#include "simpleViewer.h"

using namespace std;

// Draws a spiral
void Viewer::draw() {
  const float nbSteps = 200.0;

  glBegin(GL_QUAD_STRIP);
  for (int i = 0; i < nbSteps; ++i) {
    const float ratio = i / nbSteps;
    const float angle = 21.0 * ratio;
    const float c = cos(angle);
    const float s = sin(angle);
    const float r1 = 1.0 - 0.8f * ratio;
    const float r2 = 0.8f - 0.8f * ratio;
    const float alt = ratio - 0.5f;
    const float nor = 0.5f;
    const float up = sqrt(1.0 - nor * nor);
    glColor3f(1.0 - ratio, 0.2f, ratio);
    glNormal3f(nor * c, up, nor * s);
    glVertex3f(r1 * c, alt, r1 * s);
    glVertex3f(r2 * c, alt + 0.05f, r2 * s);
  }
  glEnd();
}

void Viewer::init() {
  // Restore previous viewer state.
  restoreStateFromFile();

  // Opens help window
  help();
}

QString Viewer::helpString() const {
  QString text("<h2>S i m p l e V i e w e r</h2>");
  text += "Use the mouse to move the camera around the object. ";
  text += "You can respectively revolve around, zoom and translate with the "
          "three mouse buttons. ";
  text += "Left and middle buttons pressed together rotate around the camera "
          "view direction axis<br><br>";
  text += "Pressing <b>Alt</b> and one of the function keys "
          "(<b>F1</b>..<b>F12</b>) defines a camera keyFrame. ";
  text += "Simply press the function key again to restore it. Several "
          "keyFrames define a ";
  text += "camera path. Paths are saved when you quit the application and "
          "restored at next start.<br><br>";
  text +=
      "Press <b>F</b> to display the frame rate, <b>A</b> for the world axis, ";
  text += "<b>Alt+Return</b> for full screen mode and <b>Control+S</b> to save "
          "a snapshot. ";
  text += "See the <b>Keyboard</b> tab in this window for a complete shortcut "
          "list.<br><br>";
  text += "Double clicks automates single click actions: A left button double "
          "click aligns the closer axis with the camera (if close enough). ";
  text += "A middle button double click fits the zoom of the camera and the "
          "right button re-centers the scene.<br><br>";
  text += "A left button double click while holding right button pressed "
          "defines the camera <i>Revolve Around Point</i>. ";
  text += "See the <b>Mouse</b> tab and the documentation web pages for "
          "details.<br><br>";
  text += "Press <b>Escape</b> to exit the viewer.";
  return text;
}
