1 files changed, 304 insertions, 0 deletions
diff --git a/src/glwidget.cpp b/src/glwidget.cpp
new file mode 100755
index 0000000..8c92f5b
--- /dev/null
+++ b/src/glwidget.cpp
@@ -0,0 +1,304 @@
+#include "glwidget.h"
+
+#include <QApplication>
+#include <QKeyEvent>
+#include <iostream>
+
+#define SPEED 1.5
+#define ROTATE_SPEED 0.0025
+
+using namespace std;
+using namespace Eigen;
+
+GLWidget::GLWidget(QWidget *parent) :
+    QOpenGLWidget(parent),
+    m_arap(),
+    m_camera(),
+    m_defaultShader(),
+    m_pointShader(),
+    m_vSize(),
+    m_movementScaling(),
+    m_vertexSelectionThreshold(),
+    // Movement
+    m_deltaTimeProvider(),
+    m_intervalTimer(),
+    // Timing
+    m_forward(),
+    m_sideways(),
+    m_vertical(),
+    // Mouse handler stuff
+    m_lastX(),
+    m_lastY(),
+    m_leftCapture(false),
+    m_rightCapture(false),
+    m_rightClickSelectMode(SelectMode::None),
+    m_lastSelectedVertex(-1)
+{
+    // GLWidget needs all mouse move events, not just mouse drag events
+    setMouseTracking(true);
+
+    // Hide the cursor since this is a fullscreen app
+    QApplication::setOverrideCursor(Qt::ArrowCursor);
+
+    // GLWidget needs keyboard focus
+    setFocusPolicy(Qt::StrongFocus);
+
+    // Function tick() will be called once per interva
+    connect(&m_intervalTimer, SIGNAL(timeout()), this, SLOT(tick()));
+}
+
+GLWidget::~GLWidget()
+{
+    if (m_defaultShader != nullptr) delete m_defaultShader;
+    if (m_pointShader   != nullptr) delete m_pointShader;
+}
+
+// ================== Basic OpenGL Overrides
+
+void GLWidget::initializeGL()
+{
+    // Initialize GL extension wrangler
+    glewExperimental = GL_TRUE;
+    GLenum err = glewInit();
+    if (err != GLEW_OK) fprintf(stderr, "Error while initializing GLEW: %s\n", glewGetErrorString(err));
+    fprintf(stdout, "Successfully initialized GLEW %s\n", glewGetString(GLEW_VERSION));
+
+    // Set clear color to white
+    glClearColor(1, 1, 1, 1);
+
+    // Enable depth-testing and backface culling
+    glEnable(GL_DEPTH_TEST);
+    glEnable(GL_CULL_FACE);
+    glCullFace(GL_BACK);
+
+    // Initialize shaders
+    m_defaultShader = new Shader(":resources/shaders/shader.vert",      ":resources/shaders/shader.frag");
+    m_pointShader   = new Shader(":resources/shaders/anchorPoint.vert", ":resources/shaders/anchorPoint.geom", ":resources/shaders/anchorPoint.frag");
+
+    // Initialize ARAP, and get parameters needed to decide the camera position, etc
+    Vector3f coeffMin, coeffMax;
+    m_arap.init(coeffMin, coeffMax);
+
+    Vector3f center = (coeffMax + coeffMin) / 2.0f;
+    float extentLength  = (coeffMax - coeffMin).norm();
+
+    // Screen-space size of vertex points
+    m_vSize = 0.005 * extentLength;
+
+    // Scale all movement by this amount
+    m_movementScaling = extentLength * 0.5;
+
+    // When raycasting, select closest vertex within this distance
+    m_vertexSelectionThreshold = extentLength * 0.025;
+
+    // Note for maintainers: Z-up
+    float fovY = 120;
+    float nearPlane = 0.0001f;
+    float farPlane  = 3 * extentLength;
+
+    // Initialize camera with a reasonable transform
+    Eigen::Vector3f eye    = center - Eigen::Vector3f::UnitZ() * extentLength;
