Visualization of complex functions

CHANGELOG

@@ -23,6 +23,13 @@ Unlike previous GLVis releases, this version requires a C++17 compiler.
 - Added non-persistent mode of the server, when the server terminates after all
   visualization windows are closed.
 
+- Added visualization of complex function data originating from
+  '(Par)ComplexGridFunction' class in MFEM. The complex values are represented
+  by their magnitude, phase, real part or imaginary part, which can be switched
+  by 'Q' key. Additionally, the complex function can be animated by an added
+  harmonic phase. To increase or decrease the phase frequency, use ';' or ':',
+  respectively.
+
 - Implemented DOF numbering in 2D scalar mode, pressing the `n` or `N` key cycles
   through: None → Elements → Edges → Vertices → DOFs. Parallel numbering is now by
   default 'local' to each rank; 'global' vs. 'local' numbering can be toggled with

README.md

@@ -154,6 +154,11 @@ Key commands
   - piece-wise constant refined (LOR)
   - L2 element dof collocation (interpolation)
   - L2 element projection (L2 projection)
+- <kbd>Q</kbd> – Cycle between representations of the visualized *complex data*. The options are:
+  - magnitude
+  - phase
+  - real part
+  - imaginary part
 - <kbd>q</kbd> – Exit
 
 ## Advanced
@@ -196,6 +201,7 @@ Key commands
   - `on` (default): recompute both the bounding box and the value range
   - `value`: recompute only the value range
   - `mesh`: recompute only the bounding box
+- <kbd>Alt</kbd> + <kbd>.</kbd> – Start/stop harmonic complex phase animation (speed can be controlled with <kbd>Alt</kbd> + <kbd>0</kbd> / <kbd>Alt</kbd> + <kbd>Enter</kbd>)
 
 ## 2D scalar data
 

lib/aux_vis.cpp

@@ -204,8 +204,8 @@ GLWindow* InitVisualization(const char name[], int x, int y, int w, int h,
    wnd->setOnKeyDown (SDLK_s, KeyS);
    wnd->setOnKeyDown ('S', KeyS);
 
-   wnd->setOnKeyDown (SDLK_q, KeyQPressed);
-   // wnd->setOnKeyDown (SDLK_Q, KeyQPressed);
+   wnd->setOnKeyDown (SDLK_q, KeyqPressed);
+   wnd->setOnKeyDown ('Q', KeyQPressed);
 
    wnd->setOnKeyDown (SDLK_LEFT, KeyLeftPressed);
    wnd->setOnKeyDown (SDLK_RIGHT, KeyRightPressed);
@@ -609,12 +609,28 @@ void RemoveIdleFunc(void (*Func)(void))
 
 
 thread_local double xang = 0., yang = 0.;
+const double xang_step = 0.2; // angle in degrees
 thread_local gl3::GlMatrix srot;
 thread_local double sph_t, sph_u;
 thread_local GLint oldx, oldy, startx, starty;
 
 thread_local int constrained_spinning = 0;
 
+thread_local double phase_rate = 0.;
+thread_local int phase_anim = 0;
+const double phase_step = 0.001;
+
+void CheckMainIdleFunc()
+{
+   if (locscene->spinning || phase_anim)
+   {
+      AddIdleFunc(MainLoop);
+   }
+   if (!locscene->spinning && !phase_anim)
+   {
+      RemoveIdleFunc(MainLoop);
+   }
+}
 
 void MainLoop()
 {
@@ -624,13 +640,19 @@ void MainLoop()
       if (!constrained_spinning)
       {
          locscene->Rotate(xang, yang);
-         SendExposeEvent();
       }
       else
       {
          locscene->PreRotate(xang, 0.0, 0.0, 1.0);
-         SendExposeEvent();
       }
+   }
+   if (phase_anim)
+   {
+      locscene->UpdateComplexPhase(phase_rate);
+   }
+   if (locscene->spinning || phase_anim)
+   {
+      SendExposeEvent();
       std::this_thread::sleep_for(std::chrono::milliseconds{10}); // sleep for 0.01 seconds
    }
    if (locscene->movie)
@@ -674,7 +696,7 @@ inline void ComputeSphereAngles(int &newx, int &newy,
 void LeftButtonDown(GLWindow::MouseEventInfo *event)
 {
    locscene -> spinning = 0;
-   RemoveIdleFunc(MainLoop);
+   CheckMainIdleFunc();
 
    oldx = event->mouse_x;
    oldy = event->mouse_y;
@@ -1334,12 +1356,17 @@ void KeyCtrlP()
 #endif
 }
 
-void KeyQPressed()
+void KeyqPressed()
 {
    wnd->signalQuit();
    visualize = 0;
 }
 
+void KeyQPressed()
+{
+   Window::SwitchSolution();
+}
+
 void ToggleThreads()
 {
    static const char *state[] = { "running", "stopped" };
@@ -1350,7 +1377,7 @@ void ToggleThreads()
    }
 }
 
-void ThreadsPauseFunc(GLenum state)
+void ThreadsPauseFunc(SDL_Keymod state)
 {
    if (state & KMOD_CTRL)
    {
@@ -1386,57 +1413,96 @@ void CheckSpin()
    {
       xang = 0.;
    }
-   if (xang != 0. || yang != 0.)
-   {
-      locscene->spinning = 1;
-      AddIdleFunc(MainLoop);
-   }
-   else
-   {
-      locscene->spinning = 0;
-      RemoveIdleFunc(MainLoop);
-   }
+   locscene->spinning = (xang != 0. || yang != 0.);
+   CheckMainIdleFunc();
    cout << "Spin angle: " << xang << " degrees / frame" << endl;
 }
 
