waveformscope: convert buffers to DVL before drawing the waveform

app/widget/scope/waveform/waveform.cpp

@@ -61,11 +61,15 @@ void WaveformScope::initializeGL()
   ManagedDisplayWidget::initializeGL();
 
   makeCurrent();
+
   pipeline_ = OpenGLShader::Create();
   pipeline_->create();
   pipeline_->addShaderFromSourceCode(QOpenGLShader::Vertex, OpenGLShader::CodeDefaultVertex());
   pipeline_->addShaderFromSourceCode(QOpenGLShader::Fragment, Node::ReadFileAsString(":/shaders/rgbwaveform.frag"));
   pipeline_->link();
+
+  framebuffer_.Create(context());
+
   doneCurrent();
 
   connect(context(), &QOpenGLContext::aboutToBeDestroyed, this, &WaveformScope::CleanUp, Qt::DirectConnection);
@@ -75,27 +79,51 @@ void WaveformScope::initializeGL()
 
 void WaveformScope::paintGL()
 {
-  context()->functions()->glClearColor(0, 0, 0, 0);
-  context()->functions()->glClear(GL_COLOR_BUFFER_BIT);
+  QOpenGLFunctions* f = context()->functions();
+
+  f->glClearColor(0, 0, 0, 0);
+  f->glClear(GL_COLOR_BUFFER_BIT);
 
   if (!pipeline_ || !texture_.IsCreated()) {
     return;
   }
 
-  pipeline_->bind();
-  pipeline_->setUniformValue("ove_resolution", texture_.width(), texture_.height());
-  pipeline_->setUniformValue("ove_viewport", width(), height());
+  {
+    // Convert reference frame to display space
+    framebuffer_.Attach(&managed_tex_);
+    framebuffer_.Bind();
 
-  // The general size of a pixel
-  pipeline_->setUniformValue("threshold", 2.0f / static_cast<float>(height()));
+    texture_.Bind();
 
-  pipeline_->release();
+    f->glViewport(0, 0, texture_.width(), texture_.height());
 
-  texture_.Bind();
+    color_service()->ProcessOpenGL();
 
-  OpenGLRenderFunctions::Blit(pipeline_);
+    texture_.Release();
 
-  texture_.Release();
+    framebuffer_.Release();
+    framebuffer_.Detach();
+  }
+
+  {
+    // Draw waveform through shader
+    pipeline_->bind();
+    pipeline_->setUniformValue("ove_resolution", texture_.width(), texture_.height());
+    pipeline_->setUniformValue("ove_viewport", width(), height());
+
+    // The general size of a pixel
+    pipeline_->setUniformValue("threshold", 2.0f / static_cast<float>(height()));
+
+    pipeline_->release();
+
+    f->glViewport(0, 0, width(), height());
+
+    managed_tex_.Bind();
+
+    OpenGLRenderFunctions::Blit(pipeline_);
+
+    managed_tex_.Release();
+  }
 }
 
 void WaveformScope::UploadTextureFromBuffer()
@@ -111,7 +139,10 @@ void WaveformScope::UploadTextureFromBuffer()
       || texture_.height() != buffer_->height()
       || texture_.format() != buffer_->format()) {
     texture_.Destroy();
+    managed_tex_.Destroy();
+
     texture_.Create(context(), buffer_);
+    managed_tex_.Create(context(), buffer_->width(), buffer_->height(), buffer_->format());
   } else {
     texture_.Upload(buffer_);
   }
@@ -127,6 +158,8 @@ void WaveformScope::CleanUp()
 
   pipeline_ = nullptr;
   texture_.Destroy();
+  managed_tex_.Destroy();
+  framebuffer_.Destroy();
 
   doneCurrent();
 }