+    Eigen::Vector3f target = center;
+    m_camera.lookAt(eye, target);
+    m_camera.setOrbitPoint(target);
+    m_camera.setPerspective(120, width() / static_cast<float>(height()), nearPlane, farPlane);
+
+    m_deltaTimeProvider.start();
+    m_intervalTimer.start(1000 / 60);
+}
+
+void GLWidget::paintGL()
+{
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+    m_defaultShader->bind();
+    m_defaultShader->setUniform("proj", m_camera.getProjection());
+    m_defaultShader->setUniform("view", m_camera.getView());
+    m_arap.draw(m_defaultShader, GL_TRIANGLES);
+    m_defaultShader->unbind();
+
+    glClear(GL_DEPTH_BUFFER_BIT);
+
+    m_pointShader->bind();
+    m_pointShader->setUniform("proj",   m_camera.getProjection());
+    m_pointShader->setUniform("view",   m_camera.getView());
+    m_pointShader->setUniform("vSize",  m_vSize);
+    m_pointShader->setUniform("width",  width());
+    m_pointShader->setUniform("height", height());
+    m_arap.draw(m_pointShader, GL_POINTS);
+    m_pointShader->unbind();
+}
+
+void GLWidget::resizeGL(int w, int h)
+{
+    glViewport(0, 0, w, h);
+    m_camera.setAspect(static_cast<float>(w) / h);
+}
+
+// ================== Event Listeners
+
+Eigen::Vector3f GLWidget::transformToWorldRay(int x, int y)
+{
+    Eigen::Vector4f clipCoords = Eigen::Vector4f(
+                (float(x) / width()) * 2.f - 1.f,
+                1.f - (float(y) / height()) * 2.f,
+                -1.f,
+                1.f);
+
+    Eigen::Vector4f transformed_coords = m_camera.getProjection().inverse() * clipCoords;
+    transformed_coords = Eigen::Vector4f(transformed_coords.x(), transformed_coords.y(), -1.f, 0.f);
+    transformed_coords = m_camera.getView().inverse() * transformed_coords;
+
+    return Eigen::Vector3f(transformed_coords.x(), transformed_coords.y(), transformed_coords.z()).normalized();
+}
+
+void GLWidget::mousePressEvent(QMouseEvent *event)
+{
+    // Get current mouse coordinates
+    const int currX = event->position().x();
+    const int currY = event->position().y();
+
+    // Get closest vertex to ray
+    const Vector3f ray = transformToWorldRay(currX, currY);
+    const int closest_vertex = m_arap.getClosestVertex(m_camera.getPosition(), ray, m_vertexSelectionThreshold);
+
+    // Switch on button
+    switch (event->button()) {
+    case Qt::MouseButton::RightButton: {
+        // Capture
+        m_rightCapture = true;
+        // Anchor/un-anchor the vertex
+        m_rightClickSelectMode = m_arap.select(m_pointShader, closest_vertex);
+        break;
+    }
+    case Qt::MouseButton::LeftButton: {
+        // Capture
+        m_leftCapture = true;
+        // Select this vertex
+        m_lastSelectedVertex = closest_vertex;
+        break;
+    }
+    default: break;
+    }
+
+    // Set last mouse coordinates
+    m_lastX = currX;
+    m_lastY = currY;
+}
+
+void GLWidget::mouseMoveEvent(QMouseEvent *event)
+{
+    // Return if neither mouse button is currently held down
+    if (!(m_leftCapture || m_rightCapture)) {
+        return;
+    }
+
+    // Get current mouse coordinates
+    const int currX = event->position().x();
+    const int currY = event->position().y();
+
+    // Find ray
+    const Vector3f ray = transformToWorldRay(event->position().x(), event->position().y());