-const double xang_step = 0.2; // angle in degrees
+void CheckPhaseAnim()
+{
+   if (fabs(phase_rate) < phase_step / 2.)
+   {
+      phase_rate = 0.;
+   }
+   phase_anim = (phase_rate != 0.);
+   CheckMainIdleFunc();
+   cout << "Phase rate: " << phase_rate << " period / frame" << endl;
+}
 
-void Key0Pressed()
+void Key0Pressed(SDL_Keymod mod)
 {
-   if (!locscene -> spinning)
+   if (mod & KMOD_ALT)
+   {
+      if (!phase_anim)
+      {
+         phase_rate = 0.;
+      }
+      phase_rate -= phase_step;
+      CheckPhaseAnim();
+   }
+   else
    {
-      xang = 0;
+      if (!locscene -> spinning)
+      {
+         xang = 0;
+      }
+      xang -= xang_step;
+      CheckSpin();
    }
-   xang -= xang_step;
-   CheckSpin();
 }
 
-void KeyDeletePressed()
+void KeyDeletePressed(SDL_Keymod mod)
 {
-   if (locscene -> spinning)
+   if (mod & KMOD_ALT)
    {
-      xang = yang = 0.;
-      locscene -> spinning = 0;
-      RemoveIdleFunc(MainLoop);
-      constrained_spinning = 1;
+      if (phase_anim)
+      {
+         phase_rate = 0.;
+         phase_anim = 0;
+      }
+      else
+      {
+         phase_rate = phase_step;
+         phase_anim = 1;
+      }
    }
    else
    {
-      xang = xang_step;
-      locscene -> spinning = 1;
-      AddIdleFunc(MainLoop);
+      if (locscene -> spinning)
+      {
+         xang = yang = 0.;
+         locscene -> spinning = 0;
+      }
+      else
+      {
+         xang = xang_step;
+         locscene -> spinning = 1;
+      }
       constrained_spinning = 1;
    }
+   CheckMainIdleFunc();
 }
 
-void KeyEnterPressed()
+void KeyEnterPressed(SDL_Keymod mod)
 {
-   if (!locscene -> spinning)
+   if (mod & KMOD_ALT)
    {
-      xang = 0;
+      if (!phase_anim)
+      {
+         phase_rate = 0.;
+      }
+      phase_rate += phase_step;
+      CheckPhaseAnim();
+   }
+   else
+   {
+      if (!locscene -> spinning)
+      {
+         xang = 0;
+      }
+      xang += xang_step;
+      CheckSpin();
    }
-   xang += xang_step;
-   CheckSpin();
 }
 
 void Key7Pressed()
@@ -1515,7 +1581,7 @@ void ShiftView(double dx, double dy)
    locscene->ViewCenterY += dy/scale;
 }
 
-void KeyLeftPressed(GLenum state)
+void KeyLeftPressed(SDL_Keymod state)
 {
    if (state & KMOD_CTRL)
    {
@@ -1528,7 +1594,7 @@ void KeyLeftPressed(GLenum state)
    SendExposeEvent();
 }
 
-void KeyRightPressed(GLenum state)
+void KeyRightPressed(SDL_Keymod state)
 {
    if (state & KMOD_CTRL)
    {
@@ -1541,7 +1607,7 @@ void KeyRightPressed(GLenum state)
    SendExposeEvent();
 }
 
-void KeyUpPressed(GLenum state)
+void KeyUpPressed(SDL_Keymod state)
 {
    if (state & KMOD_CTRL)
    {
@@ -1554,7 +1620,7 @@ void KeyUpPressed(GLenum state)
    SendExposeEvent();
 }
 
-void KeyDownPressed(GLenum state)
+void KeyDownPressed(SDL_Keymod state)
 {
    if (state & KMOD_CTRL)
    {

lib/aux_vis.hpp

@@ -52,6 +52,7 @@ void SetLegacyGLOnly(bool status);
 
 void AddIdleFunc(void (*Func)(void));
 void RemoveIdleFunc(void (*Func)(void));
+void CheckMainIdleFunc();
 
 void LeftButtonDown  (GLWindow::MouseEventInfo *event);
 void LeftButtonLoc   (GLWindow::MouseEventInfo *event);
@@ -67,9 +68,10 @@ void TouchPinch(SDL_MultiGestureEvent & e);
 
 void KeyCtrlP();
 void KeyS();
+void KeyqPressed();
 void KeyQPressed();
 void ToggleThreads();
-void ThreadsPauseFunc(GLenum);
+void ThreadsPauseFunc(SDL_Keymod);
 void ThreadsStop();
 void ThreadsRun();
 
@@ -83,14 +85,14 @@ void Key7Pressed();
 void Key8Pressed();
 void Key9Pressed();
 
-void Key0Pressed();
-void KeyDeletePressed();
-void KeyEnterPressed();
+void Key0Pressed(SDL_Keymod);
+void KeyDeletePressed(SDL_Keymod);
+void KeyEnterPressed(SDL_Keymod);
 
-void KeyLeftPressed(GLenum);
-void KeyRightPressed(GLenum);
-void KeyUpPressed(GLenum);
-void KeyDownPressed(GLenum);
+void KeyLeftPressed(SDL_Keymod);
+void KeyRightPressed(SDL_Keymod);
+void KeyUpPressed(SDL_Keymod);
+void KeyDownPressed(SDL_Keymod);
 void KeyJPressed();
 void KeyMinusPressed();
 void KeyPlusPressed();