axisglwidget.cpp

// Copyright (c) 2014 Andranik Abrahamyan

#include <QtGui/QtGui>

#include "axisglwidget.h"

AxisGLWidget::AxisGLWidget(QWidget *parent) : QGLWidget(parent) {
  xRot = yRot = zRot = 0;
  black = QColor::fromRgbF(0.0, 0.0, 0.0);
  purple = QColor::fromCmykF(0.39, 0.39, 0.0, 0.0);
}

AxisGLWidget::~AxisGLWidget() {
  makeCurrent();
}

void AxisGLWidget::reset() {
  xRot = yRot = zRot = 0;
}

QSize AxisGLWidget::minimumSizeHint() const {
  return QSize(50, 50);
}

QSize AxisGLWidget::sizeHint() const {
  return QSize(100, 100);
}

void AxisGLWidget::setXRotation(const int angle) {
  xRot = angle;
  emit xRotationChanged(angle);
  updateGL();
}

void AxisGLWidget::setYRotation(const int angle) {
  yRot = angle;
  emit yRotationChanged(angle);
  updateGL();
}

void AxisGLWidget::setZRotation(const int angle) {
  zRot = angle;
  emit zRotationChanged(angle);
  updateGL();
}

void AxisGLWidget::initializeGL() {
  qglClearColor(purple.dark());
	// Enable color tracking
	glEnable(GL_COLOR_MATERIAL);
  // Set Material properties to follow glColor values
	glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
}

void AxisGLWidget::paintGL() {
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  glRotated(xRot / 16.0, 1.0, 0.0, 0.0);
  glRotated(yRot / 16.0, 0.0, 1.0, 0.0);
  glRotated(zRot / 16.0, 0.0, 0.0, 1.0);
  drawAxes();
}

void AxisGLWidget::resizeGL(int width, int height) {
  glViewport(0, 0, width, height);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  // Adjust clipping box
  if (width <= height)
    glOrtho(-10.0f, 10.0f, -10.0f*height/width,
            10.0f*height/width, -10.0f, 10.0f);
  else
    glOrtho(-10.0f*width/height, 10.0f*width/height,
            -10.0f, 10.0f, -10.0f, 10.0f);
  glMatrixMode(GL_MODELVIEW);
}

void AxisGLWidget::drawAxes() {
  glLineWidth(2.0f);
  glScalef(6.0f, 6.0f, 6.0f);
  glBegin(GL_LINES);
  qglColor(QColor::fromRgbF(1, 0, 0));  // X axis is red.
  glVertex3f(0,0,0);
  glVertex3f(1,0,0);
  qglColor(QColor::fromRgbF(0, 1, 0));  // Y axis is green.
  glVertex3f(0,0,0);
  glVertex3f(0,1,0);
  qglColor(QColor::fromRgbF(0, 0, 1));  // Z axis is blue.
  glVertex3f(0,0,0);
  glVertex3f(0,0,1);
  glEnd();
  // Draw labels
  qglColor(QColor::fromRgbF(1, 0, 0));
  renderText(1, 0, 0, "X", QFont("helvetica", 12, QFont::Bold, true));
  qglColor(QColor::fromRgbF(0, 1, 0));
  renderText(0, 1, 0, "Y", QFont("helvetica", 12, QFont::Bold, true));
  qglColor(QColor::fromRgbF(0, 0, 1));
  renderText(0, 0, 1, "Z", QFont("helvetica", 12, QFont::Bold, true));
}