v1.0.0-rc.110 (#16)

This is an UNSTABLE release.

* jfjoch_broker: Add auto-contrast option for preview images
* Frontend: Add logo image
* jfjoch_viewer: Add logo image
* jfjoch_viewer: For image chart allow to set min value to zero
* jfjoch_viewer: For resolution estimation plots, visualization uses 1/d^2 as measure
* jfjoch_viewer: Add 3D unit cell visualization (experimental/WIP/not really there)
* Documentation: Add logo image

Reviewed-on: #16
Co-authored-by: Filip Leonarski <filip.leonarski@psi.ch>
Co-committed-by: Filip Leonarski <filip.leonarski@psi.ch>

viewer/widgets/LatticeVisualizerWidget.cpp

@@ -0,0 +1,150 @@
+// SPDX-FileCopyrightText: 2025 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
+// SPDX-License-Identifier: GPL-3.0-only
+
+#include "LatticeVisualizerWidget.h"
+
+#include <QVBoxLayout>
+#include <QVector3D>
+#include <QQuaternion>
+#include <Qt3DExtras/QCylinderMesh>
+#include <Qt3DRender/QCamera>
+#include <Qt3DExtras/QOrbitCameraController>
+#include <Qt3DRender/QPointLight>
+#include <Qt3DExtras/QForwardRenderer>
+#include <Qt3DRender/QRenderSettings>
+
+LatticeVisualizerWidget::LatticeVisualizerWidget(QWidget *parent) : QWidget(parent) {
+    auto *layout = new QVBoxLayout(this);
+    layout->setContentsMargins(0, 0, 0, 0);
+
+    view = new Qt3DExtras::Qt3DWindow();
+    view->defaultFrameGraph()->setClearColor(Qt::white);
+
+    // Optimize rendering to be on demand (only when scene changes or camera moves)
+    // This prevents the widget from consuming 100% of a CPU core for a static image
+    view->renderSettings()->setRenderPolicy(Qt3DRender::QRenderSettings::OnDemand);
+
+    QWidget *container = QWidget::createWindowContainer(view, this);
+    container->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
+    layout->addWidget(container);
+
+
+    rootEntity = new Qt3DCore::QEntity();
+    view->setRootEntity(rootEntity);
+
+    // Camera setup
+    Qt3DRender::QCamera *camera = view->camera();
+    camera->lens()->setOrthographicProjection(-50.0f, 50.0f, -50.0f, 50.0f, -200.0f, 200.0f);
+    camera->setPosition(QVector3D(0.0f, 0.0f, 50.0f));
+    camera->setViewCenter(QVector3D(0.0f, 0.0f, 0.0f));
+
+    auto *camController = new Qt3DExtras::QOrbitCameraController(rootEntity);
+    camController->setCamera(camera);
+    camController->setLinearSpeed(0.0f); // Disable translation to keep the fixed scale view
+    camController->setLookSpeed(180.0f);
+
+    // Light
+    auto *lightEntity = new Qt3DCore::QEntity(rootEntity);
+    auto *light = new Qt3DRender::QPointLight(lightEntity);
+    light->setColor("white");
+    light->setIntensity(1.0f);
+    lightEntity->addComponent(light);
+
+    // Attach light to camera position or a fixed position?
+    // Attaching to a transform that follows camera is complex without parenting.
+    // For simple viz, a fixed light + a light attached to camera usually works best.
+    // Let's put a simple light at viewer position (approx)
+    auto *lightTransform = new Qt3DCore::QTransform(lightEntity);
+    lightTransform->setTranslation(QVector3D(0.0f, 0.0f, 50.0f));
+    lightEntity->addComponent(lightTransform);
+
+    // Create bars with color-blind friendly palette
+    // Vector a: Vermilion (D55E00)
+    createBar(0, QColor(213, 94, 0));
+    // Vector b: Sky Blue (56B4E9)
+    createBar(1, QColor(86, 180, 233));
+    // Vector c: Bluish Green (009E73)
+    createBar(2, QColor(0, 158, 115));
+}
+
+void LatticeVisualizerWidget::createBar(int index, const QColor &color) {
+    bars[index].entity = new Qt3DCore::QEntity(rootEntity);
+
+    auto *mesh = new Qt3DExtras::QCylinderMesh();
+    mesh->setRadius(1.0f); // Base radius, scaled later
+    mesh->setLength(1.0f); // Base length, scaled later
+    mesh->setRings(20);
+    mesh->setSlices(20);
+
+    bars[index].transform = new Qt3DCore::QTransform();
+
+    bars[index].material = new Qt3DExtras::QPhongMaterial();
+    bars[index].material->setAmbient(color);
+    bars[index].material->setDiffuse(color);
+    bars[index].material->setSpecular(Qt::white);
+    bars[index].material->setShininess(50.0f);
+
+    bars[index].entity->addComponent(mesh);
+    bars[index].entity->addComponent(bars[index].transform);
+    bars[index].entity->addComponent(bars[index].material);
+}
+
+void LatticeVisualizerWidget::updateBar(int index, float x, float y, float z) {
+    QVector3D vec(x, y, z);
+    float length = vec.length();
+
+    if (length < 1e-3f) {
+        bars[index].entity->setEnabled(false);
+        return;
+    }
+    bars[index].entity->setEnabled(true);
+
+    // Cylinder is Y-up by default.
+    QVector3D yAxis(0.0f, 1.0f, 0.0f);
+    QQuaternion rotation = QQuaternion::rotationTo(yAxis, vec.normalized());
+
+    // Center of cylinder is at origin, we need to move it to vec/2
+    QVector3D translation = vec / 2.0f;
+
+    // Scale: X/Z is thickness, Y is length
+    float thickness = 1.0f; // 40 Angstroms thick
+    bars[index].transform->setScale3D(QVector3D(thickness, length, thickness));
+    bars[index].transform->setRotation(rotation);
+    bars[index].transform->setTranslation(translation);
+}
+
+void LatticeVisualizerWidget::setLattice(const float matrix[9]) {
+    // Assuming row-major:
+    // a = (matrix[0], matrix[1], matrix[2])
+    // b = (matrix[3], matrix[4], matrix[5])
+    // c = (matrix[6], matrix[7], matrix[8])
+    updateBar(0, matrix[0], matrix[1], matrix[2]);
+    updateBar(1, matrix[3], matrix[4], matrix[5]);
+    updateBar(2, matrix[6], matrix[7], matrix[8]);
+
+    // Ensure the vertical scale is strictly enforced as requested
+    Qt3DRender::QCamera *camera = view->camera();
+    if (camera) {
+        // Adjust aspect ratio
+        float aspect = (float)width() / (float)height();
+        if (std::isnan(aspect) || height() == 0) aspect = 1.0f;
+
+        // Height is fixed +/- 200
+        float h = 200.0f;
+        float w = h * aspect;
+
+        camera->setTop(h);
+        camera->setBottom(-h);
+        camera->setLeft(-w);
+        camera->setRight(w);
+    }
+}
+
+void LatticeVisualizerWidget::loadImage(std::shared_ptr<const JFJochReaderImage> image) {
+    if (image && image->ImageData().indexing_lattice) {
+        setLattice(image->ImageData().indexing_lattice->GetVector().data());
+    } else {
+        float zero[9] = {0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f};
+        setLattice(zero);
+    }
+}