOpenGLTexture> m_lineShiftsTexture;
+
+public:
+	TVScreenAnalog(QWidget *parent);
+
+	std::shared_ptr<TVScreenAnalogData> getData();
+	void resizeTVScreen(int intCols, int intRows);
+	void renderImage();
+
+private:
+	void initializeTextures();
+	void initializeGL() override;
+	void paintGL() override;
+	void resizeGL(int width, int height);
+
+private slots:
+	void cleanup();
+	void tick();
+};
+
+#endif // INCLUDE_TVSCREENANALOG_H