+    Vector3f pos;
+
+    // If right is held down
+    if (m_rightCapture) {
+        // Get closest vertex to ray
+        const int closest_vertex = m_arap.getClosestVertex(m_camera.getPosition(), ray, m_vertexSelectionThreshold);
+
+        // Anchor/un-anchor the vertex
+        if (m_rightClickSelectMode == SelectMode::None) {
+            m_rightClickSelectMode = m_arap.select(m_pointShader, closest_vertex);
+        } else {
+            m_arap.selectWithSpecifiedMode(m_pointShader, closest_vertex, m_rightClickSelectMode);
+        }
+
+        return;
+    }
+
+    // If the selected point is an anchor point
+    if (m_lastSelectedVertex != -1 && m_arap.getAnchorPos(m_lastSelectedVertex, pos, ray, m_camera.getPosition())) {
+        // Move it
+        m_arap.move(m_lastSelectedVertex, pos);
+    } else {
+        // Rotate the camera
+        const int deltaX = currX - m_lastX;
+        const int deltaY = currY - m_lastY;
+        if (deltaX != 0 || deltaY != 0) {
+            m_camera.rotate(deltaY * ROTATE_SPEED, -deltaX * ROTATE_SPEED);
+        }
+    }
+
+    // Set last mouse coordinates
+    m_lastX = currX;
+    m_lastY = currY;
+}
+
+void GLWidget::mouseReleaseEvent(QMouseEvent *event)
+{
+    m_leftCapture = false;
+    m_lastSelectedVertex = -1;
+
+    m_rightCapture = false;
+    m_rightClickSelectMode = SelectMode::None;
+}
+
+void GLWidget::wheelEvent(QWheelEvent *event)
+{
+    float zoom = 1 - event->pixelDelta().y() * 0.1f / 120.f;
+    m_camera.zoom(zoom);
+}
+
+void GLWidget::keyPressEvent(QKeyEvent *event)
+{
+    if (event->isAutoRepeat()) return;
+
+    switch (event->key())
+    {
+    case Qt::Key_W: m_forward  += SPEED; break;
+    case Qt::Key_S: m_forward  -= SPEED; break;
+    case Qt::Key_A: m_sideways -= SPEED; break;
+    case Qt::Key_D: m_sideways += SPEED; break;
+    case Qt::Key_F: m_vertical -= SPEED; break;
+    case Qt::Key_R: m_vertical += SPEED; break;
+    case Qt::Key_C: m_camera.toggleIsOrbiting(); break;
+    case Qt::Key_Equal: m_vSize *= 11.0f / 10.0f; break;
+    case Qt::Key_Minus: m_vSize *= 10.0f / 11.0f; break;
+    case Qt::Key_Escape: QApplication::quit();
+    }
+}
+
+void GLWidget::keyReleaseEvent(QKeyEvent *event)
+{
+    if (event->isAutoRepeat()) return;
+
+    switch (event->key())
+    {
+    case Qt::Key_W: m_forward  -= SPEED; break;
+    case Qt::Key_S: m_forward  += SPEED; break;
+    case Qt::Key_A: m_sideways += SPEED; break;
+    case Qt::Key_D: m_sideways -= SPEED; break;
+    case Qt::Key_F: m_vertical += SPEED; break;
+    case Qt::Key_R: m_vertical -= SPEED; break;
+    }
+}
+
+// ================== Physics Tick
+
+void GLWidget::tick()
+{
+    float deltaSeconds = m_deltaTimeProvider.restart() / 1000.f;
+
+    // Move camera
+    auto look = m_camera.getLook();
+    look.y() = 0;
+    look.normalize();
+    Eigen::Vector3f perp(-look.z(), 0, look.x());
+    Eigen::Vector3f moveVec = m_forward * look.normalized() + m_sideways * perp.normalized() + m_vertical * Eigen::Vector3f::UnitY();
+    moveVec *= m_movementScaling;
+    moveVec *= deltaSeconds;
+    m_camera.move(moveVec);
+
+    // Flag this view for repainting (Qt will call paintGL() soon after)
+    update();
+}