Handle 0 stride vertex data

All examples, even with packed data, set actual vertex size on
the attribute. However, convention is to pass 0 for packed data,
in which case GL will compute vertex size based on number of coordinates
and component data size.

Neither the buffer visitor nor the triangle visitor respected this
convention and relied on the real size to be set. Now computing the
actual stride if it's passed in as 0.

Change-Id: I9a65fd7d8d56f181e31faa93389e3fdd1a973c17
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

2 files changed, 92 insertions, 1 deletions

diff --git a/tests/auto/render/boundingsphere/tst_boundingsphere.cpp b/tests/auto/render/boundingsphere/tst_boundingsphere.cpp
index 767df4604..d5248e865 100644
--- a/tests/auto/render/boundingsphere/tst_boundingsphere.cpp
+++ b/tests/auto/render/boundingsphere/tst_boundingsphere.cpp
@@ -329,6 +329,97 @@ private Q_SLOTS:
         QVERIFY(int(center.y()) == int(expectedCenter.y()));
         QVERIFY(int(center.z()) == int(expectedCenter.z()));
     }
+
+    void checkCustomPackedGeometry()
+    {
+        int drawVertexCount = 6;
+        QVector3D expectedCenter(-0.488892f, 0.0192147f, -75.4804f);
+        float expectedRadius = 25.5442f;
+
+        // two triangles with different Z
+        QByteArray vdata;
+        vdata.resize(6 * 3 * sizeof(float));
+        float *vp = reinterpret_cast<float *>(vdata.data());
+        *vp++ = -1.0f;
+        *vp++ = 1.0f;
+        *vp++ = -100.0f;
+        *vp++ = 0.0f;
+        *vp++ = 0.0f;
+        *vp++ = -100.0f;
+        *vp++ = 1.0f;
+        *vp++ = 1.0f;
+        *vp++ = -100.0f;
+
+        *vp++ = -1.0f;
+        *vp++ = -1.0f;
+        *vp++ = -50.0f;
+        *vp++ = 0.0f;
+        *vp++ = 0.0f;
+        *vp++ = -50.0f;
+        *vp++ = 1.0f;
+        *vp++ = -1.0f;
+        *vp++ = -50.0f;
+
+        QScopedPointer<Qt3DCore::QEntity> entity(new Qt3DCore::QEntity);
+        QScopedPointer<Qt3DRender::TestAspect> test(new Qt3DRender::TestAspect(entity.data()));
+        Qt3DRender::QBuffer *vbuffer = new Qt3DRender::QBuffer;
+
+        vbuffer->setData(vdata);
+        Qt3DRender::Render::Buffer *vbufferBackend = test->nodeManagers()->bufferManager()->getOrCreateResource(vbuffer->id());
+        vbufferBackend->setRenderer(test->renderer());
+        vbufferBackend->setManager(test->nodeManagers()->bufferManager());
+        simulateInitialization(vbuffer, vbufferBackend);
+
+        Qt3DRender::QGeometry *g = new Qt3DRender::QGeometry;
+        g->addAttribute(new Qt3DRender::QAttribute);
+
+        const QVector<Qt3DRender::QAttribute *> attrs = g->attributes();
+        Qt3DRender::QAttribute *attr = attrs[0];
+        attr->setBuffer(vbuffer);
+        attr->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
+        attr->setVertexBaseType(Qt3DRender::QAttribute::Float);
+        attr->setVertexSize(3);
+        attr->setCount(6);
+        attr->setByteOffset(0);
+        attr->setByteStride(0);
+
+        Qt3DRender::QGeometryRenderer *gr = new Qt3DRender::QGeometryRenderer;
+        gr->setVertexCount(drawVertexCount);
+        gr->setGeometry(g);
+        entity->addComponent(gr);
+
+        Qt3DRender::Render::Attribute *attr0Backend = test->nodeManagers()->attributeManager()->getOrCreateResource(attrs[0]->id());
+        attr0Backend->setRenderer(test->renderer());
+        simulateInitialization(attrs[0], attr0Backend);
+
+        Qt3DRender::Render::Geometry *gBackend = test->nodeManagers()->geometryManager()->getOrCreateResource(g->id());
+        gBackend->setRenderer(test->renderer());
+        simulateInitialization(g, gBackend);
+
+        Qt3DRender::Render::GeometryRenderer *grBackend = test->nodeManagers()->geometryRendererManager()->getOrCreateResource(gr->id());
+        grBackend->setRenderer(test->renderer());
+        grBackend->setManager(test->nodeManagers()->geometryRendererManager());
+        simulateInitialization(gr, grBackend);
+
+        Qt3DRender::Render::Entity *entityBackend = test->nodeManagers()->renderNodesManager()->getOrCreateResource(entity->id());
+        entityBackend->setRenderer(test->renderer());
+        simulateInitialization(entity.data(), entityBackend);
+
+        Qt3DRender::Render::CalculateBoundingVolumeJob calcBVolume;
+        calcBVolume.setManagers(test->nodeManagers());
+        calcBVolume.setRoot(test->sceneRoot());
+        calcBVolume.run();
+
+        QVector3D center = entityBackend->localBoundingVolume()->center();
+        float radius = entityBackend->localBoundingVolume()->radius();
+        qDebug() << radius << center;
+
+        // truncate and compare integers only
+        QVERIFY(int(radius) == int(expectedRadius));
+        QVERIFY(int(center.x()) == int(expectedCenter.x()));
+        QVERIFY(int(center.y()) == int(expectedCenter.y()));
+        QVERIFY(int(center.z()) == int(expectedCenter.z()));
+    }
 };
 
 QTEST_MAIN(tst_BoundingSphere)
diff --git a/tests/auto/render/trianglevisitor/tst_trianglevisitor.cpp b/tests/auto/render/trianglevisitor/tst_trianglevisitor.cpp
index 1e76751cc..08d06f0ea 100644
--- a/tests/auto/render/trianglevisitor/tst_trianglevisitor.cpp
+++ b/tests/auto/render/trianglevisitor/tst_trianglevisitor.cpp
@@ -194,7 +194,7 @@ private Q_SLOTS:
         positionAttribute->setDataType(Qt3DRender::QAttribute::Float);
         positionAttribute->setDataSize(3);
         positionAttribute->setCount(6);
-        positionAttribute->setByteStride(3*4);
+        positionAttribute->setByteStride(0);
         positionAttribute->setByteOffset(0);
         positionAttribute->setAttributeType(Qt3DRender::QAttribute::VertexAttribute);
         geometry->addAttribute(positionAttribute.data());