X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=src%2Fcanvas.cpp;h=dd645a538838f790a1ea61e75ffbe67f3762187b;hb=refs%2Fheads%2Fupstream-master;hp=346890751b80e02fb2b2af22332d43017d1b042f;hpb=97cf902b8751a7709f4f92bc34efd3ef0060104e;p=fstl

diff --git a/src/canvas.cpp b/src/canvas.cpp
index 3468907..dd645a5 100644
--- a/src/canvas.cpp
+++ b/src/canvas.cpp
@@ -1,13 +1,16 @@
 #include <QMouseEvent>
 #include <QDebug>
 
+#include <cmath>
+
 #include "canvas.h"
+#include "backdrop.h"
 #include "glmesh.h"
 #include "mesh.h"
 
 Canvas::Canvas(const QGLFormat& format, QWidget *parent)
     : QGLWidget(format, parent), mesh(NULL),
-      scale(1), tilt(90), yaw(0)
+      scale(1), zoom(1), tilt(90), yaw(0), status(" ")
 {
     // Nothing to do here
 }
@@ -28,28 +31,58 @@ void Canvas::load_mesh(Mesh* m)
                 pow(m->ymax() - m->ymin(), 2) +
                 pow(m->zmax() - m->zmin(), 2));
 
+    // Reset other camera parameters
+    zoom = 1;
+    yaw = 0;
+    tilt = 90;
+
     update();
 
     delete m;
 }
 
+void Canvas::set_status(const QString &s)
+{
+    status = s;
+    update();
+}
+
+void Canvas::clear_status()
+{
+    status = "";
+    update();
+}
+
 void Canvas::initializeGL()
 {
+    initializeGLFunctions();
+
     mesh_shader.addShaderFromSourceFile(QGLShader::Vertex, ":/gl/mesh.vert");
     mesh_shader.addShaderFromSourceFile(QGLShader::Fragment, ":/gl/mesh.frag");
     mesh_shader.link();
 
-    glClearColor(0.0, 0.0, 0.0, 0.0);
-    glEnable(GL_DEPTH_TEST);
+    backdrop = new Backdrop();
 }
 
-void Canvas::paintGL()
+void Canvas::paintEvent(QPaintEvent *event)
 {
+    Q_UNUSED(event);
+
+    glClearColor(0.0, 0.0, 0.0, 0.0);
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    glEnable(GL_DEPTH_TEST);
 
+    backdrop->draw();
     if (mesh)  draw_mesh();
+
+    if (status.isNull())    return;
+
+    QPainter painter(this);
+    painter.setRenderHint(QPainter::Antialiasing);
+    painter.drawText(10, height() - 10, status);
 }
 
+
 void Canvas::draw_mesh()
 {
     mesh_shader.bind();
@@ -62,6 +95,9 @@ void Canvas::draw_mesh()
                 mesh_shader.uniformLocation("view_matrix"),
                 1, GL_FALSE, view_matrix().data());
 
+    // Compensate for z-flattening when zooming
+    glUniform1f(mesh_shader.uniformLocation("zoom"), 1/zoom);
+
     // Find and enable the attribute location for vertex position
     const GLuint vp = mesh_shader.attributeLocation("vertex_position");
     glEnableVertexAttribArray(vp);
@@ -89,18 +125,20 @@ QMatrix4x4 Canvas::view_matrix() const
     QMatrix4x4 m;
     if (width() > height())
     {
-        m.scale(height() / float(width()), 1, 0.5);
+        m.scale(-height() / float(width()), 1, 0.5);
     }
     else
     {
-        m.scale(1, width() / float(height()), 0.5);
+        m.scale(-1, width() / float(height()), 0.5);
     }
+    m.scale(zoom, zoom, 1);
     return m;
 }
 
 void Canvas::mousePressEvent(QMouseEvent* event)
 {
-    if (event->button() == Qt::LeftButton)
+    if (event->button() == Qt::LeftButton ||
+        event->button() == Qt::RightButton)
     {
         mouse_pos = event->pos();
         setCursor(Qt::ClosedHandCursor);
@@ -109,7 +147,8 @@ void Canvas::mousePressEvent(QMouseEvent* event)
 
 void Canvas::mouseReleaseEvent(QMouseEvent* event)
 {
-    if (event->button() == Qt::LeftButton)
+    if (event->button() == Qt::LeftButton ||
+        event->button() == Qt::RightButton)
     {
         unsetCursor();
     }
@@ -117,13 +156,50 @@ void Canvas::mouseReleaseEvent(QMouseEvent* event)
 
 void Canvas::mouseMoveEvent(QMouseEvent* event)
 {
+    auto p = event->pos();
+    auto d = p - mouse_pos;
+
     if (event->buttons() & Qt::LeftButton)
     {
-        auto p = event->pos();
-        auto d = p - mouse_pos;
-        yaw = fmod(yaw + d.x(), 360);
+        yaw = fmod(yaw - d.x(), 360);
         tilt = fmax(0, fmin(180, tilt - d.y()));
-        mouse_pos = p;
         update();
     }
+    else if (event->buttons() & Qt::RightButton)
+    {
+        center = transform_matrix().inverted() *
+                 view_matrix().inverted() *
+                 QVector3D(-d.x() / (0.5*width()),
+                            d.y() / (0.5*height()), 0);
+        update();
+    }
+    mouse_pos = p;
+}
+
+void Canvas::wheelEvent(QWheelEvent *event)
+{
+    // Find GL position before the zoom operation
+    // (to zoom about mouse cursor)
+    auto p = event->pos();
+    QVector3D v(1 - p.x() / (0.5*width()),
+                p.y() / (0.5*height()) - 1, 0);
+    QVector3D a = transform_matrix().inverted() *
+                  view_matrix().inverted() * v;
+
+    if (event->delta() < 0)
+    {
+        for (int i=0; i > event->delta(); --i)
+            zoom *= 1.001;
+    }
+    else if (event->delta() > 0)
+    {
+        for (int i=0; i < event->delta(); ++i)
+            zoom /= 1.001;
+    }
+
+    // Then find the cursor's GL position post-zoom and adjust center.
+    QVector3D b = transform_matrix().inverted() *
+                  view_matrix().inverted() * v;
+    center += b - a;
+    update();
 }